Download - Wood Carving Simulator
Haptic Enabled Virtual Wood Carving
INