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April, 2010

Pipeline Inspection Tutorial with NaviModel3

EIVA POST-PROCESSING SUITE

NaviModel3

Pipeline Inspection Post-processing Tutorial with NaviModel3

EIVA Software of 165 Rev. no. 0, 2010-04-23

Pipeline Inspection Tutorial with NM3 EIVA POST-PROCESSING SUITE

NAVIMODEL3 April 2010

8-10 Teglbækvej DK-8361 Hasselager – Aarhus, Denmark Tel: +45 8628 2011 Fax: +45 8628 2111 e-mail: [email protected] Web: www.eiva.dk

0 First Edition Lars Dall Various 23/04/2010

Revision Description By Checked Approved Date

Key words: Pipeline inspection, Hydrographic Surveying, Post-processing

Classification

Open

Internal

Proprietary

Distribution No of copies

N/A N/A N/A



CONTENTS

1. INTRODUCTION ............................................................................................................... 6

2. PIPELINE INSPECTION POST-PROCESSING WITHIN NAVIMODEL ............................. 8 2.1 General Introduction to NaviModel ................................................................................ 8 2.2 Common Tools ........................................................................................................... 10

2.2.1 The NM3 Menu-items .................................................................................... 10 2.2.1.1 The ‘File’ menu ......................................................................................... 10 2.2.1.2 The View menu ........................................................................................ 13 2.2.1.3 The Tools menu ....................................................................................... 19 2.2.1.4 The Help menu ......................................................................................... 29

2.2.2 The NM3 Toolbars ........................................................................................ 30 2.2.2.1 The ‘NM3 Standard’ toolbar ...................................................................... 30 2.2.2.2 The ‘NM3 Video’ toolbar ........................................................................... 31 2.2.2.3 The ‘NM3 Camera’ toolbar........................................................................ 31 2.2.2.4 The ‘Goto’ toolbar ..................................................................................... 32 2.2.2.5 The ‘Pipe Inspection’ toolbar .................................................................... 32

2.2.3 The NM3 Windows ........................................................................................ 33 2.2.3.1 The DTM window ..................................................................................... 34 2.2.3.2 The Project Tree window .......................................................................... 36 2.2.3.3 The Object Properties window .................................................................. 40 2.2.3.4 The Job List window ................................................................................. 43 2.2.3.5 The Log window ....................................................................................... 43 2.2.3.6 The History window .................................................................................. 44 2.2.3.7 The KP Axis window ................................................................................. 45 2.2.3.8 The View Settings window ........................................................................ 47 2.2.3.9 The Video windows .................................................................................. 51

2.3 Special Functions & Methods ..................................................................................... 53 2.3.1 Model Types and Interpolation Methods........................................................ 54

2.3.1.1 Geometry Types ....................................................................................... 54 2.3.1.1.1 TRN Modelling ......................................................................................................54 2.3.1.1.2 TIN Modelling ........................................................................................................56 2.3.1.1.2.1 Principles of Delaunay Triangulation .................................................. 57 2.3.1.1.2.2 Special TIN Model Functions .............................................................. 58

2.3.1.2 Interpolation Methods ............................................................................... 58 2.3.1.2.1 Interpolated Average .............................................................................................59 2.3.1.2.2 TIN Modelling ........................................................................................................63

2.3.2 Generating the DTM ..................................................................................... 63 2.3.2.1 The Quad Tree Principle .......................................................................... 63 2.3.2.2 Indexing a DTM ........................................................................................ 66



2.3.3 Using Toppings in NaviModel3 ...................................................................... 68 2.3.3.1 Pipe Information ....................................................................................... 69 2.3.3.2 Runlines ................................................................................................... 70 2.3.3.3 Displaylines .............................................................................................. 72 2.3.3.4 Waypoints ................................................................................................ 74 2.3.3.5 Chart Definition Series .............................................................................. 75 2.3.3.6 3DS Information ....................................................................................... 76 2.3.3.7 Track information ...................................................................................... 78 2.3.3.8 Video Information ..................................................................................... 79 2.3.3.9 Event Information ..................................................................................... 79

2.3.4 Cleaning Methods ......................................................................................... 81 2.3.4.1 Structured Cleaning .................................................................................. 82 2.3.4.2 Point Edit 3D Cleaning ............................................................................. 83 2.3.4.3 Flat Seabed Cleaning ............................................................................... 85 2.3.4.4 Plane Cleaning with Polygon .................................................................... 86

2.3.5 Digitization Methods ...................................................................................... 87 2.3.5.1 New Digitized Line .................................................................................... 87

2.3.5.1.1 Editing the Digitized Line ......................................................................................88 2.3.5.1.2 Creating Toppings from a Digitized Line ...............................................................90

2.3.5.2 New Digitized Pipeline .............................................................................. 91 2.3.5.3 New Digitized Coverline ........................................................................... 93 2.3.5.4 New Pipeline (Automatic Placement) ........................................................ 95 2.3.5.5 Recalculate KP for all lines ....................................................................... 96 2.3.5.6 Sort Lines ................................................................................................. 96

2.3.6 Pipe Functions .............................................................................................. 96 2.3.6.1 Pipetracker Functionalities ........................................................................ 97

2.3.6.1.1 Validating/invalidating pipetracker data ................................................................98 2.3.6.2 Generating the Pipe ................................................................................ 100 2.3.6.3 Modifying the Pipe .................................................................................. 103

2.3.6.3.1 Visual control of the Pipe ....................................................................................103 2.3.6.3.2 Recalculate Pipe .................................................................................................106 2.3.6.3.3 Use of Pipe Range ..............................................................................................106 2.3.6.3.4 Set KP range .......................................................................................................108

2.3.6.4 Generating the Side Flags ...................................................................... 109 2.3.6.4.1 Using the Flags ...................................................................................................111 2.3.6.4.2 Digitizing Flags ....................................................................................................113 2.3.6.4.3 Adding user defined Flags ..................................................................................114 2.3.6.4.4 Moving the flags ..................................................................................................116 2.3.6.4.5 Export of Freespan and Burial status..................................................................117 2.3.6.4.6 Pipe Listings ........................................................................................................117

2.3.7 Exporting ..................................................................................................... 119 2.3.7.1 The ‘Export’ functionality ........................................................................ 119

2.3.7.1.1 Exporting Pipe Related Information ....................................................................120 2.3.7.1.2 Generating new template ....................................................................................124 2.3.7.1.3 Generating new Batch ........................................................................................126

2.3.7.2 The ‘Area Export’ functionality ................................................................ 127



2.3.7.3 Special Function for Displayline Export ................................................... 130

3. STEP-BY-STEP TUTORIAL, PIPE INSPECTION IN NAVIMODEL3 ............................. 131 3.1 Preparing NaviModel3 for the Pipe Job .................................................................... 131

3.1.1 Loading and configuring the DTM ............................................................... 132 3.1.2 Loading and configuring the Toppings ........................................................ 134

3.2 The Pipe Object ........................................................................................................ 141 3.2.1 Modification of the pipetracker data ............................................................. 142 3.2.2 Digitizing the pipe object ............................................................................. 145

3.2.2.1 Modifying the digitized pipe .................................................................... 148 3.2.3 Generating the Pipe object .......................................................................... 150 3.2.4 Modifying the Pipe ...................................................................................... 151

3.3 The Sideflags ........................................................................................................... 157 3.3.1 Using the Flags ........................................................................................... 159 3.3.2 Modifying the Flags ..................................................................................... 161 3.3.3 Export of Freespan and Burial status .......................................................... 163 3.3.4 Pipe Listings ............................................................................................... 163

3.4 Exporting from a Pipe Object for further processing .................................................. 165



1. INTRODUCTION

The purpose of the present Pipeline Inspection Post-processing Tutorial is to provide a guide to

how the captioned subject can be performed within the EIVA post-processing suite, with

emphasis on the modelling tool, NaviModel3. Within the Tutorial, the various post-processing

tools are presented and an impression of the work- and dataflow through the EIVA post-

processing suite is thereby provided. Furthermore the Tutorial proposes exact methods and

parameters to be used in connection with a typical Pipeline Inspection processing task when

utilizing the suite.

The Tutorial is divided into two main parts, one where all the pipe related tools within

NaviModel3 is introduced and one that presents specific methods for the pipeline inspection

processing.

The part of the tutorial that introduces feasible methods for a pipeline inspection based post-

processing task is to be regarded a sequential and dedicated manual, in which the description of

the various phases is given in the sequence that an actual post-processing process is most likely

to undertake. The specific editing parameters and post-processing rules supplied in some of these

parts of the tutorial are given as inspiration to the user: they might as such be relevant in

connection with some projects and not applicable in connection with others. The user is

requested to consult the particular requirements of his specific project in order to define precise

and dedicated editing and processing rules.

Further the degree of detail of the various chapters is intended to reflect the particular

requirements of such a typical post-processing task. Note that additional, more general

information on post-processing is available on the Help-features supplied with the various

programs that constitute the EIVA post-processing suite as well as in the „EIVA Training &

Documentation Site‟ that can be accessed directly from the Internet or downloaded from the

Download site.

Figure 1 below gives the scope of the tutorial. The figure depicts the data-flow through the EIVA

software suite with the on-line part in the upper left corner (NaviPac & NaviScan). The off-

line/post-processing section in the lower right part of the figure and in particular the modelling

software is hence the subject of the manual (symbolised with the red line). It should be noted,

that NaviEdit and also to some extent NaviPlot, host a series of pipe inspection related tools (see

the yellow lines). These will only be dealt with if considered relevant in the present context,

where the focus has been given on the tools incorporated in NaviModel3.



Figure 1 Scope of the Manual



2. PIPELINE INSPECTION POST-PROCESSING WITHIN NAVIMODEL

2.1 General Introduction to NaviModel

The NaviModel3 DTM modelling programme is primarily a tool for the generation of and

manipulation with Digital Terrain Models on the basis of either multi-beam or single-beam

bathymetric data. The modelling is founded on either Triangular Regular Network (TRN) or on

Triangular Irregular Network (TIN) algorithms. The TRN geometry type models consist of

equally spaced triangular cells as opposed to the TIN geometry type models, where the triangles

are based on the raw data which will result in an irregular network not suited for multi-beam data

or for single-beam data acquired with relatively large line-spacing.

Figure 2 NaviModel3



In addition, NaviModel3 is equipped with a series of dedicated modules that are intended and

designed for specific tasks. These include:

- Online 3D view. This module facilitates visualisation in an online environment in which

various objects can be shown in real time and superimposed on Digital Terrain Model as

well as on other more static objects

- Catenary module that facilitates a variety of catenary based tools, as well as calculations

and visualisations associated with the TMS & Rigmove module of NaviPac as well as of

various associated Pipe- and Cable-laying activities

- Pipeline inspection Module; the subject of the present tutorial

The following procedures comprise a standard pipeline inspection process. Observe that many of

the initial parts are identical to those conducted in connection with a standard with a standard

bathymetric post-processing task:

Creation of new model-file through input of bathymetric data (survey data in NaviEdit

format (typically either binary XYZ (*.ned - NaviScan) or ASCII XYZ (*.xyz – NaviPac)

data) or theoretical data (in ASCII XYZ)

The geometry type must be selected at this stage – either TRN or TIN. Model generation

for TRN will include specification of desired cell size. On the basis of this, NM3 will

automatically generate the three TRN model types: minimum, maximum and average

Input of secondary files (pipe-tracker data, boundary files, runlines, displaylines, digitized

lines etc)

Cleaning of entire TRN model or relative to a boundary file. The cleaning can be

performed utilizing a series of tools that facilitate either manual, or semi-automatic

cleaning of large data-volumes

Determination of the pipe object, via digitization and/or based on a pipe-tracker observation

set

Determination of sideflags and thereby of pipe-status (buried, exposed, free-spanned etc.)

Export of pipe-related items for further processing and documentation, including profiles

(longitudinal and cross))

Generation and manipulation (smoothing) of contours (and contour fillings)

Typical output from NaviModel3 is consequently:

Pipe-related documents

Longitudinal profiles relative to pipe and runline

Cross profiles relative to pipe and runline

Contour curves (including filled contours), EIVA proprietary as well as AutoCAD formats

based on total DTM or relative to a boundary file

Georeferenced images of DTM (user selectable colour- and light-settings) based on total

DTM or relative to a boundary file



2.2 Common Tools

The majority of the NaviModel3 tools are available from the menu, from icons on the icon-bar or

from menus associated with the various windows as is visualised below in Figure 3. The figure

shows items for a typical Bathymetry based NaviModel3 user interface.

Figure 3 NaviModel3 items

2.2.1 The NM3 Menu-items

The NM3 main menu has four main entries: „File‟, „View‟, „Tools‟ and „Help‟. Observe that,

since many of the operations of NM3 are controlled from the different windows and toolbars, not

all functionalities of the software are supported from the menu.

2.2.1.1 The ‘File’ menu

From the „File‟ menu, it is possible to manage the NM3 project as well as to import the

supported raw files and toppings, either via data exported from NaviEdit or by a series of

dedicated exporters.



Figure 4 The 'File' menu

„New‟ will remove all current data and generate a new NM3 project

„Open Project…‟ will open a standard dialogue that facilitates opening of a previously

saved NM3 project. The project file has the extension „nmp‟ and is an XML-files (see

below) that contains all settings of the project as well as the absolute addresses of the files

loaded onto the project

„Import…‟ facilitates importing of toppings through the Import-dialogue visualised below.

From here it is possible to import a series of different topping-types. It is also possible to

define, within the different topping-type, a named import template. The example below

shows an event collection imported with the template „ASAS_Visualsoft‟. Note that it is

possible to drag-and-drop an entire folder onto to dialogue window. NM3 will import all

files that fulfil the criteria defined (including those in subfolders)



„Drop/Merge Multiple Files…‟ will open the dialogue visualised below left. This import is

associated with the importing of supported bathymetric data (*.ned, *.sdb, *.xyz, *.all etc).

Observe that the files/folders must be dragged-and-dropped onto the dialogue. Once this

has been accomplished, a list of all files contained in the folders (including subfolders), will

appear in the column to the left. It is now possible to enter a filter-value to file-extensions

to be accepted by NM3, by pressing the „Filter‟ button and entering the desired extension

(see below right). It is also possible to merge the output into one file (by ticking the „Merge

files‟ option to „On‟)



„Connect to NaviEdit‟ will connect NM3 to the present NaviEdit database and facilitate

loading of edited bathymetric data (*.sdb, *.xyz, *.all etc). Note that the facility only works

if the SQL-server is running (either locally or on the network). Once the connection is

established, a new entry, „NaviEdit‟, will appear at the bottom of the tree structure of the

„Project Tree‟ window as depicted below. By right-clicking on the folder that contains the

data that should be added to the present DTM, the menu shown below right will appear.

Choose the „Add to Survey‟ option and all data in that particular folder will be added to the

present DTM. In case there is no DTM already present in the project, a new will be

generated

„Save Project‟ will save the NM3 project under the present name

„Save Project as‟ will open a dialogue that facilitates renaming the NM3 project

„Auto Save Project…‟ will open the dialogue shown below. Here it is possible to define

properties for the auto save of the present project

2.2.1.2 The View menu

From the „View‟ menu, it is possible to open the variety of windows that the user interface of

NM3 consists of. The functionality of these windows will be described in detail in 2.2.3, The

NM3 Windows, below.



Figure 5 The 'View' menu

„Project Tree‟ will open the „Project Tree‟ window, visualised below. This window will

show the contents of the present NM3-project, divided into different entries, such as

„Surveys‟, „Toppings‟, „Palettes‟, „Colormodes‟ etc

„Object Properties‟ will open the „Properties‟ window that is depicted below. The window

shows the properties and facilitates alteration of the properties of items presently chosen in

the „Project Tree‟ window. The contents of the window is consequently depending on the

nature of the item chosen



„Job List‟ will open the „Job List‟ window shown below. This window shows the

background processes currently being conducted by NM3. Below left is shown the window

while importing, whereas the right window shows how it is possible to stop a job by right-

clicking on it and choosing the „Stop‟ option

„Log Window‟ will open the „Log Window‟ as shown below. The window visualises a

history of all actions being performed by NM3



„History‟ will open the history window that contains a list of all actions being performed by

NM3 that can be undone/deleted (see below). Pressing the arrow-left will undo last action,

whereas pressing arrow-right will redo last action (if applicable)

„KP Axis‟ opens the „KP Axis‟ window as shown below. The window visualises different

KP-based items, such as: runline, pipe information, event information current cursor

position and current DTM position

„Settings‟ will open the „View Settings Window‟ that is shown below. The window

visualises and facilitates alteration of the view settings of NM3. The different settings are

divided into headlines/items such as „Depth Contours‟, „DTM (Surface)‟, „Environment‟,

„Light‟ and „Raw Points‟



„Video‟ will open the menu shown below

By selection it is consequently possible to open all windows (including the event window) at

once or to open the four windows one-by-one. Examples of the three video windows as well

as the event window are located below



„Light setup‟ will open the window below from which it is possible to define light setting

by changing the parameters for light-associated items like „Azimuth‟, „Height‟, „Shininess‟

and brightness. Additionally it is possible to choose some predefined settings, such as

„Shine‟, „High Contrast‟ and „Flat Surface‟ by pressing the associated button

„Reset Window Positions‟ will open the information window shown below´. Choosing the

option „Yes‟ will reset the position of the windows to the default values, once NM3 is

restarted



2.2.1.3 The Tools menu

The tools menu host a series of different functions

Figure 6 NM3 Tools Menu items

„Point Cleaning‟ will open the menu shown below

o „Point Edit 3D‟ will visualise a north/south oriented square geographical selection

tool in the DTM-window (see below). The white square can be resized by

simultaneously pressing CTRL and rolling the mouse wheel

Once the selection is acceptable and the user presses the left mouse-button, the

EIVA PointEdit tool will open (see below). The tool facilitates manual 3D-editing



of large quantities of data. Details of this tool and indeed of the other NM3 cleaning

tools are found in chapter 2.3.4, Cleaning Methods.

o „Flat Seabed Cleaning‟ will visualise a selection tool in the DTM-window identical

to what is used in connection with the „Point Edit 3D‟ described above. Upon

selection, the window below will appear, prompting the user to define whether or

not to delete the points marked for deletion. The points have been defined

automatically by NM3 based on a plane through the corners of the plane and a

vertical distance to this plane

o „Plane cleaning (pick polygon)‟ will invoke a tool that is similar to the „Flat Seabed

Cleaning‟, however the plane is generated on the basis of a user-defined polygon.

Each corner of this polygon is defined by a simple mouse-click on the DTM. Once

the polygon is defined, a deletion/selection tool is opened as shown below. This

shows, in the X-axis, the distance to the plane and in the Y-axis direction, the

distribution of points. As a guide, NM3 will give proposed max and minimum

values (red vertical lines, below left). These can be moved forth and back and the

consequence can be monitored on the DTM (see the red dots, below right)



o „Edit Plugins…‟ will open the text-file shown below. The text in the file describes

how it is possible to execute dedicated cleaning tools in NM3. A tool is an

executable file that reads a point file (from NM3) and writes back the (edited) result

to the same file and consequently back to NM3

„Geodesy Calculator‟ will open the window shown below. The tool facilitates conversion

between geographical coordinates ands grid coordinates in the datum/projection defined

(see below)

„Setup Geodesy‟ facilitates definition of projection and ellipsoid (datum) for the present

project in the dialogue shown below. The parameters are used for instance in connection

with import of *.all files, where the geographical information is given in



latitudes/longitudes, whereas the NM3 is using grid-coordinates. The required conversion is

consequently using the geodesy parameters defined here

„Measure‟ will enable the „Measure‟ tool visualised below. By clicking on the DTM

window, NM3 will accumulate and visualise the distance as visualised

„Ned Monitor…‟ will open the „EIVA NedMonitor‟ window as visualised below. Initially

the monitoring folder must be defined (by clicking on „Options‟)



The action will open a text file („nedmonitor.ini‟ stored in the NaviModel3 bin-directory)

that contains configuration details, such as folder to monitor, required cell size, items to

export etc, for the NedMonitor tool (see above). Once the settings are as desired, save the

file back to its original location. When minimized the NedMonitor icon will dock among

the other icons in the taskbar (see below), however it will constantly be monitoring whether

or not ned-files are being updated/generated in the monitoring folder. If this is the case, the

tool will automatically generate a georeferenced bitmap as well as gridded ASCII xyz-file

for each of the new or updated ned-files, provided both options have been selected in the

configuration settings.



Above the monitoring tool is shown with an empty queue (left) and with a file in the queue

(right). Further it is possible to monitor the actions being performed by the tool: press the

„Log‟ button and the window below will appear, showing actions since NedMonitor was

last started

„Project Settings…‟ will open the ´Project Settings‟ dialogue shown below. In here, it is

possible to define various settings associated with the project, such as „Pipe Settings‟, „Pipe

tracker‟ settings, „Flag Settings‟ and „Export Settings‟.

The „Pipe Settings‟ tab as shown below in Figure 7, hosts a series of settings associated

with the pipe object.

Figure 7 „Pipe Settings‟ tab

„Runline alignment‟ can be used to specify how far below the DTM, the pipe is to be

placed when no other data than the runline exist for the pipe. This is associated with the

priority-list used when generating a pipe object: 1) digitized pipeline 2) pipetracker data

(Kalman line) 3) runline. Consequently: only when no digitized line and no pipe tracker

data is available, will the runline be used to place the pipe

„Acceptable distance to pipetracker‟ is used to define the maximum allowable distance

from a pipe-object to the pipetracker information

„Pipe Diameter‟ specifies the diameter to use when generating the pipe object



„Pipe ModelType‟ specifies the model type to be used when generating a pipe. The user

can overrule this, however a warning will be given when doing so

„Use Pipefilter‟ will define whether or not the Kalman line is to be used to generate the

pipe object

The „Pipe Tracker‟ tab that is shown below in Figure 8, hosts a series of settings associated

with potential Pipe Tracker data.

Figure 8 'Pipe Tracker' tab

„Pipe Filter Flexibility‟ is used to specify the flexibility of the pipe. The figure

expresses how many percent the pipe should be capable of bending (cm per meter)

„Pipe Fixes Quality‟ can be used to define the quality of the pipe fixes. The quality is

expressed as a mean square error (with unit cm)

„Pipe Tracker Quality‟ is used to define the quality of the pipetracker data. The quality

is expressed as a mean square error (with unit cm)

„Pipe Tracker Diameter‟ will express the diameter of the pipe associated with the

pipetracker information (will be visualised in the profile window)

The „Flag Settings‟ tab shown below in Figure 9, hosts a series of settings associated with

the definition and the visualisation of the pipe associated sideflags.



Figure 9 'Flag Settings' tab

„DeltaKp‟ is used to define the distance between the flags (unit: kilometres)

„Left Seabed Inner Distance‟ and „Right Seabed Inner Distance‟ define the distance of

the flags placed to the left and to the right of the pipe respectively, relative to the pipe

diameter

„Left Seabed Outer Distance‟ and „Right Seabed Outer Distance‟ define the absolute

distance, in meters, of the flags placed to the left and to the right of the pipe

respectively

„Maximum Flag Distance‟ specifies the maximum allowable distance between flags

along the pipeline. Used to avoid flag settings on (potential) neighbouring pipes

„Flag Settings Colors‟ can be used to define the colors of the five sideflags when

visualised in the DTM window

„Flag Settings Model Type‟ is used to define the various model types for cover, left and

right seabed inner and outer, respectively

The „Export Settings‟ tab given below in Figure 10, hosts a series of settings associated

with exporting of data for further processing.



Figure 10 'Export Settings' tab

„Default Export Name‟ is used to define the file name for exporting

„Profile Points‟ defines the number of points in an exported cross profile

„Raw Point Gather Width‟ is used to define the search window (height and width) to

look for data for exporting

„Remove Profile is Point Number is below‟ is used to specify the minimum acceptable

number of points in a profile used for export

„Thickness of Raw Profile‟ defines the distance (along the track) the raw cross profile

should gather raw points from

„Width of Profile‟ specifies the total width (in cm) of the cross profile when exporting

„Export Header‟ defines a series of information types used to generate header

information for the exporting functionalities

In connection with bathymetric processing, the main settings of concern are the ones that

can be defined in the „Misc Settings‟ tab, as shown below in Figure 11 in the „Export path‟

and „Toppings path‟ items.



Figure 11 'Misc Settings' tab

In connection with pipeline inspection tasks, the main points of interest are however:

„Cover Auto Distance‟ specifies the cover (in meters) when digitizing a covered pipe

„Get Z From‟ is used to define where the z-component should originate from when

digitizing a pipeline (options are: line z (seabed at digitized point), interpolate Z and

pipetracker Z (use pipetracker z-value and combine with digitized horizontal values)

„Overwrite Burial Status‟ is used to specify whether or not to overwrite burial status

(originating from pipetracker information) when digitizing a pipeline

„Options…‟ will open the ´Options‟ dialogue shown below. The dialogue facilitates

definition of „General‟ items as well as of „Light Settings‟ associated items

Figure 12 Options Dialogue



„DTM creation path‟ specifies the absolute default path for the generation of DTMs.

When clicking on the path a browse-button will appear

„Start NaviModel Maximized‟ can be used to define whether or not NM3 should start in

a maximised window when opening the program

„Startup Model Type‟. For a pipeline inspection task, the normal model type is

„Minimized‟ whereas it is „Average‟ or „Interpolated Average‟ for a bathymetric task.

The default model type can be specified with this setting

„Text Editor‟. The path and file name of the default text editor, to be used when sending

various topping information to a text editor, can be defined with this setting

2.2.1.4 The Help menu

The Help menu hosts two entries.

Figure 13 NM3 Help Menu items

„Graphics‟ will open the window below, in which the evaluation result of the graphics

driver of the computer is shown relative to the recommended (minimum) settings for NM3

„About‟ opens the window below, in which information about present NM3 version as well

as of software protection dongle status is displayed



2.2.2 The NM3 Toolbars

There are five different toolbars in NaviModel3 (see Figure 14):

„NM3 Standard‟ toolbar (see Figure 15)

„NM3 Video‟ toolbar (see Figure 16)

„NM3 Camera‟ toolbar (see Figure 17)

„Goto‟ toolbar (see Figure 18)

„Pipe Inspection‟ toolbar (see Figure 19)

Figure 14 The NM3 Toolbars

2.2.2.1 The ‘NM3 Standard’ toolbar

Figure 15 The NM3 Toolbar items

The NM3 Standard toolbar is comprised by a number of icons/features:

„New Project‟, „Open Project‟ and „Save Project‟ together facilitate standard project-related

actions



„Open Remote Project‟ facilitates a link to the Scene Server, and potentially to (NaviPac or

AIS based) projects that are being executed in remote locations, on the network or on the

Internet

„Toggle 2D/3D‟ will force the DTM window to toggle between 2D and a 3D based

perspective views

„Align View, North Up‟ will force the DTM window to show with (grid) north up

„Light Setting‟ will open the „Light setup‟ dialogue (see chapter 2.2.1.2 above for details)

„Select Palette‟ will open the „Pick palette‟ dialogue

„Toggle Raw Points on/off‟ will toggle the visualisation of raw points on and off (when the

„DrawRawPoints‟ option have been set to „True‟)

„Measure‟ will enable the measurement tool

„Bring Video Here‟ will scroll the video to the present view of the DTM

„Fly Mode‟ facilitates camera movements (of the DTM window) relative to a selectable

runline or pipe-related lines (pipe, flaglines, pipetracker or digitized line). The speed of the

movement can be altered by pressing the + and –buttons next to the icon. Press the „Esc‟

button (when the DTM window is active) to exit the mode

2.2.2.2 The ‘NM3 Video’ toolbar

Figure 16 NM3 Video Toolbar items

The NM3 Video toolbar is constituted by three icons/features (see Figure 16 above), that will

enable scrolling of the video forward and backward as well as to play the present project video.

2.2.2.3 The ‘NM3 Camera’ toolbar

Figure 17 NM3 Camera Toolbar item

The NM3 camera toolbar has only one item (Figure 17), that will enable adding a camera

position of the present view. This can subsequently be used to automatically move from place to

place within the model.



2.2.2.4 The ‘Goto’ toolbar

Figure 18 NM3 GoTo Toolbar items

The NM3 GoTo toolbar is constituted by a four icons/features (see Figure 18 above), that

facilitate moving/stepping forward and backward in the DTM, relative to KP-values of a runline.

2.2.2.5 The ‘Pipe Inspection’ toolbar

Figure 19 NM3 Pipe Inspection Toolbar items

The NM3 GoTo toolbar contains three icons/features (see Figure 19 above), that will enable

digitizing of a pipe (with or without cover) as well as generating a pipe-item relative to pipe

information available in the NM3-project. These functionalities can also be accessed from the

„Project Tree‟ window, by right-clicking on the „Digitized Lines‟ entry and choosing the

appropriate menu-item.



2.2.3 The NM3 Windows

Figure 20 NaviModel3 at start-up

When NaviModel3 is first started from the windows start menu, it looks as shown above in Figure

20. By default, the „Project Tree‟ and „Object Properties‟ windows are opened on the left and the

Log window is opened at the bottom. Each object in the project tree has its own set of properties,

with contents depending on the type of the object. From the „View‟ menu, it is possible to open

additional windows, such as:

The Job List window

The Log window

The History window

The KP Axis window

The View Settings window

The (three) Video windows – including the Event window

It is furthermore possible to reset all windows positions, by choosing menu-item „View – Reset

Window Positions‟. The windows can float freely inside NaviModel3. They can be docked to the



edges of the windows, or they can float onto a secondary screen if one is present. The window

setup is stored as an XML-based configuration file in the NaviModel3 bin folder (layout.config),

so all settings are consequently remembered and used the next time NaviModel3 is started.

The windows that must typically be opened for a bathymetry based NaviModel3 job could look

as visualised below in Figure 21).

Figure 21 NaviModel3 windows for a bathymetry post processing task

2.2.3.1 The DTM window

Irrespective of which NaviModel3 application is being executed, the information visualised in

the DTM window must be regarded an indispensible part of the process. A DTM window for a

typical pipeline inspection based post-processing task is visualised below in Figure 22. Observe

that the majority of the items shown on the figure are described in detail in chapter 2.2.3.8, The

View Settings window, below.

In the figure, the principal item is the colorcoded terrain model, the DTM. In addition and in

support of the pipeline inspection task, a series of entries have been visualised:

The Pipe object as well as associated sideflags and cover flags

The Contour Curves (in the present context with an interval of 0.25 m)

The Live Contours (also with an interval of 0.25 m)

The Legend that, in the present context, shows the information about runlines and tracks

loaded

The DTM palette



The Raw Points, that are visualised relative to the depth

The Statistical Information associated with the Raw Points item

The North Arrow that shows the orientation of the DTM, relative to grid north

The axis of the Target Position (the camera position), including the length of the axis-

arrows

The information related to the Target Position (the information includes date/time, KP,

Easting, Northing and depth)

The Profile Grid visualised around the Target Position

Other items that might be visualised in connection with a bathymetric post-processing task could

be:

Display line(s), defining boundaries of an area

Information from AutoCAD file(s)

Additional DTMs/Surveys

Runline(s)

Digitized lines

Events

Static Objects (waypoints)

Additionally, the DTM, that in Figure 21 is colorcoded relative to the depth, might be coloured

relative to some other attribute, such as:

Density

Slope

Cleaning status



Figure 22 The DTM window, visualised with Pipeline inspection associated items

2.2.3.2 The Project Tree window

The „Project Tree‟ window is used to visualise the contents of the present NM3 project. The

contents are sorted in a number of headlines, such as „Surveys‟, „Toppings‟, „Palettes‟,

„Colormodes‟ etc. Furthermore a large variety of functions are available from here: by right-

clicking on the different entries, the associated menu-items will appear as it is visualised as an

example Figure 23 below, in connection with the present „Survey‟ menu, left (Kristin.db) and

with the „Digitized Line‟ menu (right).



Figure 23 The Project Tree window, „Survey‟ menu (left) and „Digitized Lines‟ menu (right)

In Figure 24 below, all the major entries/headlines (Events, Videos, Track) have been exploded

and explained.



Figure 24 Project Tree Window (with Pipeline inspection entries), explained

The different entries/headlines in the „Project Tree‟ are as follows (note that the sequence and the

actual contents might be different from project to project):

3D Model Manager: lists all 3DS objects loaded into the project

Project: Shows the name of the present NM3 Project

o Surveys: List all surveys/DTMs currently loaded into NaviModel3. Several DTMs

can reside in NM3 simultaneously. Right-click on one of the DTMs will invoke the

surveys menu

Source files: lists source files for each DTM currently loaded into NM3

Regions: lists cleaned regions for each DTM currently loaded into NM3

o Toppings: list all toppings currently loaded into NM3

Digitized Lines: lists lines created using the digitizing tool in NM3. Right-

click on the entry will invoke the digitizing menu (shown above in Figure

23, right

Pipe tracker: lists pipe tracker information currently loaded into NM3

(subentries: files, ranges, pipe fixes). Right-click on the entry to invoke the

pipe tracker menu

Pipes: lists all pipes currently in the project. Right-click on the entry to

invoke the pipe menu

Events: lists event information currently loaded into NM3. Right-click on

the entry to invoke the events menu

Videos & tracks: lists all videos with associated tracks currently residing in

NM3

Runlines: lists runlines currently in the project. Right-click on the entry to

invoke the runline menu

Displaylines: lists displaylines contours currently in the project. Right-click

on the entry to invoke the displaylines menu

Contours: lists contours currently in the project. Explode the entry to see all

contour-lines for each contour set. Right-click on the entry to invoke the

contour menu

AutoCAD: lists AutoCAD information currently in the project. Right-click

on the entry to invoke the AutoCAD menu

o Static Objects: list all static objects currently loaded into the project. These could be

associated with a waypoint

o Camera: shows a list of all camera position defined in the project. Typically these

have been generated with the camera tool (see chapter 2.2.2.3 for details)

o Online: shows information associated with NM3 being used as an online 3D

visualisation tool, if applicable

o Profiles: shows information associated with profiles currently in the project,

typically generated on the basis of digitized lines

o Palettes: shows a list of all palettes currently defined in the project



o Color Modes: shows a list of all color modes currently defined in the project

2.2.3.3 The Object Properties window

The contents of the Object Properties window will change depending on the item selected the

Project Tree window. Figure 25 below visualizes an explanation to the contents of the window

associated with a DTM (Survey).

Figure 25 The Object Properties window – DTM properties explained

Even though the figure is associated with a DTM entry, many of the items dealt with here are

common for the various „Object Property‟ types. As is the case with the DTM property panel, the

items have generally been rigorously sorted and, if necessary ordered in headlines, in order to

ease the detection and recognition of the various items included.

One of the guiding principles for the design of NaviModel3 has been to enhance user friendliness

by making the menus, panels as well as the different windows, easy to learn, easy to remember,

efficient to use, understandable and satisfactory to use.

The different entries/headlines in the „Object Properties‟ window visualised in Figure 25 are:

General:

o Visible: option used to toggle visible status of the object in question. This can also

be accomplished by right-clicking on the DTM entry in the „Project Tree‟ window

and choosing option „Hide‟ in the „Survey‟ menu

o Draw Palette: option used to toggle visible status of palette on the DTM window

Model Information:

o Path: visualises the path of the object

o Number of beams: visualises total number of beams (depths) in the dataset. This

includes deleted beams/depths)



o Cell size: shows the cell size of the model

Surface:

o Geometry Mode: shows presently selected model type. It furthermore facilitates

changing model type from a drop-down-list that shows all currently available types

(average, minimum, maximum and Interpolated average (optional))

o Color Mode: shows the color mode of the terrain. A drop-down-list allows

alteration between the ones available (depth, density, slope, cleaned regions,

difference from and kp)

o Opacity: shows the currently selected opacity of the terrain surface

Tool Tip Window: shows a dedicated help text associated with the currently highlighted

item

Figure 26 The Object Properties window – Pipe properties explained

The different entries/headlines in the „Object Properties‟ window visualised in Figure 26 are:

Cover Calculation:

o Fuzz Factor: Defines the (minimum) cover thickness for the pipe to be flagged as

covered. The value can be positive as well as negative. A negative value will report



the pipe covered prior to it being actually fully covered, whereas a negative value

will not report it covered until it is actually covered with the value stated

Cross Profile Export Options:

o Interval: Expresses the distance between points in a cross profile export

o Width: Expresses the total width of a cross profile to be exported

o Thickness: Used to define how far away from the actual (cross profile) line, points

can be selected and projected onto the line for a cross profile to be exported

o Points: Number of points in the cross profile. Note that the interval property

multiplied with the points property will always result in the width property,

regardless of the sequence in entering

General:

o Visible: Option used to toggle visible status of the pipe object in question. This can

also be accomplished by right-clicking on the pipe entry in the „Project Tree‟

window and choosing option „Hide‟ in the pipe menu

o Path: Here the path of the pipe information generated is visualised (for information

only)

o Diameter: Defines the default diameter of the pipe

o Delta KP: Defines the distance between the nodes of the pipe (unit is km)

o Min KP/Max KP: Defines/visualises the start and stop KP values of the present pipe

object

Pipe Tracker Alignment:

o Filtered line: Option used to define whether to align to pipe tracker information

(„False‟) or to filtered line (Kalman filter) („True‟)

Runline Alignment:

o Below Seabed: In case the pipe is (horizontally) aligned to the runline, the option

defines the burial (in meters) of the pipe object

Visualisation:

o Texture: Here it is possible to define whether to apply texture mapping to the pipe

object. The file „pipetexture.jpg‟ in the NaviModel3 bin-folder is used for this. See

below for two different pipetextures

o Points: Facilitates toggling on/off between showing points (green in drawings

above)

o Tube: Facilitates toggling on/off between showing tube (textured object in drawings

above)



Tool Tip Window: shows a dedicated help text associated with the currently highlighted

item

2.2.3.4 The Job List window

The Job List window displays the all background processes currently being conducted by NM3, in

sequence. In general terms, the job listed as the topmost is the one that is currently being

conducted. If a series of jobs are being started simultaneously, the sequence is however not always

that simple as can be seen below in Figure 27 left, that shows the window while importing a series

of bathymetric data. Figure 27 right shows how it is possible to stop an ongoing job by right-

clicking on it and choosing the „Stop‟ option.

While it is worth keeping an eye on the job list, to monitor the progress, the user should also be

aware that what is being listed is really background processes; it is consequently possible to

continue working with NM3 and to add new processes to an already populated list.

Figure 27 The Job List window

2.2.3.5 The Log window

The Log window visualises the history of all actions being performed by NM3 since the last time it

was started (see Figure 28 below). This includes, as can be seen in the figure, output from some of

the NM3 functions, such as volume calculations conducted from a displayline in the „Project Tree‟

window.



Figure 28 The Log window

2.2.3.6 The History window

The History window contains a list of all actions being performed by NM3 that can be

undone/deleted (see below in Figure 29). Pressing the arrow-left will undo last action, whereas

pressing arrow-right will redo last action (if applicable).

Figure 29 The History window



2.2.3.7 The KP Axis window

Figure 30 The KP-Axis window

As visualised above in Figure 30, the KP-axis window can a. o. visualise runline range, dedicated

event profile and pipe status information. The latter include items like: freespan, exposed pipe,

covered pipe and status (options are „OK‟ and „NA‟).

It is possible to select/deselect which runline information, event information and pipeline

information, to display. When events have been loaded into NM3, it is furthermore possible to

determine which event-types to display.



Figure 31 The Event Profiles View in the KP-axis window

For events in particular, as can be seen in Figure 31 above, each manual event-type loaded will

have a line in the Event profile and each event of the type will be represented by a vertical line on

the line at the particular KP-value of the event. Initially all manual events loaded will be sorted and

displayed in the KP-axis window. Subsequently it is possible to deselect which events (as well as

other items available) to visualise – by choosing menu item „Show‟. The window below in Figure

32 will pop up facilitating selection of which event-types to show in the KP-axis window. Note

that the list is alphabetically ordered.

Also observe that the items available in the list will depend on what items have been loaded in and

generated as toppings in NM3.



Figure 32 Show Ranges, Pipeline inspection job (left) and Pipeline inspection job with events (right)

2.2.3.8 The View Settings window

The „View Settings‟ window given below in Figure 33 below visualises and facilitates alteration of

the view settings of the DTM window of NM3. The different settings are divided into

headlines/items such as „Depth Contours‟, „DTM (Surface)‟, „Environment‟, „Light‟ and „Raw

Points‟ as can be seen in the figure.



Figure 33 The View Setting window, explained

The different entries/headlines in the „View Settings‟ window visualised in Figure 33 are:

Advanced:

o Clever Splitting: Optimization of display regarding splitting of nodes

o Frame Timer: update rate of DTM window. Default value is 10 ms

o Maximum Number of Cached Nodes: When moving fast in the DTM window and

this defines the maximum number of cached nodes, with respect to node clear age



o Node Box Mode: this function can facilitate drawing of a box around nodes in the

Quad Tree for diagnostic purposes (choose between „none‟, „nodebox‟ and

„databox‟

o Node Clear Age: Defines how long NM3 should keep nodes outside the visualised

window. The factor is multiplied with the frame timer value to accomplish the age

in seconds. Default value is 20 and should not be changed

Camera:

o Draw North Arrow: facilitates toggling on/off of the north arrow in the DTM

window

o Draw Target: facilitates toggling of camera target (visualisation of xyz axis of the

coordinate system in the center of the view) in the DTM window

o Target Size: in pixels. Default value is 100 pixels

Depth Contours:

o Contour Line Step: contour interval in meters for live contours. A value of 0 will

disable drawing of live contours

DTM (Surface):

o Fill Secondary: toggling of filling of neighbouring points. Neighbouring points are

cells with no observations in them that are neighbours to primary cells (cells with

observations). For visualisation purposes only

o Linear Filtering: toggles linear filtering on/off. Linear filtering will tilt each cell

relative to the value of the neighbouring cells. No filtering will show each cell as a

horizontal plane. For visualisation purposes only

Environment:

o Background: here definition of background color of the DTM window can be

defined. The value is used if the background is solid (no sky: see below)

o Detail Level: in the DTM window. Choose a lower detail level if the computer

cannot keep an appropriate frame-rate

o Sky: when enabled, NM3 will draw sky as background for the DTM window. AT

the same time, this will disable the background colour defined above

o Subsea look: when enabled, colors will be faded at a distance to imitate a subsea

look, in the DTM window

Light:

o Azimuth: here the direction of the sun light can be defined relative to north. Default

value is -45 degrees

o Diffuse: defines diffuse light range in degrees. Diffuse colors range from original

color at specular edge down to black color (at degrees)

o Enabled: toggles light on/off

o Height: height of the light source in degrees relative to the horizon. Default value of

70 degrees.

o Specular intensity: defines how white, in percent, the terrain is when oriented

directly towards the light source. Default value is 50%



o Specular opening: defines the specular light opening angle, with a value of 0

meaning that no specular light is required

Miscellaneous:

o Draw Profile Grid: when enabled, a profile grid is visualised in the DTM window

around the center of the view (the camera point)

o Surface Grid Position: in case of a surface grid, this option defines the vertical

position of the grid (in meters)

o Surface Grid: toggles the surface grid on/off

o Triangle Grid: when enabled, the triangles that show the highest level of detail in

the Quad Tree is visualised. The triangles are the TRNs that form the DTM at

different level of detail

o Water Surface Transparency: if enabled the water surface is displayed at the vertical

position defined under water surface and with the transparency specified here, with

0% is totally invisible water surface and with 100% giving a totally opaque water

surface

o Water Surface: toggles visualisation of the water surface on/off

o Water Surface Depth: defines the vertical position of the water surface

Overlay:

o Legend: toggles legend in upper right corner of DTM window on/off

o Target Location: toggles target location in lower left corner of DTM window

on/off. The information includes date/time, KP, Easting, Northing and depth of

target position

Raw Points:

o Color Mode: when „Draw Raw‟ is enabled (see below) the option facilitates the

definition of whether or not to visualise raw per block (all data originating from a

single file are given the same color) or by depth (data are colorcoded relative the

depth value, using the definition associated with the colormode „depth‟)

o Draw Raw: toggles visualisation of raw bathymetric observations on/off

o Raw Points size: defines size, in pixels, of the individual raw bathymetric

observations

o Raw Points windowx_m: defines size of the window in the x-axis (Easting)

direction

o Raw Points windowy_m: defines size of the window in the y-axis (Northing)

direction

o Show Deleted: when enabled, also deleted observations will be visualised in the

raw data window

o Show Statistics: when enabled, statistical information related to the observations

visualised in the raw data window will be shown in the DTM window. The statistics

include: file-name, number of points, average depth, difference of average depth (in

case data from more than one file is presently shown, maximum and minimum



depth values, median depth value as well as standard deviation of the depth

currently in the window

Tooltip window: visualises a help-text associated with the item currently highlighted

2.2.3.9 The Video windows

Figure 34 Video windows

The Video-window can be opened from the menu-item „View – open all video windows‟. This

action will also open the Events window. Alternatively, it is possible to, one-by-one, open the three

video windows (port, starboard and centre) as well as the event window.

Once the video windows are opened, it is possible to define the path, where NaviModel3 should

locate the time-stamped folders containing the video information. To do this, right-click in the

Video-entry in the Project Tree window and choose „Manage Video Folders…‟ as shown below in

Figure 35. The window to the right will open, facilitating the definition of one or more video

folders.

Figure 35 Video Folder



Alternatively the contents of a folder can be dragged-and-dropped onto the DTM-window of

NaviModel3.

The Video window is linked to a track. This track information can either be loaded directly as a

topping or it can be loaded as part of the video folder drag-and-drop. In the first case, data can be

exported from NaviEdit as *.dat or *.etr files. In the second case data could be exported from

NaviEdit as *.csv files or a track already residing in the video folder could be used. Either way

however, NM3 will link the time associated with the track information to the time of the video. So

by clicking on the track in the DTM-window, the cursor position (which is the current position on

the track (the ROV position)) will be visible (as a cursor) and the video will move to the same

position with respect to time (see Figure 36 below).

Figure 36 NM3 Video windows and Track w. Cursor on DTM window

The Events window is basically constituted by the EventEdit software. EventEdit can be executed

as a stand-alone application or as an integrated part of NaviModel3. The functionalities when

integrated into NaviModel3 and when executed as a stand-alone application are identical.

The EventEdit tool with an eventfile loaded is visualised below in Figure 37. It appears that the

user interface is constituted by the so-called „Fields View‟ area. In the „Fields View‟ area, the

various event fields can be visualised in a matrix structure, much like what is known from various

spread-sheets. Details on the functionalities of the EventEdit tool are given in the two dedicated

eventing manuals: „Online Eventing Manual‟ and Offline Eventing Manual‟, that both can be

found on the EIVA Training and Documentation site: http://download.eiva.dk/online-

training/index.htm. Loading of events is described in chapter 2.3.3.9 below. Observe that Figure 36

above shows a visualisation of events in the DTM window.

http://download.eiva.dk/online-training/index.htm

http://download.eiva.dk/online-training/index.htm



Figure 37 EventEdit, with a NaviPac eventfile (*.log) loaded

2.3 Special Functions & Methods

When dealing with a post-processing task associated with pipeline inspection based survey data, a

series of special functions and methods within NaviModel3 must be described:

Model Types and Interpolation Methods

Generating the DTM (the Quad Tree principle and Indexing)

Using Toppings

Cleaning Methods

Digitizing Methods

Pipe Functions

Exporting Functions

A series of other functions and methods could be dealt with in connection with a NM3 based post-

processing task, such as Contouring methods and Volume Calculation methods. These will not be

handled in the present context, due to the nature of the subject. Instead references are given to the

„Bathymetric Postprocessing Tutorial‟ that can be found in the dedicated NM3 training and

documentation site: http://download.eiva.dk/online-training/NaviModel3.htm

http://download.eiva.dk/online-training/NaviModel3.htm



2.3.1 Model Types and Interpolation Methods

A Digital Terrain/Elevation Model (DTM/DEM) can be regarded a generalization of the observed

bathymetric data, with generalization being defined as the process of reducing the amount of detail

in a map in a meaningful way, with respect to scale.

At the same time, since total model coverage of the area of interest is often a requirement,

observations must often be extended beyond the observations.

Whereas different Geometry Types are used to generalize on the basis of the bathymetric

observations, Interpolation Methods are utilized to generate qualified information, based on the

model generated, in areas where no observations have taken place.

2.3.1.1 Geometry Types

NaviModel3 supports two different model types:

The Triangulated Regular Network (TRN) Model Type

The Triangulated Irregular Network (TIN) Model Type

2.3.1.1.1 TRN Modelling

The TRN geometry type within NaviModel3 is based on square cells with a given cell size. The

cell attribute value (z-value or depth value) can either be arrived at by averaging all the

observations within a single cell or by taking the minimum or maximum depth value respectively.

The TRN modelling method produces all three model types by default. So when generating an

NM3 DTM/DEM, the first step would be to generate these three model types on the basis of the

input data and on the specified cell size.

Figure 38 TRN Squared Array with primary cells as squares

The TRN cell array looks as visualised in Figure 38 above. The centre of each cell is visualised

with a green dot. Each cell has its own attribute value not associated with the attribute of the

neighbouring cell. The model will therefore appear to have steps and will certainly not appear



smooth. With squares representing the attributes it is in other words not possible to make the

desired seamless transition between the cells.

To assist in this, each cell is divided into four triangles as it appears in Figure 39 below. In addition

the corners of each cell (visualised with a yellow dot) is given an attribute value that is representing

the attribute values of the four neighbouring cells. For an average model, the point will be given

the average value for an average model, whereas it will be given the maximum and the minimum

of the four neighbouring cells for maximum and minimum models respectively. By using triangles

it is ensured that each piece of the mosaic surface will fit with its neighbouring pieces since the

surface of each triangle is defined by the elevations of the three corner points.

When all three corners of each triangle have now been assigned an attribute that is linked to the

neighbouring points, it is possible to create the desired continuous seamless transition between the

cells, represented by the triangles, within the model.

Figure 39 Generating a Triangulated TRN on the basis of the squared cell model

The TRN-based model types can be used to generate and export gridded values and bitmaps even

if the desired cell size and orientation is not identical to that of the model. In general terms, the

present TRN model type selected can be regarded a look-up table and the export routine will thus,

by sending the XY-values, make NM3 return the associated attribute value from the present TRN

model type.

The generation of contours is also based on the TRN model. For each depth value related to the

contour interval and the depth range of the model, the contour routine will search the model and

find places with attribute values equal to the desired contour values. For each contour the points

returned must now be connected taking into consideration the basic requirements to contouring,

such as:

Contour lines cannot cross each other

Contour lines cannot stop in the middle of the model (unless there are no data available)

Contour curves cannot split in two



Contour curves cannot follow the top of a ridge or the bottom of a depression

Finally, it is worth noticing that the principle described in the above is valid for the highest

resolution of the model that is also equivalent to the lowest level of the Quad Tree (see chapter

2.3.2.1 for information about Quad Tree Principles). For higher levels of the Quad Tree, the

principle is identical in terms of methods for visualisation of the model.

2.3.1.1.2 TIN Modelling

A TIN is a terrain model type that creates a set of continuous, non-overlapping, connected triangles

(faces), based on a so-called Delaunay triangulation of irregularly spaced observations. The corners

of the triangles are identical to the observations and within each triangle the surface is usually

represented by a plane. Unlike the TRN geometry type, a TIN model will allow for different

density in the data model in different areas. The size of the triangles can therefore be adjusted to

reflect the degree of relief in the surface to be modelled, provided more data has been gathered in

areas of variable elevation characteristics.

Similar to the TRN geometry type, the use of triangles ensures that each piece of the surface fits

the neighbouring pieces, and it is thus possible to create the desired continuous seamless transition

between the triangles, within the model.

The variable and thus efficient data density within the model can bring in yet another advantage, in

that it ensures a very efficient way of storing the model. The TIN model shown below in Figure 40

is generated with approximately 13.000 triangles and is occupying less than 0.5 Mb, whereas the

TRN geometry type, based on identical data, occupies 34 Mb.

Figure 40 TIN model within NM3, based on single beam observations in a harbour



The use of TIN triangles works best in areas with sharp breaks in slope, where the edges of the

triangles can be aligned with breaks for instance along ridges. For TIN modelling to be efficient,

this requires therefore that data has been collected in significant positions, such as highs and lows

along break lines as well as on top of ridges and in depressions. This can, for obvious reasons, not

be fully obeyed in connection with hydrographic surveying. It is therefore important, when the aim

is to use TIN modelling in the post-processing, to use knowledge about the nature/roughness of the

seabed to be included in the pre-survey planning considerations. This could for instance result in

different line-spacing in different areas to accommodate for a sensible relationship between data

density and seabed roughness. The TIN model shown above in Figure 40 is based on single beam

observations. Observe that points are almost equally spaced, indicating a flat seabed.

2.3.1.1.2.1 Principles of Delaunay Triangulation

The Delaunay triangulation is a triangulation method, that, in NaviModel3, is used to ensure that

the angles in the triangles are as close to 60 degrees as possible, with the observation material at

hand, in order to ensure that each position in the plane of the triangles are as close to the

observations as possible. This is basically done by introducing the requirement that a circumcised

circle between the corners of a triangle must not contain any other point; it must be an empty circle

with respect to the other observation points.

Figure 41 Principle of Delaunay Triangulation

The principle is visualised in Figure 41 above. In the example, a simple triangulation must take

place on the basis of four observations. By definition, the outer polygon ABCD is fixed. So the

http://mathworld.wolfram.com/Triangulation.html



task for the Delaunay algorithm is to figure out which of the two options, left (with line AD) or

right (with line BC) in the figure, should be chosen. Intuitively, the option right also appears right,

since the sides of the triangles have almost the same length, whereas this is not the case to the left.

As can be seen in the figure, both possible circumscribed circles contain the fourth point in the

option left whereas this is not the case in connection with right. So therefore option right is chosen

by the Delaunay algorithm.

2.3.1.1.2.2 Special TIN Model Functions

Once a TIN model has been created in NM3, the various TIN model functions can be invoked from

the „Survey‟ entry of the „Project Tree‟ window by right-clicking on the model as visualised below

in Figure 42.

Figure 42 The Survey Menu, TIN Models

Of particular interest are the functions that will allow modification of the Delaunay triangulation:

Remove triangles mode: will allow the user, through manual selection with the cursor, to

delete single triangles

Remove triangles with lines longer than: an automatic deletion feature that will allow the

user to enter a maximum allowed line length. Any triangle with at least one line longer than

this maximum value will be deleted

Flip Triangles Edge Mode: will allow the user, through manual selection, to change the

triangulation on a single triangle, by flipping the edge

Remove Beam Mode: this function facilitates the deletion of a single observation, through

manual selection

2.3.1.2 Interpolation Methods

Interpolation is used to predict the values of attributes (depths) in areas with no observations

available, but within the area covered by observations. Predicting values outside this area is termed

extrapolation.



When data is abundant, like in connection with areas observed with multibeam techniques, most

interpolation techniques will yield (close to) similar results. When data are sparse, however, like in

connection with single-beam surveys, the method for interpolation can be critical.

NM3 supports two different methods for interpolation/extrapolation:

Interpolated Average

TIN Modelling

2.3.1.2.1 Interpolated Average

In connection with TRN models, NM3 facilitates the method of performing „Interpolated Average‟

models. Even though the phrase is „Interpolated‟, it actually covers the fact that an interpolation is

taking place internally in the surveyed areas, whereas extrapolation is taking place on the outside of

this area.

NaviModel3 will, on the basis of primary cells (cells that contain observation information),

extrapolate to the neighbouring cells by using a predefined search radius. In cases where primary

cells are completely surrounding the secondary point in question and within the search-circle, this

method actually results in an interpolated result. Note that the method is termed „Interpolated

Average‟ because the input attributes from the primary cells are associated with values from the

average TRN model.

Figure 43 Principle of Interpolated Averaging: Extrapolation left and Interpolation right

This is all visualised in Figure 43 above. The primary cells are indicated with a green dot, whereas

the secondary cell in question is represented by a red dot. Around the secondary cell a circle is



drawn with the predefined search radius. This is called the search circle. The routine will search for

primary cells in all directions inside the search circle. If more than one primary cell is found in a

given direction, the closest will be used to determine the value/attribute of the secondary cell. Once

all directions have been investigated and at least one primary cell has been found inside the circle,

the value for the secondary cell in question is found as a weighed average of the values/attributes

of the primary cells found. This weighing is performed as the inverse to the square of the distance

between each of the primary cells and the secondary cell in question. The method is thereby taking

Tobler‟s first law of geography into consideration “Everything is related to everything else, but

near things are more related than those far apart”. The value/attribute of the secondary cell can in

other words be calculated as:

i

n

i i

n

i i

Apd

d

As *1

*

)1

1

12

12

, with

As = attribute value of secondary cell

Api = attribute value of primary cell n

n = no. of primary cells found

di = distance from secondary cell to primary cell n

The first part of the equation is used to normalise the outcome for the attribute of the secondary

cell, whereas the second part constitutes the weighing of the observations relative to the inverse of

the square of the distances.

The method can be considered a dedicated case of the Inverse Distance Weighing (IDW) method

that by some is considered the workhorse of spatial interpolation. IDW achieves the desired

objective of creating a smooth surface whose value at any point is more like the values at nearby

points than the values at distant points.

Note also that the method is not used to change values of primary cells in NM3. Consider however,

if it was really used to try to do this: the method would then actually arrive at the input values for

the primary cells because the weight would be infinite with a zero distance. IDW is therefore often

described as an exact method of interpolation, since the results are true to the input as opposed to

an approximate method that allows the result to deviate from the input in the interest of perhaps a

higher degree of smoothness of the model.

The IDW method can often be considered particularly useful in connection with Hydrographic

survey data. A weighed average that is never negative will always return a value that is between

the limits of the measured values. This means that the method will never generate new undesired

highs and lows, not even when extrapolating from the outer skirts of the model. This can however

sometimes produce counterintuitive results. If for instance a slope is indicated by the data on the

outside of the model, the IDW method will not continue this trend but instead arrive at some

average values outside the area of the data points. This is visualised below in Figure 44. In the



foreground is a slope with the contours showing the area that contains observations. The sloping is

discontinued in the Interpolated area. As opposed to this, observe how the extrapolation beyond the

flat area in the background clearly appears to be intuitively correct.

Figure 44 TRN Extrapolation beyond observations

„Interpolated Average‟ models are most useful in connection with multi-beam surveys but can also

successfully be used with single-beam data.

The „Interpolated Average‟ function is invoked in NM3 from the „Survey‟ entry of the „Project

Tree‟ window by right-clicking on the model and choosing the menu-item „Generate Interpolated

Average map‟ as visualised below in Figure 45.



Figure 45 Survey Menu, TRN Models - Generate Interpolated Average

Choose an appropriate value for the search circle when prompted (for „Search radius in cm for

interpolation‟) as shown below. Observe that the default radius will be 5 times the cell size of the

model; in the present context this is equivalent to 125 cm. Once an appropriate value has been

entered, press „OK‟ to proceed.

Observe that for multi-beam as well as for single-beam surveys, an appropriate value for the search

circle should be slightly larger than the width of the largest distance between observations, in a

direction perpendicular to the sailing direction. This will ensure that interpolation, not

extrapolation, will take place on the inside of the model. If this is not observed, „steps‟ in the model

must be expected where the extrapolated values from one side meets extrapolated values from the

opposite side. In particular in connections with single-beam survey, where the relative number of

primary cells is expected to be small, this rule of the thumb is important to obey.

NM3 will now start generating the Interpolated Average model. Once this has been accomplished,

it will be available in the „Model Type‟ drop-down-list in the „Properties‟ window associated with

the model.



Figure 46 Geometry Mode/Model Type changed from 'Average' (left) to 'Interpolated Average' (right)

2.3.1.2.2 TIN Modelling

Triangular Irregular Networking can, besides being considered a modelling method, also be

considered an interpolation method. As opposed to the „Interpolated Average‟ method described

above however, TIN cannot be used to extrapolate attribute values outside the area of observations.

Like the „Interpolated Average‟ method, the TIN method can be considered an exact method, since

TINs incorporate the original data points. However the TIN goes further than the „Interpolated

Average‟ model, given the fact that the data points are identical to the observations. This is not the

case for „Interpolated Average‟, since this extrapolation method is based on an average model and

not on the raw observed data.

Having said this, however, it appears evident that the TIN has its limitations in the fact that, in

principle, no generalisation of the data will take place. All observations are used and this clearly

makes it more useful in connection with single beam surveys and when handling theoretical

models, where the amount of data is limited.

A special case for TIN modelling is the 3D theoretical model that often must be employed to

define requirements to dredging tasks. With the adequate data, defining the requirements to the

area it is a simple task to generate a TIN that yields a complete and well-organized representation

of the area. This can normally not be accomplished with a TRN model.

2.3.2 Generating the DTM

Within NaviModel3, data is, in general terms, organised in a so-called Quad Tree structure. The

process of placing data in this structure is called indexing.

2.3.2.1 The Quad Tree Principle

The Quad Tree structure is used to organise TRN models within NaviModel3. A Quad Tree is a

tree-based data structure in which each internal node has up to four children. Quad Trees are

http://en.wikipedia.org/wiki/Tree_data_structure



commonly used to partition a two dimensional space by recursively subdividing each level into

four quadrants or regions (see Figure 47 below).

Figure 47 The Quad Tree Principle

In a Quad Tree, records are stored in locations called leaves. The name originates from the fact that

records always exist at end points; there is nothing beyond them. The 1st level is also sometimes

identified as the root. Branch points, on the other hand, are called nodes. The order of a tree is the

number of branches (called children) per node. In a Quad Tree, there are always four children per

node, so the order is 4. The number of leaves in a Quad Tree is consequently always a power of 4.

The number of access operations required to reach the desired record is called the depth of the tree.

Figure 48 below visualises a Quad Tree of depth 4. This is basically just another way of visualising

the tree given in Figure 47 above.

Figure 48 Quad Tree with Leaf Level

In a practical Quad Tree, there can be millions of records. As can be seen in the figure, not all

leaves necessarily contain a record and the same is actually the case for nodes. In the latter case,

the node does not have to be subdivided. When a leaf does not contain a record it is called a null

record. In the example shown here, seven out of 64 leaves are nulls, indicated by open circles.

The cells may be square or rectangular, or may have arbitrary shapes. All forms of Quad Trees

however share some common features:



They decompose space into adaptable cells

Each cell has a range of capacity, defined by a minimum and a maximum value. When the

limit is reached, the cell splits downwards in the tree or merge upwards to the previous

level

The tree directory follows the spatial decomposition of the Quad Tree

Each node must contain the following information:

4 pointers: quad[„NW‟], quad[„NE‟], quad[„SW‟], and quad[„SE‟] – in NM3 this is defined

as E, N and size

a point, which in turn contains:

o a key; usually expressed as x-, y-coordinates

o an attribute value; for example a depth or a series of depths (maximum, minimum,

average)

The NaviModel3 adaption of a Quad Tree structure is based on square cells that decompose down

to the leaf level, which is identical to the cell size defined when generating the DTM. The depth of

the Quad Tree is in principle based on a) the area covered by the data and b) the cell size. However

in NM3, the depth is defined as 32 levels and data is then filled from the leaf level and upwards.

On the leaf level, the attribute values are defined as average, maximum and minimum values

respectively of the observations found in the cell. Higher up in the hierarchical Quad Tree system,

the attribute values are defined as average, maximum and minimum respectively of the values in

the lower branch level.

The higher orders of the Quad Tree are primarily used for visualisation purposes: the higher the

scale the lower the requirements to the resolution and thereby the higher in the Quad Tree the data

can be assembled. When exporting from a DTM, the leaf level data are normally used to define the

various attribute values for the export. The cell size for the exporting is however used to optimize

the exporting: if for instance the cell size for the export is 2 times the cell size of the model, then

the exporting function will actually collect attribute values from the level above the leaf level. This

will potentially speed up the export by a factor 4.

In NaviModel3 a database that encloses the hierarchical structure of the Quad Tree structure has

been entrenched in a single file solution. This solution has a series of advantages relative to the

classical file structure, such as:

the speed of various search functions within NM3 (exporting functions etc.) is increased

copying and back-up speed of a project is increased

the single file solution facilitates multiple access to a database

the system does not jeopardise/slow down general file management functionalities on a

hard-drive

Since the size of such a database can often extend to a considerable size, it should be considered to

generate databases only on NTFS drives, since FAT32 drives has a file size limit of 4 GB.



2.3.2.2 Indexing a DTM

The Digital Terrain models can be built inside NaviModel3 by dragging-and-dropping from

Windows File Explorer onto the DTM-window. The program supports input with the EIVA

proprietary formats *.ned, *.sbd as well as alternative formats, such as *.xyz, and *.all files.

Dropping one or more files onto an empty project will force NaviModel3 to start indexing for a

TRN model, whereas dropping onto an already generated/loaded terrain model will either append

the information from the data files to the current model or the data can be used to generate a new

Terrain Model.

Observe that when dropping ASCII xyz-files with the extension xyz, NM3 will prompt to generate

a TIN model as shown below. A TIN model is not organised in a Quad Tree structure and is

therefore not indexed.

Once NaviModel3 starts indexing a TRN model for the first time, a dialog will request for

information regarding the DTM to generate. The information required is comprised by a)

requirements to cell size of the resulting terrain model and b) information related to the path and

name of the file of the DTM, as visualised below in Figure 49.

Figure 49 DTM settings, Path, filename and cell size selection

Figure 50 Warning regarding drive type if not NTFS

As can be seen Figure 50 above, NM3 will routinely issue a warning regarding the drive type, in

case this is not NTFS. Press „Yes‟ to continue if the model is not expected to exceed the limit.



When clicking „Ok‟ on the DTM Settings dialog, the indexing process will start, during which a

terrain database is being built on the hard-disc. Information related to the process is being

displayed on the Information bar as shown below in Figure 51 After indexing, NaviModel3 will

automatically go to the terrain in the DTM-window (left) as well as in the Job List window (right).

Figure 51 Indexing Progress visualized in the Information Bar and in the Job List window



Once the indexing is finalised, the DTM window will automatically move to the area in question

and select a scale that accommodates for the entire model to be shown, as can be seen below in

Figure 52. At this stage of the process the DTM is saved and any subsequent alteration committed

to it will be saved automatically in the location and with the file-name initially specified.

Figure 52 Indexed DTM repository in NaviModel3

2.3.3 Using Toppings in NaviModel3

Once the DTM has been generated, various toppings can be overlaid the terrain model in the DTM

window. In order to support a pipeline inspection post-processing task, toppings like pipe-

information, including pipe-tracker data, event-information, runlines, displaylines (including

AutoCAD based information), waypoints, chart definition series etc. would be of particular

interest. Also toppings like 3DS information, video information and track-information could

however be used in the post-processing phase.



2.3.3.1 Pipe Information

For a pipeline inspection post-processing task, the most important topping is obviously the pipe

topping. This can be loaded as a pipetracker file or it can be generated within NaviModel3. In the

first case, the pipetracker file can be exported from NaviEdit, and might actually originate from

pipetracker observations. Alternatively the pipe data might have been generated and placed

automatically in NaviEdit, based on multibeam information from an exposed pipe. Either way

however, the data must be exported in the dedicated *.pip format.

Pipe tracker data can be dragged-and-dropped onto the DTM window or they can be loaded from

the ASCII Import window. The latter can be applied when the format is not automatically

recognised by NM3.

Once the data has been loaded by NM3, it will be visualised in the DTM window (see Figure 53,

below right) and it will appear in the „Project Tree‟ window as an entry under the „Toppings‟ item

(Figure 53, left).

Figure 53 Pipe Tracker data loaded into NM3, 'Project Tree' window, left and DTM window, right

In the DTM window, the pipetracker information will be shown together with a Kalman filter line.

This line is based on the Pipe Tracker observations and the NM3 Kalman settings. If selected by

the user, the Kalman line can be used to place the pipe at a later stage of the process.



Figure 54 Pipe Tracker data shown in the KP axis window

In addition to this, the Pipe Tracker observations and the Kalman line can be shown in the KP Axis

window as visualised above in Figure 54.

See more details on how to use pipe toppings and how to generate a digitized pipe object in the

dedicated chapter 2.3.6, Pipe Functions below.

2.3.3.2 Runlines

NM3 is supporting the runline formats that are defined in and supported by NaviPac. This also

includes multiple runline, series of parallel runlines as well as crosslines. In some cases however,

in connection with pipeline inspection and offline eventing, it is advisable to only load a single

runline. Runlines can be dragged-and-dropped onto the DTM window or they can be loaded from

the ASCII Import window. The latter can be applied when the format is not automatically

recognised by NM3.

Start by opening the ASCII Import window from the menu item „File – Import…‟. It is now

possible to either browse for the file in question or to drag-and-drop it onto the ASCII Import

dialogue window. Once this has been accomplished, the window will appear as visualised below in

Figure 55, left. Highlight the „Runline‟ option in the list to the left and press the „New‟ button, to

indicate a new import template. Give it an appropriate name.



Figure 55 ASCII Importer

The template must now be modified to accommodate for the contents of the file. This is done by

defining the column in which the Easting, Northing and KP information is placed. It is also

possible to define items like number of header lines, separators and file extension. Be careful with

the definition of the extension. NM3 will use this setting to identify files with this extension and

load it with the template defined. The template now appears as visualised in Figure 55, right with

the actual contents shown in the bottom window and the columns selected displayed as

highlighted. Once the template is acceptable press the „Save‟ button in order to save the template.

Then press „Import‟ to read the runline into NM3. Note that if NM3 does not recognize an

extension, it will automatically open the ASCII importer dialogue window when a file is dragged-

and-dropped onto the DTM window.

Once a runline has been loaded into the DTM window, it will appear here, as shown below in

Figure 56. At the same time, an associated entry will appear in the „Project Tree‟ window under

„Toppings‟. A runline is normally green however when selected in the „Project Tree‟ window it

will change color to yellow as can be seen. Observe that the option „Show Projected Point‟ has

been enabled, with the consequence that the cursor position is projected onto the runline and the

corresponding positions (Easting, Northing, DAL, DOL and KP) are visualised.



Figure 56 Runline in NM3

2.3.3.3 Displaylines

NM3 is supporting the displayline formats that are supported by NaviPac. In NaviPac, the concept

of displaylines includes two different formats:

the *.dis format

the AutoCAD formats (including the *.DXF and the *.DWG formats)

The *.dis format is a simple ASCII format, that defines Easting, Northing and pen control in three

columns. The format is defined in http://download.eiva.dk/online-training/HD_Displayline.txt that

is part of the EIVA Training and Documentation site.

Within NM3, the *.dis displaylines are used for a variety of things, besides the simple visualisation

on the DTM window. They can be used as the basis of:

the exporting function

volume calculations

structured cleaning

When a displayline or a series of displaylines have been dragged onto the DTM window, they will

be visualised here as shown below in Figure 57. At the same time, an associated entry will appear

in the „Project Tree‟ window under „Toppings‟.

http://download.eiva.dk/online-training/HD_Displayline.txt



Figure 57 Displayline in NM3

A displayline is normally displayed with the color (and line style) defined in the file, however, this

can be altered in the „Properties‟ window as shown above in Figure 57, by choosing „True‟ to

option „Overwrite .dis settings‟ and altering the „Color‟ and „Line Width‟ options.

NM3 as well as the Helmsman‟s Display of NaviPac support AutoCAD files (*.dwg and *.dxf)

from version 2000 and older. These files are used for visualisation only. See an example in Figure

58 below. It is possible to change the visualisation of the layers within the file, by right-clicking on

it in the „Project Tree‟ window and choosing menu-item „Layers‟. The window „Layers‟ shown in

the figure to the right will appear with a list of all layers and an option to tick tem on and off

individually.



Figure 58 AutoCAD file in NM3

2.3.3.4 Waypoints

By default, NM3 does not support dragging-and-dropping of the waypoint files supported by

NaviPac. They can however be defined through the ASCII Import as described above in chapter

2.3.3.2 in connection with loading of runlines. So by defining a series of waypoint templates where

the two NaviPac waypoint extensions *.wpt and *.wp2 are specified, NM3 can be configured to

recognise these by default.

Waypoints can be used to display static objects in the DTM window. These can have a 3DS object

attached to it as visualised below in Figure 59. Observe the „Properties‟ window that contains

information about position as well as attitudes of the object. Also observe that it is possible to

enable visualisation of under keel clearance of the object by the relevant entering offset values. The

actual value is then shown under the object (10.6 m in the example).



Figure 59 Waypoints in NM3, with 3DS object attached

2.3.3.5 Chart Definition Series

Chart Definition Series can be generated in Imaging, typically on the basis of a runline. The

method applied for this is described in detail in the „Bathymetric Processing Tutorial‟ that can be

found on the EIVA Training and Documentation site. Chart Definition Series can be used in

connection with the exporting function.

In addition to loading a chart series by dragging-and-dropping, it is possible to generate a single

chart manually from the „Project Tree‟ window: Right-click on the „Toppings‟ entry and choose

menu-item „New chart series (.cdf)‟. A new „Chart‟ entry will appear under the Toppings item.

When right-clicking on this chart and by choosing the menu-item „New chart‟ a chart with the

extensions equivalent to the present view of the DTM window.

Figure 60 below shows a Chart Definition series loaded into NM3. Observe that the properties

given in the „Properties‟ window for items like „Cellsize‟, Image Format‟ and „Terrain Color‟ are

properties that are associated with the exporting function.



Figure 60 NM3 with Chart Definition series

2.3.3.6 3DS Information

3DS files can be dragged and dropped onto the DTM window. When doing so, a prompt a prompt

as shown below will ask the user whether the object should be placed in the scene at the current

(cursor) position. When pressing „Yes‟ a waypoint will appear in the „Project Tree‟ under the

Toppings item with the 3DS object attached. Alternatively, a „No‟ will place the 3DS object in the

„Project Tree‟ under he 3D Model Manager item.



3DS files are files generated utilizing the 3D Studio software package from AutoDesk. Within

NM3, the 3DS files can be used to visualise object, such as static objects, the track-cursor object or

online objects when NM3 is linked to NaviPac and used as a 3D real time display.

In such situations, the 3DS object must be associated with the object in question. To associate with

a track-cursor object, right-click on it in the „Project Tree‟ window and choose menu-item „Attach

nn.3ds‟ as shown below in Figure 61.

Figure 61 Attach 3DS object to a Track-Cursor object

Once this has been accomplished, the track and the cursor will appear as shown below in Figure

62. The track is visualised as a yellow line, whereas the track-cursor is visualised utilizing a 3D

model of an ROV.



Figure 62 Track and Track-cursor object with 3DS object attached

2.3.3.7 Track information

The track information can be loaded into NM3 either as *.dat or *.etr files exported from NaviEdit

or they can be loaded as part of a video folder, typically as a *.csv file. In the latter case, the file

can originate from NaviEdit or it can be originating from the video-software.

When dropping such a track file into the 3D view, NaviModel3 will load the file and place it under

the „Toppings‟ node in the project tree. If a video topping has already been loaded onto the project,

NM3 will automatically associate the video and the track information via the timing of the two

different topping types.

To move to the newly loaded track, right click the node in the project tree and click „Move to‟. The

track is split into separate lines when the time-span between two successive samples (or two

associated video samples) exceeds one minute – in such a case, NaviModel3 will sort all records in

the track file by time. The *.etr file shown below in Figure 63 contains three different tracks with

their start date and time as label.



Figure 63 Track files under Toppings node – observe that the track is split into 3 separate lines

Once the track file has been dropped into NaviModel3, it will be visualised in the DTM-window as

shown above in Figure 63.

2.3.3.8 Video Information

NM3 supports two different video capture formats: Visualsoft and NetMC. Video information can

be dragged-and dropped onto the DTM window. Once this has been accomplished, the video

information can be visualised as described in chapter 2.2.3.9, The Video windows above.

Alternatively it is possible, once the video windows are opened, to define the path, where NM3

should locate the time-stamped folders containing the video information. Details on this are also

given in chapter 2.2.3.9.

2.3.3.9 Event Information

NaviModel3 supports by default two different event formats: the EIVA proprietary eventing format

*.log and the Visualsoft eventing format with the extension *.csv.

When dropping an event log-file into NaviModel3, the „ASCII Import Form‟ window shown

below in Figure 64 will pop up. The user will have to choose the appropriate data-type (in the left

and the middle columns in the present context). Ultimately, when pressing the „Import‟ button,

import of the event file will take place.



Figure 64 ASCII Import form – Event Collection from NaviEvent

Now the various events will be visualised in the DTM-window and an event collection entry will

be given in the project tree under the „Toppings‟ node (see red arrow in Figure 65 below). The name

of the event collection will be identical to the name of the event-file. Further when opening the

EventEdit window in NaviModel3, the events will be shown here – with one line per entry/event.

Further details regarding events are given above in chapter 2.2.3.9 above.



Figure 65 NM3 – with EIVA Events

2.3.4 Cleaning Methods

A series of different cleaning methods are implemented in NaviModel3:

Point Edit 3D Cleaning

Flat Seabed Cleaning

Plane Cleaning

The cleaning methods can be invoked from two different locations a) from the „Tools – Plane

Cleaning‟ menu-item as described above in chapter 2.2.1.3, The Tools menu and b) with respect

to a displayline, that then will form the basis of the so-called structured cleaning.

In addition to the three built-in cleaning methods, NM3 facilitates the inclusion of dedicated

cleaning tools through the menu-item „Tools – Point Cleaning – Edit Plugins‟. In this context, a



tool is an executable file that reads a point file (from NM3) and writes back the (edited) result to

the same file and consequently back to NM3, once the dedicated cleaning has taken place.

2.3.4.1 Structured Cleaning

Structured Cleaning is initiated from a displayline (.dis) object in the „Project Tree‟ window.

Right-click on the displayline in the window and choose the menu-item „Create Structured

Cleaning Objects‟ as shown in Figure 66, below left.

Figure 66 Create Structured Cleaning (left) and Choose Structured Cleaning method (right)

This action will subdivide the displayline object into a series of areas that, by average, contain 2

million points. These new areas are available below the displayline object in the „Project Tree‟

window as shown in Figure 66, right and will also be visualized in the DTM window. By right-

clicking on these objects, it is possible to choose either „Point Edit 3D‟ cleaning or „Plan

Cleaning‟ from a menu. Once a cleaning has been conducted, a note will be available on the

object in question as shown below (left) as well as in the DTM window, below right. The outline

of the area will furthermore change color from red to yellow when one type of cleaning has been

conducted and further on to green when both types of cleaning have been carried out.



2.3.4.2 Point Edit 3D Cleaning

When invoked from the menu item „Tool – Plane Cleaning Points edit 3D‟, the „Point Edit 3D‟

cleaning tool will visualize a north/south oriented square geographical selection tool in the DTM-

window (see below). The white square can be resized by simultaneously pressing the CTRL-

button and rolling the mouse wheel.

Once the selection is acceptable and the user presses the left mouse-button, the EIVA Point Edit

3D cleaning tool will open.

Selection of the area to be cleaned can also be performed via the Structured Cleaning tool as

described above in chapter 2.3.4.1.



Figure 67 Point Edit 3D cleaning

The 3D-based cleaning, in which the user can see portions of the model area includes a series of

tools that can all be easily accessed by use of the mouse (including the wheel of the mouse), from

a single click on a key on the keyboard, from the menu or from icons in the icon bar. The user is

given the possibility, on the basis of the 3D-view, to perform manual cleaning of areas with the

„Region Eraser‟ tool as well as of single points with the „Erase Tool‟ . It is possible to move

and rotate the data in the so-called „Navigation Mode‟ . In this mode it is furthermore possible

to change the scale – horizontally, by turning the mouse wheel as well as vertically, by

simultaneously pressing the CTRL-button and turning the mouse-wheel. Alternatively the

vertical scale can be altered by pressing one of the two icons .

By default only the accepted points are shown. However by pressing the icon, it is possible to

show deleted points. This includes points deleted in the present as well as in previous cleanings

sessions that have included the data in question.



Figure 68 3D Editor Settings

Finally, the 3D editor includes a window in which the settings can be defined and visualized (see

Figure 68 above). This comprises the (vertical) scale, the size (in pixels) of the data-points as

well as grid-specific settings and light settings. An important setting is associated with the „Tool

Toggling‟ option. It is possible to choose between „Cycling‟ and „Recent‟ options. The two

options are associated with the tools „Navigation Mode‟, „Erase Tool‟ and „Region Eraser‟.

„Cycling‟ will enable toggling between the three tools in sequence by pressing the space-bar.

„Recent‟ will toggle between the most recent of the „Erase Toll‟ and „Region Eraser‟ together

with „Navigation Mode‟. The user should in other words choose the „Recent‟ option if he/she has

a clear favourite eraser tool and the „Cycling‟ option if this is not the case.

Once the editing is finalized, close the window and choose the „Yes‟ option when prompted to

save the changes (see below). This will send the edited and cleaned data back to NM3 where a

re-indexing of the area in question will take place.

2.3.4.3 Flat Seabed Cleaning

„Flat Seabed Cleaning‟ will visualize a selection tool in the DTM-window identical to what is

used in connection with the „Point Edit 3D‟ described above. Upon selection, the window below

will appear, prompting the user to define whether or not to delete the points marked for deletion.

To support the decision, the number of points to be deleted is given. These points have been

defined automatically by NM3 based on a plane through the corners of the plane and a vertical

distance to this plane. The plane is defined as a least squares adjustment of the depth of the four

corners. The result of the least squares adjustment is the pitch and roll value of the plane that

fulfills the requirement that the sum of the squares of the corrections to the depth value of the

four corners is minimized.



2.3.4.4 Plane Cleaning with Polygon

Selection of the „Plane cleaning (pick polygon)‟ option from the Tools menu, will activate a tool

that is similar to the „Flat Seabed Cleaning‟ tool; however the plane is generated on the basis of a

user-defined polygon with a minimum of three corners. Each corner of this polygon is defined by

a simple mouse-click on the DTM. Once the polygon is defined, and the plane is determined

along the requirements described above, a deletion/selection tool is opened as shown below in

Figure 69, left. This shows, in the X-axis, the distance to the plane and in the Y-axis direction,

the distribution of points. As a guide, NM3 will give proposed maximum and minimum values

that are visualized with red vertical lines. These lines can be moved forth and back by manual

selection and movements with the mouse.

The user interface of the cleaning tool, when activated as part of the structured cleaning, is

identical to what is described above.

Figure 69 Plane Distance Selection tool (left) and DTM visualization

In order to assist on the selection, the X-axis is equipped with units and the number of points

received (from NM3) as well as the number of points deleted with the current settings of the

maximum/minimum lines is shown alphanumerically. The most important selection guide is

probably given in the DTM window where the consequence of moving the red vertical

maximum/minimum lines forth and back (left and right) can be monitored (see the red dots,

below right).



Upon completion the selections is accepted by pressing the „OK‟ button. This action will send

the cleaned data back to NM3 where a re-indexing of the area in question will take place.

2.3.5 Digitization Methods

The digitizing functionalities are invoked from the „Digitized Lines‟ entry under item „Toppings‟

in the „Project Tree‟ window as seen below in Figure 70. Alternatively, specifically for pipe-

associated tasks, the „Pipe Inspection‟ toolbar hosts functionalities for digitization of pipe related

objects.

Figure 70 Digitized Lines menu

2.3.5.1 New Digitized Line

Selection of this menu-item will generate a digitized line under the „Digitized Line‟ node in the

„Project Tree window‟. This line will immediately be equipped with a series of properties as seen

below in Figure 71, left. One of these is referring to the type of the line. The property for this item

can be chosen from a drop-down-list as shown in the figure.



Figure 71 New Digitized Line Property, prior to digitizing (left)

It is possible to choose the option „None‟, which is the default property, and then select from the

list at a later stage.

Once the properties have been defined, the cursor can be moved to the DTM window. Here it will

appear as a bull‟s eye with a white arrow down as shown below in Figure 72. Left-click will start

the digitizing process. For each new additional segment of the digitized line, perform a left-click.

To end the process, either double-click with the left button or press the „Esc‟ key on the keyboard.

The first action will add a new segment that ends in the position of the „double-click‟, whereas the

latter will end the digitized line at the position of the latest point.

To assist in the digitization, the relative range and bearing from the previous point in the line to the

present position of the cursor is visualised, as shown below in Figure 72.

Figure 72 Digitizing New line

2.3.5.1.1 Editing the Digitized Line

A series of tools are facilitated for the editing of the digitized line.



Moving an already digitized point is accomplished by clicking on one of the points and

subsequently moving it in the horizontal plane, by moving the lower ball and in the vertical plane,

by moving the top ball up and down.

To remove a misplaced point, click on the points in question. It will be marked yellow and can now

be deleted by pressing the „Delete‟ key on the keyboard.

To place a new point in between two points, double-click on the ball either before or after the new

point. It is now possible to place an unlimited number of points between this point and one of its

two neighbouring points (see Figure 73 below). Remember to stop adding points, either by double-

clicking or by pressing the „Esc‟ key on the keyboard, before the next original point is reached.

Figure 73 Adding Points to a Digitized Line

A digitized line can also be extended at both ends. This is accomplished by double-clicking on the

ball from where the extension should be made. The action to take is now identical to what is done

in connection with a normal digitization.



2.3.5.1.2 Creating Toppings from a Digitized Line

Figure 74 Digitized Line menu

As it appears from Figure 74 above, the menu that appears when right-clicking on a digitized line

in the „Project Tree‟ window, is quite comprehensive. Some of the items are more or less self-

explanatory. Of the remaining items, the primary items of interest, in the present context, are

however the „Exporting‟ and the „Create runline‟ menu-items.

Choosing the „Exporting‟ function, will open the „Export‟ dialogue, as seen below in Figure 75.

Figure 75 Export Dialogue (left) and drop-down items (right)

The drop-down-list for a digitized line based export is depicted to the right in the figure. It is in

other words possible, on the basis of a digitized line, to generate profiles (cross and long) as well as

track-information (without time), pipe-tracker information and a runline file (*.rln). The latter

export is identical to the „Create Runline‟ menu-item, that can be accessed directly from the

„Digitized Line‟ menu as shown above in Figure 74.



Further details on exporting is given below in chapter 2.3.7, Exporting.

2.3.5.2 New Digitized Pipeline

The „New Digitized Pipeline‟ functionality can be invoked from the „Pipe Inspection‟ toolbar or by

right-clicking in the „Toppings – Digitized Lines‟ entry of the „Project Tree‟ window and choosing

the menu item 'New digitized Pipeline' as shown below in Figure 76.

Figure 76 'New digitized Pipeline' menu option

Digitization of a pipeline is very useful in connection with exposed pipes. Prior to digitizing

however, the pipe diameter must be specified, either in the „Project Settings‟ as shown below in

Figure 77, left or in the „Properties‟ window to the right in the same figure. Note that in the latter

case, the diameter value is actually taken from the default settings specified in the „Pipe Settings‟

dialogue.

Figure 77 Pipe Settings in the Project settings dialogue (left) and in the „Properties‟ window (right)



Once the „New digitized pipeline‟ functionality has been selected, the cursor in the DTM window

will have changed its appearance. Click in an appropriate position with the left mouse-button to

start the digitizing process. For each new additional pipeline segment, perform a left-click. To end

the process, either double-click with the left button or press the „Esc‟ key on the keyboard. The

first action will add a new pipeline segment that ends in the position of the „double-click‟, whereas

the latter will end the digitized pipeline at the position of the latest point.


present position of the cursor is visualised (see below). The latter is of particular interest in

connection with digitizing pipe objects, since the angle between segments is used to flag for

bending violations. The default maximum allowable value is 3 degrees. This can be specified in the

„Pipe Settings‟ dialogue (see above in Figure 77), where the properties for the item „Acceptable

flexion of the pipe‟ can be specified.

To further assist in the digitization, the snap functionality can be switched to „True‟ (see above in

Figure 77, right). Also the „Video Lock‟ option can be set to „True‟. When the snap is turned to on,

a set of blue spheres will appear to the left and to the right of the cursor during the digitizing (see

Figure 78 below). The cross-track distance between the spheres is defined by the user in the „Snap

window width‟ option in the properties window (Figure 77, right) and the diameter of the spheres

is identical to the diameter of the pipe. The digitization will appear at the highest point (Top Of

Pipe) as long as the cursor is within the „Snap window width‟. The snap functionality is

particularly useful in connection with well-defined, relatively large exposed pipes (or cables),

whereas it is advised to turn the function off if the pipe is difficult to detect, based on the

bathymetric data/the DTM.

The video-lock functionality (see Figure 78 below) is used to force the video forward and/or

backward to the present position of the cursor and thereby of the digitized line, in order to supply

additional information for the determination of the whereabouts of the pipe. When activated, the

video lock functionality also works when the digitized line is being modified.



Figure 78 Using snap (see blue spheres) and video-lock

2.3.5.3 New Digitized Coverline

The „New Digitized Coverline‟ functionality can be invoked from the „Pipe Inspection‟ toolbar or

by right-clicking in the „Toppings – Digitized Lines‟ entry of the „Project Tree‟ window and

choosing the menu item 'New digitized cover line' as shown below in Figure 79.



Figure 79 'New digitized Coverline' menu option (left) and „Properties‟ window, right

In the „Properties‟ window to the right, it is possible to define the „Distance below cover line‟

option. This is the recommended line type to use if the pipe is buried but the pipetracker is exposed

or missing. When using cover lines to generate a pipe, the Quality is set to NA as seen below in

Figure 80.

Figure 80 Covered Pipeline with annotations



2.3.5.4 New Pipeline (Automatic Placement)

Figure 81 „New Pipe Line (Automatic Placement)' menu item

The „New Pipe Line (Automatic Placement)‟ is invoked by right-clicking in the „Toppings –

Digitized Lines‟ entry of the „Project Tree‟ window and choosing the menu item 'New digitized

cover line' as shown above in Figure 81. The dialogue visualised below in Figure 82 will appear.

Figure 82 Dialogue for autoplaced pipe

In this dialogue, it is possible to define the start and stop kp-value for the automatic placement. In

addition, the distance between automatically digitized points along the route must be defined (in

kilometres). Finally the search area (in meters), that specifies the maximum allowable

perpendicular distance from the runline for each digitized point, must be set. Once the digitized

pipe has been generated, it will act as a „New digitized Pipe‟. Note that the functionality only

works with a very well defined, relatively large, pipeline.



2.3.5.5 Recalculate KP for all lines

Figure 83 The 'Recalc KP for all lines' menu function

If a new runline has been loaded or if another runline has been made active, this functionality can

be used to recalculate kp-values.

2.3.5.6 Sort Lines

Figure 84 The 'Sort Lines' menu function

When digitizing pipe data, the digitized lines will be visualised in accordance with the sequence by

which the digitization took place. The „Sort Lines‟ functionality will organise the lines, under the

„Digitized Lines‟ entry, in ascending order, relative to the KP-values.

2.3.6 Pipe Functions

The pipe functionalities include operations that can be used, on the basis of the toppings loaded

and/or generated, to create and modify the pipe object. This includes Pipetracker functionalities as

well as functions directly associated with the pipe object.



2.3.6.1 Pipetracker Functionalities

As described in chapter 2.3.3.1, Pipe Information, NaviModel3 will generate a Kalman line along

the pipetracker path when pipetracker data is added to a project. As the name indicates, this

smoothed line is generated by a Kalman-filter and will be used to generate a new pipe added in

situations where there is no digitized line, provided the „Use Pipefilter‟ has been set to „True‟ (see

chapter 3.2.1.3, The Tools menu for details). If this is not the case, the pipetracker data will be used

directly to generate the pipe.

Apart from the pipetracker data, the Kalman filtered line is based on the pipetracker settings that

are defined in the „Pipe Tracker‟ tab of the Project settings window, as shown below in Figure 85.

Figure 85 Project Settings, Pipe Tracker tab

The default setting for the „Pipe Filter Flexibility‟ is 0.2 cm/m, which means that the Kalman pipe

is allowed to bend 2 mm per meter.

Figure 86 Consequence of varying the Pipe filter flexion value: at the top window: 10 cm/m, at the bottom: 0.2 cm/m



Figure 86 above visualises the consequence of varying the pipe filter value. In the top window, the

flexion is set to 10 cm/m. As a consequence, the blue Kalman line follows the pipetracker line

quite stringently. Using the default flexion value, on the other hand, as visualised at the bottom

window, will result in a Kalman line that is almost straight.

The „Pipe Fix Point‟ quality parameter is used to define the quality of pipe fixes. Pipe fixes are

points that can be made manually to assist the pipe tracker data. The functionality is invoked by

right-clicking on the „Pipetracker‟ entry under „Toppings‟ in the „Project Tree‟ window and

choosing the menu-item „New pipe fixes‟ as shown below in Figure 87.

Figure 87 'New Pipe Fixes' functionality

Pipe fixes can now be placed, with the mouse, in areas where the pipe tracker data must be

overruled. This is visualised below in Figure 88, where the pipe fixes are shown as white crosses.

Note that the default quality of the pipe fixes of 1 (cm) is used to overrule the pipetracker data, that

has been given the default quality of 2000 (cm). As a consequence, the Kalman line is relatively

close to the pipe fixes points whereas it follows the pipetracker data, in areas with no pipe fixes.

Figure 88 Pipe fixes to assist the pipetracker data

2.3.6.1.1 Validating/invalidating pipetracker data

Pipetracker data can be validated and invalidated by manual selection. The functionality is invoked

by right-clicking on the „Pipetracker‟ entry under „Toppings‟ in the „Project Tree‟ window and

choosing the appropriate menu-item, either „Invalidate Pipetracker Data‟ or „Invalidate Pipetracker

Data‟ as shown below in Figure 89.



Figure 89 'Invalidate Pipetracker Data' and 'Validate Pipetracker Data'

The tool will now appear on the DTM window as a circle, as shown in Figure 90 below right. The

radius of the circle will determine the number of pipetracker points to be made invalid. The radius

on the screen cannot be altered, however, by zooming in and out (mouse wheel) it is possible to

change the radius in absolute terms, and thereby to define the number of points that should be

invalidated.

Figure 90 Invalidate tool. Selection (left) and after invalidation (right)

The validation tool works in exactly the same ways as the invalidation tool. As can be seen below

in Figure 91, the validated points are given the quality parameter 17, irrespective of their former

quality parameter, to indicate that they are to be regarded „Auto Placed Points‟.



Figure 91 Validated points

2.3.6.2 Generating the Pipe

Once the digitization is finalised and the pipetracker data and thereby the Kalman line is

acceptable, the pipe can be generated. To do this, NaviModel3 will look for three different pieces

of information:

Digitized Pipe

Pipetracker data

Runline information

The digitized pipe information has first priority. In areas where this is found, it will be used to

generate the pipe object. If no digitized pipe information is available, NM3 will look for and use

pipetracker data and only in situations where no digitized pipe or pipetracker data is available, will

the runline information be used to generate the pipe.

Generation of the pipe is done either from the „Pipe Inspection‟ toolbar or by right-clicking in the

„Pipe‟ entry under „Toppings‟ in the „Project Tree‟ window as shown below in Figure 92, left.

Figure 92 'New Pipe' functionality, left and „Range Selection‟, right



When this is done, the „Range Selection‟ window in Figure 92, right will appear. The range can

either be entered manually or it can be determine through the use of the mouse. The latter is

activated by pressing the „Use mouse…‟ button. As a consequence the cursor will appear as a

bull‟s eye. The user can now choose the starting point and the end point of the pipe. When this is

accomplished, the pipe will appear in the DTM window, in the „Project Tree‟ window as well as in

the „KP-axis‟ window. Note that the diameter of the pipe will appear as specified in the „Pipe

Settings‟ tab of the „Project Settings‟ dialogue, as shown below in Figure 93. Details on this as well

as on the other tabs are found in chapter 2.2.1.3, The Tools menu, above.

Figure 93 Pipe Settings

When generated, the pipe will appear as shown below in Figure 94. Note the points of the pipe,

with a distance of 1 m. The distance is related to the distance between kp-values on the runline. In

some cases these might not be spaced exactly 1:1 as is the case in the example.



Figure 94 Pipe generated

Figure 95 Pipe Properties window

Once the pipe is generated, the properties can be modified. Many of the initial properties are

inherited from the „Project Settings‟ whereas other are default settings.

Cover Calculation:

o Fuzz factor: here the pipe coverage in cm before the pipe is tagged as covered can

be specified. Default value is 5 cm. A negative fuzz factor means that the pipe will

be marked as covered before it is actually fully covered



Cross profile export Options: These options are used when the pipe is used to export cross-

profile data

o Interval: specifies the horizontal distance between points in the cross profile

o Width: specifies the width of the cross profile

o Thickness: specifies the width along the runline where NM3 will collect data for

export of raw data in a cross profile (SITRAS (Raw))

o Points: here the number of points in the cross profile can be entered. Note that the

relationship between „Interval‟, „Width‟ and „Points‟ will always match (NM3 will

ensure this)

General:

o Visible: here the visibility of the pipe object can be toggled. This can also be

accomplished by right-clicking on the pipe item in the „Project Tree‟ window and

selecting „Hide‟ and „Show‟, respectively

o Diameter: this specifies the diameter of the pipe. The value is inherited from the

„Project Settings‟ dialogue

o Min KP, Max KP: these two values are inherited from the time that the pipe was

generated. They can be altered, however the change will not take effect until the

pipe is recalculated

Pipe Tracker alignment:

o Filtered Line: specifies whether or not the pipe should follow the pipetracker

(„False‟) or the Kalman line („True‟) is case of pipetracker data (and no digitized

data). The setting is inherited from the „Project Settings‟ dialogue

Runline Alignment:

o Below Seabed: If the pipe is aligned to the runline, this value specifies how far (in

meters) below the seabed, the pipe should be generated

Visualisation:

o Texture: specifies whether or not to apply texture mapping to the pipe object. If

applied, the functionality will look for a file called pipetexture.jpg in the

C:\EIVA\NaviModel 3\bin directory

o Points: can be toggled on/off

o Tube: can be toggled on/off

2.3.6.3 Modifying the Pipe

Once the pipe is generated, it can be modified. For this, NaviModel3 has a series of tools.

2.3.6.3.1 Visual control of the Pipe

The „Fly Mode‟ functionality can be used to perform a visual inspection of the pipe. To accomplish

this, press the icon in the „Standard Toolbar‟. The mode facilitates camera movements (of the

DTM window) relative to a selectable runline or pipe-related lines (pipe, flaglines, pipetracker or



digitized line). The speed of the movement can be altered by pressing the + - buttons that will

appear next to the icon when in „Fly Mode‟ .

When flying along the pipe, a variety of tools are available to check whether the pipe is placed

correctly or not.

Undesirable pipe bends can be located by altering the general pipe colour mode, to „Pipe_Flexion‟

(see Figure 96, left). This quality flagging uses the „Acceptable flexion of the pipe‟ value stated in

the „Pipe Settings‟ tab of the „Project Settings‟ (see Figure 96, left), and can be used to identify

bending violations on the pipe. The default value is 3 degrees.

Figure 96 Pipe Flexion Settings (left) and Pipe Color Mode set to „Pipe Flexion‟ (right)

Alternatively these bending violations can be visualised on the KP-axis window as shown below in

Figure 97. The violations are depicted on the DTM window at the bottom as red quality indicators

on the points of the pipe, whereas they are shown as red lines in the „Bending violation‟ line of the

„KP-axis‟ window at the top.



Figure 97 Pipe Flexion visualisation

Similarly the general pipe colour mode can be altered to „Burial_Status‟ as shown below in Figure

98. This can be used to check the „in‟ and „out‟ of burial of the pipe. The figure also shows the

„Exposed‟ and „Covered‟ status on the KP-axis window at the top. Note that the burial status can

only be visualised when the sideflags have been generated. More details on how to accomplish this

is found below in chapter 2.3.6.4, Generating the Side Flags.

Figure 98 Pipe Burial Visualisation

Often the transition between a pipetracker based pipe object and one that is based on digitized lines

will result in a bending violation. A seamless transition can be ensured in different ways: by

modifying the digitized line or by inserting pipe fixes on the pipetracker data.



2.3.6.3.2 Recalculate Pipe

When changes have been applied to the sources of a pipe, primarily the pipetracker data, the pipe

must be recalculated. This is accomplished by right-clicking on the Pipe Object in the „Project

Tree‟ window and selecting the menu-item „Recalculate‟ as shown below in Figure 99, left. A

window will appear, prompting the user to specify what to recalculate: Position and Flags, User

moved flags, Quality Status and Burial Status as visualised below in Figure 99, right.

Figure 99 Recalculate Pipe (left) and item for recalculation (right)

2.3.6.3.3 Use of Pipe Range



Figure 100 Select Pipe Range

Selected parts of the pipe object can be modified, by selecting a range of the pipe. This is

accomplished by right-clicking on the pipe object in question and selecting the menu-item „Select

Range‟ as shown above in Figure 100. When doing so, the cursor will change its appearance to a

bull‟s eye to indicate that a manual selection of the range is now facilitated. When the selection has

been accomplished, the pipe changes its appearance as shown below in Figure 101.

Figure 101 Selected range visualised

At the same time, the menu list associated with the pipe object has changes its appearance with a

series of additional items added as shown below in Figure 102.



Figure 102 Pipe Range menu items

It is in other words possible to modify the pipe within the selected range, for example apply status

and recalculate. Note that once the status has been changed, the pipe range resets itself and

recalculate, as well as other menu items, will then be associated with the entire pipe. To avoid this,

the user will have to re-select the pipe range prior to recalculating.

2.3.6.3.4 Set KP range

The „Set KP range‟ menu item, that also appears when right-clicking on a pipe object, will

facilitate a manual definition of the range of the pipe. When doing so, the cursor will change its

appearance to a bull‟s eye to indicate that a manual selection of the KP range is now facilitated.

When the selection has been accomplished, the pipe will be defined from the defined KP starting

and ending points as shown below in Figure 103.



Figure 103 Selection of KP range, prior (top) and after (bottom)

Note the KP-values given at the bottom of Figure 103 that indicates the starting and ending points

of the pipe.

2.3.6.4 Generating the Side Flags

Figure 104 Pipe project prior to generating flags

Sideflags can be generated automatically, by right-clicking on the pipe object in the „Project Tree‟

window and selecting the menu-item „Add sideflags‟. Based on the settings defined in the „Flag



Settings‟ tab of the „Project Settings‟ dialogue, as shown in Figure 105 below, the 5 flags will now

be placed automatically by NM3.

Figure 105 Flag settings



Figure 106 Pipe project after the side flags have been generated

2.3.6.4.1 Using the Flags

Once the flags have been generated, they will be visualised on the DTM window as shown in

Figure 106 above. The contents of the KP-axis window will also have changed, based on the flags.

The burial/exposed status will be shown in two different lines. This status is based on the cover on

top of the pipe, compared to the fuzz factor.

Also the „Possible Burial Error‟ is flagged in the KP-axis window. As shown below in Figure 107,

„Possible Burial Error‟ will be flagged when the pipe is buried less than what is specified for the

fuzz factor. In the present context the factor was set to 5 cm and the burial was only 1 cm. The pipe

will therefore be flagged as exposed -0.01 m. Chapter 2.3.6.2, Generating the Pipe gives more

details on the fuzz factor.



Figure 107 Possible Burial Error parameters (see red arrow)

Freespans will also be visualised in the KP-axis as well as on the DTM window. The latter appears

when hovering the cursor on one of the points of the pipe.

In Figure 108 below, a freespan is visualised. On the DTM window it appears that there is a

freespan of 0.31 m. This is the difference between the TOP and the Terrain z-value, corrected for

pipe diameter, which is 1.2 m in the present context, with terrain z being the average z-value of the

two adjacent flags (seabed left and seabed right of pipe).



Figure 108 Freespan

2.3.6.4.2 Digitizing Flags

Manual digitization of side-flags is facilitated in NaviModel3. Apart from the fact that digitizing

the pipe is really digitizing the TOP flag, all side flags can be digitized, which in effect means that

the automatically placed flags will be overruled in the area in question.

To accomplish this, right-click on the „Digitized Lines‟ entry under „Toppings‟ in the „Project

Tree‟ window, and choose the menu-item „New digitized line‟. Now change the „Type‟ of the line

to be digitized in the „Properties‟ window, as shown below in Figure 109. Note that all 5 flags as

well as the cover flag can be chosen.

Figure 109 Defining the Digitizing Line Type



Figure 110 below shows digitization of the left seabed outer flag. The digitisation is conducted in

order to move the automatically placed flags inside the DTM in an area where they were close to

the edge.

Figure 110 Digitizing the left seabed outer side flag line

2.3.6.4.3 Adding user defined Flags

Adding user defined flags is furthermore facilitated in NM3. Right-click on the pipe object in the

„Project Tree‟ window and choose the menu-item „Add user defined flags‟. The menu shown

below in Figure 111 will appear.

Figure 111 Defining user defined flags

It is possible to define a series of flags, including parameters like flag name, distance from pipe

(including sign) as well as unit (meters or factors to the radius of the pipe). In the present context,

two flags are defined. Pressing the „Create‟ button will make NM3 generate the flags as shown



below in Figure 112, where the two sets are generated between the inner and outer flags on both

sides of the pipe.

Figure 112 User defined sideflags generated

When highlighting a user defined side flag entry in the properties panel, it is furthermore possible

to change the properties as shown below in Figure 113. Of particular interest is the „Base Depth

on‟ where the default value is „Depth‟, which is the depth of the DTM in the particular location

(see item „Depth Description‟ = Survey Depth in Figure 113, left). Alternatively, the user can

specify to calculate the depth, based on the mean, maximum or minimum of one or more of the

sideflags in the particular profile.

Figure 113 Properties of user defined side flags, left and defining „Base depth on‟, right



Re-defining the „Base Depth on‟ entry as shown in Figure 113, right, makes a drop-down-list of the

various flag lines available for the definition. Once the definition is defined, the „Depth

Description‟ item will change to reflect the new definition as shown below in Figure 114.

Figure 114 Depth Description changed

2.3.6.4.4 Moving the flags

The side flags can also be modified and moved manually. This is done in the DTM window by use

of the mouse. Left-click on the flag without releasing the left mouse button. The flag will now have

a round sphere at the bottom as can be seen in Figure 115 below. The flag can now be moved in the

across-track direction and released whenever an acceptable placement has been accomplished.

Note in the figure, that, whereas the KP-value is constant, the z-value varies as the flag is moved.

Figure 115 Manual movement of sideflags: before movement (left) and during movement (right)



2.3.6.4.5 Export of Freespan and Burial status

Figure 116 Export Freespans/Burials

NM3 facilitates exporting of freespan and burial status for each pipe object in a project. Right-click

on a pipe object and choose menu-item „Export freespans/burials‟. The freespan burial status along

the pipe will be sent to Notepad as shown above in Figure 116.

The items shown are: KP range in absolute terms (minimum, maximum), Status (Covered,

Exposed or Freespan) and maximum value (in meters) within the range.

2.3.6.4.6 Pipe Listings

When choosing the menu item „Pipe Listings‟ from the pipe object in the „Project Tree‟ window,

the window visualised in Figure 117 below, will appear. The window supplies another way of

giving a fast overview of the pipe status along the pipe than the KP-axis window. As is the case

with the KP-axis window, however, the Pipe Listing window will scroll up and down in

accordance with the DTM view. It is also possible to double-click on a line in the Pipe Listing

window and thereby moving the DTM view (and the KP-axis window) in accordance.



Figure 117 Pipe Listings Window (bottom) and KP-axis window (top)

The items listed in the Pipe Listing window are associated with the points of the pipe (one line per

point). The items are (from left to right):

#: the point number

KP: the KP-value

Burial: the burial status (with colourcoded background, green for Covered, yellow for

Exposed and purple for Freespan)

Quality: the quality status (with colourcoded background, green for OK and red for NA)

TOP (m): the depth value of the TOP

MTR (m): mean trench (average of Left and Right Seabed Inner)

Source: displays the source of the pipe (pipetracker, digitized pipe, runline) (with

colourcoded background, green for digitized pipe, purple for pipetracker and red for runline)

Bend: the bend of the pipe in degrees (with colourcoded background, green for values less

than limit and red when limit is exceeded)

E (m): Easting coordinate



N (M): Northing coordinate

MSBL (m): Mean Seabed Left depth value (Left Seabed Outer)

MSBR (m): Mean Seabed Right depth value(Right Seabed Outer)

BOTL (m): Bottom Of Trench Left depth value (Left Seabed Inner)

BOTR (m): Bottom Of Trench Right depth value (Right Seabed Inner)

Burial defined: the source of the burial definition (Flags or User)

2.3.7 Exporting

Exporting from NaviModel3 involves generation of data that can be used for further processing,

typically in NaviPlot. Exporting can be associated with different toppings:

a runline object

a pipe object (or a digitized line object)

a displayline object

a chart or a chart definition series

Whereas exporting from the two first topping types utilize the „Export‟ function, the two latter

employ the „Area Export‟ function.

2.3.7.1 The ‘Export’ functionality

The „Export‟ function can be invoked by right-clicking on a runline object, on a pipe object or on a

digitized line object in the „Toppings‟ entry of the „Project Tree‟ window and choosing the

„Export‟ menu-item on the menu that will appear as shown below in Figure 118 for a runline based

export.

Figure 118 Invoking the „Export‟ dialogue (from a runline object)

Either way however, the „Export‟ dialogue that now appears will look as shown below in Figure

119.



Figure 119 'Export' dialogue

The export-formats available will however depend heavily on the object in question. The drop-

down-list for a pipe object based export is depicted below in Figure 120, left, whereas it would

appear as shown below right for a runline based export.

Figure 120 Formats available in 'Export' dialogue - based on pipe (left) and on runline (right)

The formats can be selected automatically from the drop-down lists. In case a format requires some

special settings, two arrows (right and left) will appear to the right in the dialogue window. When

pressing the arrow-right, the items with options that can be altered will appear, whereas the options

can be hidden again by pressing the arrow-left as it appears in Figure 121 below.

Figure 121 'Export' dialogue with options exploded

2.3.7.1.1 Exporting Pipe Related Information

Whereas exporting from a runline is more or less self-explanatory, the exporting associated with

a pipe object requires some explanation, particularly considering the context in which this is

written. The different formats are given in the sequence they appear in the drop-down-list

together with relevant comments, if any.



Figure 122 The 'Five point cross profile' format

This format export to n RIS flag profiles. The distance between profiles is depending on the flag

placement. Details on the format are given on the EIVA Training and Documentation Site:

http://download.eiva.dk/online-training/NaviEdit%20Help/Exporters/RIS-format.pdf

Figure 123 The „Cross Profile SITRAS (RAW)' format

The Sitras formats are Statoils pipe associated formats (Sitras = „Statoils Inspeksjons og

Tilstands Rapporterings System for rørledninger‟) (Norwegian for „Statoils Inspection and

Condition Reporting System for Pipelines‟). Documentation on the Sitras format(s) are found on

the EIVA Training and Documentation Site in:

http://download.eiva.dk/online-training/NaviEdit%20Help/Exporters/SITRAS%20formats.pdf

Figure 124 The „Cross Profile SITRAS (DTM)' format

Same as above.

Figure 125 The „Cross Profile SITRAS (Flag)' format

The files containing the 5 point edited cross profile records shall be named ooYYnnnn.C5P. The

http://download.eiva.dk/online-training/NaviEdit%20Help/Exporters/RIS-format.pdf




file can contain one or more records. Each 5 points cross profile record shall be built up as

specified on the EIVA Training and Documentation Site in:


Figure 126 The „Long Profile ASCII' format

The *.lpa format is EIVAs proprietary format for longitudinal profiles. The format is supported

in NaviPlot for further mapping and documentation.

Figure 127 The „Cross Profile ASCII‟ format

The *.xpa format is EIVAs proprietary format for cross profiles. The format is supported in

NaviPlot for further mapping and documentation.

Figure 128 The „VisualWorks Cross Profile (NaviEdit)' format

This format will output a cross profile that is supported by the VisualWorks software.

Figure 129 The „VisualWorks Cross Profile (SeaMap)' format




Figure 130 The „Cross Profile‟ format

The *.gcp format is another EIVA proprietary format for cross profiles. This particular export is

not flag dependent. The format is supported in NaviPlot for further mapping and documentation.

Figure 131 The „Cross Profile - Pipelock‟ format

Same as above, including pipelocked information.

Figure 132 The „Video Index‟ format

Figure 133 The „Navigation and depth record‟ format

Figure 134 The „Long Profile (Raw Points)‟ format

The *.lpa format is EIVAs proprietary format for longitudinal profiles (see above). This instance



exports the raw observations in the profile. The format is supported in NaviPlot for further

mapping and documentation.

Figure 135 The „Bluestream RAW data' format

Figure 136 The „Bluestream DTM data‟ format

Figure 137 The „VisualWorks Cross-Profile‟ format

This format will output a cross profile that is supported by the VisualWorks software.

Figure 138 The „Template_Test‟ format

2.3.7.1.2 Generating new template

It is possible to generate a new generic exporting format, by using the „New Template‟ button as

shown in Figure 121 above. When doing so, the empty window shown below in Figure 139 will

appear.



Figure 139 Export Template Generator window

The window has a series of settings that must be defined for the template to work properly, such

as:

Item:

o Can be selected from a comprehensive drop down list

o Format of item can be defined among a series of predefined formats (press the

„Format‟ text for a list of definitions

o „Add‟ – pressing this button will add the item to the list

o Clicking on the headline of an item will delete it from the list

Column separator. The item desired can be entered manually from the keyboard

Row separator. The item desired can be entered manually from the keyboard

Header Editor. Pressing this button will open the window below in which it is possible to

define a header from three different selections: 1) No header, 2) NaviModel Header and 3)

User Defined header. In the latter case, a series of predefined fields can be selected from a

drop-down-list

Format name. Entered manually from the keyboard

Extension. Entered manually from the keyboard

„Save Template‟ will save the template. This action will make it available from the drop-

down format list in subsequent sessions



Figure 140 Template (left) and available in 'Export' dialogue (right)

2.3.7.1.3 Generating new Batch

The „Export‟ function also has a batch exporting functionality built-in. This is invoked by using

the „New Batch‟ button as shown in Figure 121 above. When doing so, the empty window shown

below in Figure 141 will appear.

Figure 141 Batch Exporting window, empty (left) and with a new batch defined (right)

A variety of actions can now be defined by adding from the drop-down list. This list is identical to

the drop-down format list available in the „Export‟ dialogue. So by choosing from the list and by

pressing the „Add‟ button, a list of exports can be defined. By giving the Batch job an appropriate

name and by subsequently pressing the „Create‟ button, the job will be made available for future

exports from the drop-down format list in the „Export‟ dialogue as shown below in Figure 142.

Figure 142 Batch Export available in 'Export' dialogue



2.3.7.2 The ‘Area Export’ functionality

The dialogue for the topping types (displayline and chart) is almost identical with the difference

being that in connection with a chart-based export, the user has to define the cell size in the

properties for the chart, whereas this is done as part of the dialogue when exporting from a

displayline object.

The „Area Export‟ functionality in invoked by right-clicking on the relevant object (displayline file

or chart (series)) in the „Project Tree‟ and choosing the menu-item „Export…‟ as visualised below

in Figure 143, left. This action will open the „Area Export‟ dialogue, shown below in Figure 143,

right. Since the export in the example takes place relative to a displayline object, the user will

however prior to that be prompted for a cell-size for the export (see below).

Figure 143 Export menu-item (left) and Export Dialogue, General tab (right)

The „Area Export‟ dialogue has a series of tabs that are active if they have been selected in the

initial „General‟ tab. In Figure 143, right all tabs have been selected. Consequently all associated

tabs have been marked active with a green bubble. Otherwise the un-selected tabs would have been

indicated with a red bubble.



Figure 144 „Area Export‟ Dialogue, Image tab (left) and Grid tab (right)

In the Image tab in Figure 144 above left a series of items regarding the exporting of the

georeferenced bitmap can be defined:

name of file to be created

the bitmap type is always png

the terrain color can either be based on the rainbow palette or it can be based on the ramp

color specified

Light settings can be enabled/disabled with the settings specified (including settings for

shininess brightness and shade)

The Grid tab in Figure 144 above right facilitates the definition of the filename of the grid-file to be

exported. Furthermore the direction of the vertical axis can be flipped („Flip Z-direction‟). The

output will be based on the active DTM. The output will consequently be based on the model type

selected and on the cell size.



Figure 145 „Area Export‟ Dialogue, Soundings tab (left) and Contours tab (right)

The Soundings tab in Figure 145 above left facilitates the definition of the filename of the

soundings information to be exported to an ASCII file. The output will be the raw cleaned

observations available in the project.

In the Contours tab in Figure 145, above right, a series of items regarding the exporting of the

Contours can be defined:

maximum and minimum contour interval

number of iterations („Smooth‟). The more iterations, the smoother the contour

minimum contour length („Remove small‟) defines the maximum allowable length of any

contour line

in range interval, a maximum minimum range can be defined

Figure 146 Export Dialogue, Bathy Plot tab (left) and Project Settings, Misc Settings tab (right)



Finally, in the Bathy Plot tab in Figure 146 above left some items regarding the exporting of the

Bathy Plot can be defined:

Name of the ASCII file to receive the Bathy Plot information

Grid Settings:

o direction of grid for export

o interval in X-axis direction between points to be exported

o interval in Y-axis direction between points to be exported

Point Settings:

o Model Type for the export

o Include minimum and maximum

o Use raw points (enabled). If disabled: make DTM-based output. When raw points

are used, a search circle with the radius specified is used to find the values

o Grid the output. If „Enabled‟, the output will be moved to the position of the cells.

Otherwise the actual position of the points will be maintained in the output

The export files will, by default, be located in the position specified in the „Misc. Settings‟ tab of

the Project settings dialogue under the „Export path‟ option. The dialogue is invoked with the

menu-item „Tools – Project Settings‟.

2.3.7.3 Special Function for Displayline Export

A special case has been introduced for the export relative to a displayline object. This

functionality is described in detail in connection with the Bathymetric Postprocessing Tutorial,

that can be found in the dedicated NaviModel3 training site:





3. STEP-BY-STEP TUTORIAL, PIPE INSPECTION IN NAVIMODEL3

The purpose of the present Step-by-step Pipeline Inspection Processing Tutorial is to introduce the

various tools involved when carrying out a typical Pipeline Inspection Processing session with the

EIVA Hydrographic Software Suite, in a logical sequence.

In addition to the previous contents of the present tutorial, the step-by-step part will also include

aspects associated with eventing and it will involve video integration. Though considered

indispensable parts of a Pipeline Inspection Processing task, both features will only be dealt with

when considered essential for the enhancement of the understanding of how the making of the pipe

object is conducted i.e. how they can be supporting the applicable decision making. Further details

on the subject of eventing and video integration can be found in the dedicated manuals in the EIVA

Training & Documentation Site http://download.eiva.dk/online-training. Relevant details regarding

how to generate a DTM on the basis on bathymetric data as well as aspects associated with the

cleaning of such a model, can also be found on this site.

3.1 Preparing NaviModel3 for the Pipe Job

When preparing for a pipeline inspection session, the first thing to do is to start NaviModel3. At

start-up, NM3 will appear as shown below in Figure 147.

http://download.eiva.dk/online-training



Figure 147 NaviModel3 at start up

3.1.1 Loading and configuring the DTM

All data required for the pipeline inspection session must now be entered into NM3. First drag-and-

drop a cleaned digital terrain model into the DTM-window (see Figure 148). Now highlight the

DTM in the project tree and ensure that the colour mode „depth‟ has been chosen in the properties

panel and that the „geometry mode‟ (model type) has been set to minimum (see red arrows).



Figure 148 Step 1 DTM loaded

At this stage, the user should also choose the correct colour mode and light-settings. Colour mode

is defined by highlighting „Color modes – Depth‟ in the project tree. The properties panel will now

show the default settings as shown below in Figure 149. In the middle, the custom settings are

shown. Palettes can be chosen from a drop-down list, and from-step-to can be entered manually

from the keyboard. Fade is a boolean (true/false). When true, NM3 will fade seamlessly between

the colour-ranges as shown below in Figure 150. Alternatively the user could click on the

dedicated icon in the toolbar . A selection window (Figure 149, right) will appear that will enable

the user to select the palette directly.

Figure 149 Defining colour mode – default (left) and custom (middle) and the „Pick Palette‟ window (right)



Figure 150 Colour mode defined

The light setup is defined from menu-item „View – Light setup‟ (or from the dedicated icon in the

toolbar ). When activated, the window below in Figure 151 will appear, enabling the user to

choose between a number of predefined settings or to define his own settings. Note that the settings

in the figure are associated with the default values.

Figure 151 Light setup

3.1.2 Loading and configuring the Toppings

Next drag-and drop the various toppings onto the DTM-Window. In the present context toppings

are: runline, pipe tracker data, track for the ROV and video data. The runline will appear as a green

line, whereas the ROV-track associated with the video-information will be visualised as a yellow



line, as can be seen in Figure 152 below. When entering 3D-models, the user is prompted whether

or not the model should be placed at a fixed position in the mode (see Figure 153). Answer „No‟ to

this.

Figure 152 Toppings loaded

Figure 153 3D-model prompt

Now the video-windows must be opened. This is done by choosing the menu item „View – Video –

Open all video windows‟. Then move the camera position to an appropriate position on the DTM

and press the „Bring Video Here‟ icon . This will open the video in the actual position – this is

visualised below in Figure 155. Note that at this stage, an empty event window will open at the

bottom far right of NM3. Also note that if the video windows are not opened prior to pressing the

„Bring Video Here‟ icon, the prompt shown below will appear, urging the user to open the video

windows.



Figure 154 Video window prompt

Figure 155 Video windows opened

The actual video position will be visualised, in the DTM-window, as a sphere with beams

underneath (see the red arrow). Note also that the videos are fixed in time at this stage, as indicated

by the video toolbar ( ). Pressing the -button, will cause the video to start advancing,

whereas the - and the - buttons will make the video step back and forth, respectively.

To attach a 3DS model to the video position, highlight the „Cursor‟ item in the Project Tree

Window and choose „Attach…‟ the appropriate 3DS-model here, as shown below in Figure 156.



Figure 156 Attach 3DS-model

Figure 157 NM3 with 3DS-model



The next thing to do is to load the events that were generated online. These might have been re-

calculated with respect to the modifications performed in NaviEdit. To import the events, choose

menu item „File – Import…‟. This will open the window and the window to the left in Figure 158

will appear. Choose „Event Collection‟ in the panel to the left, choose appropriate format in the

middle column (NaviEvent in the present context) and do one of the following: a) browse to select

the file to import or b) drag-and-drop a file (or a folder that contains a file) to import. The path will

appear in the field at the top of the form. Finally press the „Import‟ button to activate the import in

accordance with the settings.

Note that if an appropriate template does not already exist, the user will have to generate one along

the guidelines described in chapter 2.2.1.1, The „File‟ menu, above.

Figure 158 ASCII import from - default (left) and with event collection selected (right)

Now the KP-axis window should be opened. This is done from the menu-item „View – KP-axis‟.

At this point in the process the KP-window will include all the online events as well as the runline

(including range) and the video-track. Choose menu-item „Show‟ from the KP-window and choose

which events and other items to visualise, as shown below in Figure 159. Figure 160 Shows

NaviModel after the KP-axis window is activated.



Figure 159 Show selection from KP-axis

Figure 160 NM3 including KP-axis & Events

The final thing to do before actually starting to generate the pipe object is to load the pipetracker

topping. Prior to that, however, the pipe tracker settings must be specified (see Figure 161,

below). These settings are defined in accordance with what is specified in chapter 2.3.6.1,

Pipetracker Functionalities, above.



Figure 161 Pipetracker Settings in the „Project Settings‟

To load pipe tracker data, drag-and-drop the appropriate, edited pipetracker information (in the

*.pip format) onto the DTM window of NM3. Observe that, as a consequence, there will appear

a pipetracker entry under the toppings item in the „Project Tree‟ window and that there will

appear a new line in the KP-axis window as shown below in Figure 162.

Figure 162 Pipetracker and Kalman data in the KP-axis window

In the DTM window, the pipetracker information is visualised with a green line with points. That

is the pipetracker line with observations (points). The blue line, shown below in Figure 163,

right, represents the Kalman Line. If selected by the user, the Kalman line can be used to place

the pipe at a later stage of the process.



Figure 163 Pipe Tracker data loaded into NM3, 'Project Tree' window, left and DTM window together with the

Kalman Filtered line (right)

3.2 The Pipe Object

In general terms, determination of the pipe object involves modification of the pipe and of the

flags. This determination should involve the following, as a minimum:

Undesirable pipe bends/bending violations

Burial status (buried/exposed)

Freespans

Events versus pipe status

Video versus pipe status

Events versus Video

The three last items are only relevant in cases where events and video is available in support of

the pipe determination. However, if this is the case, it is highly recommended to use all

information available, in order to arrive at the best possible solution for the pipe as well as for the

events. The optimum pipe determination process is consequently one that, in an iterative process

and using all available information, also modifies the events achieved online and supplies these

with offline events. NM3 has comprehensive facilities for conducting offline eventing as well as

for editing of events. These are described in detail in the two dedicated manuals, „Online

Eventing Manual‟ and „Offline Eventing Manual‟ that can be found in the EIVA Training and

Documentation Site, http://download.eiva.dk/online-training/NaviPac%20-%20Tools.htm.

The pipe object will be generated, within NaviModel3, on the basis of a priority list that looks as

follows: 1) digitized pipeline 2) pipetracker data (or Kalman line) 3) runline. Consequently: only

when no digitized pipeline and no pipe tracker data is available, will the runline be used to place

http://download.eiva.dk/online-training/NaviPac%20-%20Tools.htm



the pipe and only when no digitized pipeline is available, will the pipetracker data be used for the

pipe.

At this stage, it must therefore be decided whether or not the pipetracker information is adequate

as basis of the pipe object. Alternatively the following can be conducted:

modification of the pipetracker data

digitization of the pipe object

3.2.1 Modification of the pipetracker data

To evaluate whether or not modification of the pipetracker data is required, start by making a fly-

through relative to the data. Click on the „Fly Mode‟ icon in the „NM3 Standard Toolbar‟ and

choose the pipetracker item in the drop-down menu that will appear. The speed of the movement

can be changed by pressing the + and –buttons next to the icon . Press the „Esc‟ button

(when the DTM window is active) to exit the mode.

On the basis of the fly-through, pipe-tracker data must now be edited. NM3 contains a series of

tools for that:

definition of „Pipe Filter Flexibility‟

choice of using pipe filter (yes/no)

validation/invalidation of pipetracker data

use of pipefixes

NaviModel3 will generate a Kalman line along the pipetracker path when pipetracker data is added

to a project. The smoothed line can be used to generate a new pipe added in situations where there

is no digitized line, provided the „Use Pipefilter‟ has been set to „True‟ (see above in Figure 164).

If this is not the case, the pipetracker data will be used directly to generate the pipe.

Figure 164 Project Settings – „Use pipefilter‟



Apart from the pipetracker data, the Kalman filtered line is based on the pipetracker settings that

are defined in the „Pipe Tracker‟ tab of the Project settings window, as shown above in Figure 161.

The default setting for the „Pipe Filter Flexibility‟ is 0.2 cm/m, which means that the Kalman pipe

is allowed to bend 2 mm per meter.

The „Pipe Fix Point‟ quality parameter is used to define the quality of pipe fixes. Pipe fixes are

points that can be made manually to assist and thereby to improve the pipe tracker data. Right-click

on the „Pipetracker‟ entry under „Toppings‟ in the „Project Tree‟ window and choose the menu-

item „New pipe fixes‟ as shown below in Figure 165.

Figure 165 'New Pipe Fixes' functionality

Pipe fixes can now be placed, with the mouse, in areas where the pipe tracker data must be

overruled. This is visualised below in Figure 166, where the pipe fixes are shown as white crosses.

Note that the Kalman line is close to the pipe fixes points and far from the pipetracker data.

Figure 166 Pipe fixes to assist the pipetracker data

Pipetracker data can furthermore be validated and invalidated by performing a manual selection.

Right-click on the „Pipetracker‟ entry under „Toppings‟ in the „Project Tree‟ window and choose

the appropriate menu-item, either „Invalidate Pipetracker Data‟ or „Invalidate Pipetracker Data‟ as

shown below in Figure 167.



Figure 167 'Invalidate Pipetracker Data' and 'Validate Pipetracker Data'

The tool will now appear on the DTM window as a circle (see Figure 168, below, right). The

radius of the circle will determine the number of pipetracker points to be made invalid. Click with

the left mouse button whenever an appropriate selection has been made.

Figure 168 Invalidate tool. Selection (left) and after invalidation (right)

The validation tool works in exactly the same ways as the invalidation tool. As can be seen below

in Figure 169, the validated points are given the quality parameter 17, irrespective of their former

quality parameter, to indicate that they are to be regarded „Auto Placed Points‟.



Figure 169 Validated points

3.2.2 Digitizing the pipe object

The pipe object must now be digitized in areas where the pipetracker data is missing or where it

has been deemed not adequate, even after the modification has taken place. The digitization tool

is used for defining the pipe location, and it will override all measured pipe tracker data. The

pipe will follow exactly along the digitized line. Consequently more points must be digitized in

curves than on straight sections.

NM3 has two functionalities designed for the digitization of the pipe object:

The „New Digitized Pipeline‟ functionality

The „New Digitized Cover (NA)‟ functionality

Prior to digitizing, the pipe diameter must however be specified, either in the „Project Settings‟ as

shown below in Figure 170, left or in the „Properties‟ window, as shown to the right in the same

figure.

Figure 170 Pipe Settings in the Project settings dialogue (left) and in the „Properties‟ window (right)



The „New Digitized Pipeline‟ functionality is invoked from the „Pipe Inspection‟ toolbar or by

right-clicking in the „Toppings – Digitized Lines‟ entry of the „Project Tree‟ window and choosing

the menu item 'New digitized Pipeline' as shown below in Figure 171.

Figure 171 'New digitized Pipeline' menu option

Once the „New digitized pipeline‟ functionality has been selected, the cursor in the DTM window

will have changed its appearance. Click in an appropriate position with the left mouse-button to

start the digitizing process. For each new additional pipeline segment, perform a left-click. To end

the process, either double-click with the left button or press the „Esc‟ key on the keyboard. The

first action will add a new pipeline segment that ends in the position of the „double-click‟, whereas

the latter will end the digitized pipeline at the position of the latest point.


present position of the cursor is visualised (see below). The bearing is of particular interest in

connection with digitizing pipe objects, since the angle between segments is used to flag for

bending violations. The default maximum allowable value is 3 degrees. This can be specified in the

„Pipe Settings‟ dialogue (see above in Figure 170), where the properties for the item „Acceptable

flexion of the pipe‟ can be specified.

To further assist in the digitization, the snap functionality can be switched to „True‟. Also the

„Video Lock‟ option can be set to „True‟. When the snap is turned to on, a set of blue spheres will

appear to the left and to the right of the cursor during the digitizing. The cross-track distance

between the spheres is defined by the user in the „Snap window width‟ option in the properties



window and the diameter of the spheres is identical to the diameter of the pipe. The digitization

will appear at the highest point (Top Of Pipe) as long as the cursor is within the „Snap window

width‟. The snap functionality is particularly useful in connection with well-defined, relatively

large exposed pipes (or cables), whereas it is advised to turn the function off if the pipe is difficult

to detect, based on the bathymetric data/the DTM.

The video-lock functionality is used to force the video forward and/or backward to the present

position of the cursor and thereby of the digitized line, in order to supply additional information for

the determination of the whereabouts of the pipe. When activated, the video lock functionality also

works when the digitized line is being modified.

Figure 172 Using snap (see blue spheres) and video-lock

The „New Digitized Coverline‟ is the recommended line type to use if the pipe is buried but the

pipetracker is exposed or missing. The functionality is invoked from the „Pipe Inspection‟ toolbar

or by right-clicking in the „Toppings – Digitized Lines‟ entry of the „Project Tree‟ window and

choosing the menu item 'New digitized cover line' as shown below in Figure 173.



Figure 173 'New digitized Coverline' menu option (left) and „Properties‟ window, right

In the „Properties‟ window to the right, it is possible to define the „Distance below cover line‟

option. When using cover lines to generate a pipe, the Quality is set to NA as seen below in Figure

174.

Figure 174 Covered Pipeline with annotations

Digitization of a pipeline can be particularly useful in connection with exposed pipes. In rock

dump and burial areas, it can sometimes be expedient to stop digitizing when the pipe goes into the

area and proceed with a new digitized line where the pipe comes out the other side. If the quality

of the pipetracker-data is poor, a cover-line should be digitized, otherwise the pipetracker

information can be used directly.

Also be aware that, in order to use the pipetracker in freespan area, the digitized line must be ended

prior to the freespan and the digitization process must be resumed again after the freespan.

3.2.2.1 Modifying the digitized pipe

A series of tools can be used to assist in the editing of the digitized pipe line as it appears from

Figure 175, where the digitizing help text visualised in the Log window is shown.



Figure 175 Digitizing Help in the Log window

Clicking on a digitized point will make the point appear as a vertical line with two spheres (or

balls), one at the top and one at the bottom, as can be seen below in Figure 176.

Figure 176 Digitized point with spheres

Moving an already digitized point is accomplished by clicking on one of the points and

subsequently moving it in the horizontal plane, by moving the lower ball and in the vertical plane,

by moving the top ball up and down.

To remove a misplaced point, click on the point in question. It will be marked yellow and can now

be deleted by pressing the „Delete‟ key on the keyboard.

To place a new point in between two points, double-click on the ball either before or after the new

point. It is now possible to place an unlimited number of points between this point and one of its

two neighbouring points (see Figure 177 below).



Figure 177 Adding Points to a Digitized Line

A digitized pipeline can also be extended at both ends. This is accomplished by double-clicking on

the ball from where the extension should be made. The action to take is now identical to what is

done in connection with a normal digitization.

Marking a digitized point and clicking the „Shift‟ and „Delete‟ buttons simultaneously on the

keyboard will finally split the digitized line into two lines.

3.2.3 Generating the Pipe object

Once it has been established, that the digitization of the pipe object supports the edited and revised

pipetracker information adequately, the pipe object must be generated.

Generation of the pipe is done either from the „Pipe Inspection‟ toolbar or by right-clicking in the

„Pipe‟ entry under „Toppings‟ in the „Project Tree‟ window as shown below in Figure 178, left.

Figure 178 'New Pipe' functionality, left and „Range Selection‟, right

When this is done, the „Range Selection‟ window in Figure 178, right will appear. The range can

either be entered manually or it can be determine through the use of the mouse. The latter is

activated by pressing the „Use mouse…‟ button. As a consequence the cursor will appear as a

bull‟s eye. The user can now choose the starting point and the ending point of the pipe. When this



is accomplished, the pipe will appear in the DTM window, in the „Project Tree‟ window as well as

in the „KP-axis‟ window. In the DTM window, the pipe will appear as shown below in Figure 179.

Figure 179 Pipe generated, with points spaced 1 m

3.2.4 Modifying the Pipe

NaviModel3 has a series of tools for modification and editing of the pipe object, such as:

Changing the properties of the Pipe

Visual control of the Pipe

Pipe Flexion flagging

Recalculation of the Pipe

Use of Pipe Ranges

Setting of KP Ranges



Figure 180 Pipe Properties window

When the pipe has been generated, the properties must first be checked and modified. Highlight the

pipe object under „Toppings‟ in the „Project Tree‟ and focus on the properties window as shown

above in Figure 180. Many of the initial properties are inherited from the „Project Settings‟

whereas other are default settings.

Cover Calculation:

o Fuzz factor: here the pipe coverage in cm before the pipe is tagged as covered can

be specified. Default value is 5 cm

Cross profile export Options: These options are used when the pipe is used to export cross-

profile data

o Interval: specifies the horizontal distance between points in the cross profile

o Width: specifies the width of the cross profile

o Thickness: width along the runline for export of raw data in a cross profile

o Points: number of points in the cross profile

General:

o Visible: visibility of the pipe object can be toggled here

o Diameter: this specifies the diameter of the pipe

o Min KP, Max KP: potential change will not take effect until the pipe is recalculated

Pipe Tracker alignment:

o Filtered Line: specifies whether or not the pipe should follow the pipetracker

Runline Alignment:

o Below Seabed: if pipe is aligned to the runline, distance below seabed is given here



Next, the „Fly Mode‟ functionality can once again be used to perform a visual inspection of the

pipe, now that it is generated. When flying along the pipe, a variety of tools are available to check

whether the pipe is placed correctly or not.

Undesirable pipe bends can be located by altering the general pipe colour mode, to „Pipe_Flexion‟

(see Figure 181, left). This quality flagging uses the „Acceptable flexion of the pipe‟ value stated in

the „Pipe Settings‟ tab of the „Project Settings‟ (see Figure 181, left), and can be used to identify

bending violations on the pipe. The default value is 3 degrees.

Figure 181 Pipe Flexion Settings (left) and Pipe Color Mode set to „Pipe Flexion‟ (right)

Alternatively these bending violations can be visualised on the KP-axis window as shown below in

Figure 182. The violations are depicted on the DTM window at the bottom as red quality indicators

on the points of the pipe, whereas they are shown as red lines in the „Bending violation‟ line of the

„KP-axis‟ window at the top.

Figure 182 Pipe Flexion visualisation



Similarly the general pipe colour mode can be altered to „Burial_Status‟ as shown below in Figure

183. This can be used to check the „in‟ and „out‟ of burial of the pipe. The figure also shows the

„Exposed‟ and „Covered‟ status on the KP-axis window at the top. Note that the burial status can

only be visualised when the sideflags have been generated (see chapter 3.3 for details on this

subject).

Figure 183 Pipe Burial Visualization

Often the transition between a pipetracker based pipe object and one that is based on digitized lines

will result in a bending violation. A seamless transition must be ensured at this stage. This can be

accomplished in different ways: by modifying the digitized line or by inserting pipe fixes on the

pipetracker data.

When changes have been applied to the sources of a pipe, primarily the pipetracker data, the pipe

must be recalculated. This is accomplished by right-clicking on the Pipe Object in the „Project

Tree‟ window and selecting the menu-item „Recalculate‟ as shown below in Figure 184, left. A

window will appear, prompting the user to specify what to recalculate: Position and Flags, User

moved flags, Quality Status and Burial Status as visualised below in Figure 184, right.



Figure 184 Recalculate Pipe (left) and item for recalculation (right)

Figure 185 Select Pipe Range



Selected parts of the pipe object can be modified, by selecting a range of the pipe. This is

accomplished by right-clicking on the pipe object in question and selecting the menu-item „Select

Range‟ as shown above in Figure 185. When doing so, the cursor will change its appearance to a

bull‟s eye to indicate that a manual selection of the range is now facilitated. When the selection has

been accomplished, the pipe changes its appearance as shown below in Figure 186.

Figure 186 Selected range visualised

At the same time, the menu list associated with the pipe object has changes its appearance with a

series of additional items added as shown below in Figure 187.

Figure 187 Pipe Range menu items



It is in other words possible to modify the pipe within the selected range, for example „Apply

status‟ and „Recalculate‟. Note that once the status has been changed, the pipe range resets itself

and recalculate, as well as other menu items, will then be associated with the entire pipe. To avoid

this, the user will have to re-select the pipe range prior to recalculating.

The „Set KP range‟ menu item, that also appears when right-clicking on a pipe object, will

facilitate a manual definition of the range of the pipe. When doing so, the cursor will change its

appearance to a bull‟s eye to indicate that a manual selection of the KP range is now facilitated.

When the selection has been accomplished, the pipe will be defined from the defined KP starting

and ending points as shown below in Figure 188.

Figure 188 Selection of KP range, prior (top) and after (bottom)

Note the KP-values given at the bottom of Figure 188 that indicates the starting and ending

points of the pipe.

3.3 The Sideflags

When the pipe object is acceptable, the sideflags must be generated. This is done by right-clicking

on the pipe object in the „Project Tree‟ window and selecting the menu-item „Add sideflags‟.

Based on the settings defined in the „Flag Settings‟ tab of the „Project Settings‟ dialogue, as shown

in Figure 189 below, the 5 flags will now be placed automatically by NM3.



Figure 189 Flag settings



Figure 190 Pipe project after the side flags have been generated

3.3.1 Using the Flags

Once the flags have been generated, they will be visualised on the DTM window as shown in

Figure 190 above. The contents of the KP-axis window will also have changed, based on the flags.

The burial/exposed status will be shown in two different lines – one for burial and one for exposed.

This status is based on the cover on top of the pipe (one of the flags), compared to the fuzz factor.

Also the „Possible Burial Error‟ is flagged in the KP-axis window. As shown below in Figure 191,

„Possible Burial Error‟ will be flagged when the pipe is buried less than what is specified for the

fuzz factor. In the example the factor has been set to 5 cm and the burial was only 1 cm. The pipe

will therefore be flagged as exposed -0.01 m.



Figure 191 Possible Burial Error parameters (see red arrow)

Freespans will also be visualised in the KP-axis as well as on the DTM window. The latter appears

when hovering the cursor on one of the points of the pipe.

In Figure 192 below, a freespan is visualised. On the DTM window it appears that there is a

freespan of 0.31 m. This is the difference between the TOP and the Terrain z-value, corrected for

pipe diameter, which is 1.2 m in the present context, with terrain z being the average z-value of the

two adjacent flags (seabed left and seabed right of pipe).



Figure 192 Freespan visualised in the DTM window

3.3.2 Modifying the Flags

Once the flags have been generated, they must be checked. The most efficient way of doing this, is

to make a fly-through in order to check for misplaced flags, obstructions and holes in the DTM,

resulting in missing flags.

Modification of the flags can be performed in two different ways:

manual digitization of the flags

moving the flags

Manual digitization of side-flags is facilitated in NaviModel3. Apart from the fact that digitizing

the pipe is really digitizing the TOP flag, all side flags can be digitized, which in effect means that

the automatically placed flags will be overruled in the area in question.

To accomplish this, right-click on the „Digitized Lines‟ entry under „Toppings‟ in the „Project

Tree‟ window, and choose the menu-item „New digitized line‟. Now change the „Type‟ of the line

to be digitized in the „Properties‟ window, as shown below in Figure 193. Note that all 5 flags as

well as the cover flag can be chosen.



Figure 193 Defining the Digitizing Line Type

Figure 194 below shows digitization of the left seabed outer flag. The digitisation is conducted in

order to move the automatically placed flags inside the DTM in an area where they were close to

the edge.

Figure 194 Digitizing the left seabed outer side flag line

The side flags can also be modified and moved manually. This is done in the DTM window by use

of the mouse. Left-click on the flag without releasing the left mouse button. The flag will now have

a round sphere at the bottom as can be seen in Figure 195 below. The flag can now be moved in the

across-track direction and released whenever an acceptable placement has been accomplished.

Note in the figure, that, whereas the KP-value is constant, the z-value varies as the flag is moved.



Figure 195 Manual movement of sideflags: before movement (left) and during movement (right)

3.3.3 Export of Freespan and Burial status

Figure 196 Export Freespans/Burials

NM3 facilitates exporting of freespan and burial status for each pipe object in a project. Right-click

on a pipe object and choose menu-item „Export freespans/burials‟. The freespan burial status along

the pipe will be sent to Notepad as shown above in Figure 196.

The items shown are: KP range in absolute terms (minimum, maximum), Status (Covered,

Exposed or Freespan) and maximum value (in meters) within the range.

3.3.4 Pipe Listings

When choosing the menu item „Pipe Listings‟ from the pipe object in the „Project Tree‟ window,

the window visualised in Figure 197 below, will appear. The window supplies another way of

giving a fast overview of the pipe status along the pipe than the KP-axis window. As is the case



with the KP-axis window, however, the Pipe Listing window will scroll up and down in

accordance with the DTM view. It is also possible to double-click on a line in the Pipe Listing

window and thereby moving the DTM view (and the KP-axis window) in accordance.

Figure 197 Pipe Listings Window (bottom) and KP-axis window (top)

The items listed in the Pipe Listing window are associated with the points of the pipe (one line per

point). The items are (from left to right):

#: the point number

KP: the KP-value

Burial: the burial status (with colourcoded background, green for Covered, yellow for

Exposed and purple for Freespan)

Quality: the quality status (with colourcoded background, green for OK and red for NA)

TOP (m): the depth value of the TOP

MTR (m): mean trench (average of Left and Right Seabed Inner)

Source: displays the source of the pipe (pipetracker, digitized pipe, runline) (with

colourcoded background, green for digitized pipe, purple for pipetracker and red for runline)



Bend: the bend of the pipe in degrees (with colourcoded background, green for values less

than limit and red when limit is exceeded)

E (m): Easting coordinate

N (M): Northing coordinate

MSBL (m): Mean Seabed Left depth value (Left Seabed Outer)

MSBR (m): Mean Seabed Right depth value(Right Seabed Outer)

BOTL (m): Bottom Of Trench Left depth value (Left Seabed Inner)

BOTR (m): Bottom Of Trench Right depth value (Right Seabed Inner)

Burial defined: the source of the burial definition (Flags or User)

3.4 Exporting from a Pipe Object for further processing

The various results that are to be used for further processing in NaviPlot and in connection with

other, project specific documentation, is now to be exported from NaviModel3. This is done by

right-clicking on the pipe object under „Toppings‟ in the „Project Tree‟ window and choosing the

menu-item „Export…‟. The export dialogue, shown below in Figure 198, left, will appear.

Figure 198 Export dialogue for a pipe object (left) and formats available - based on a pipe object (right)

The drop-down-list for a pipe object based export, that will appear when clicking on the arrow-

down in the „Save as type‟ field, is depicted above in Figure 198, right. From here the format to be

exported can be selected.

A typical pipe-based plot in NaviPlot would typically involve a longitudinal profile and a cross

profile. For these, the „Long Profile Ascii (*.lpa)‟ for the longitudinal profile and „Cross Profile

Ascii (*.xpa)‟ or „Cross profile (*.gcp)‟ for the cross profile would apply. However also the

„VisualWorks Cross-profile (*.csv)‟ format, associated with events, is supported in NaviPlot.

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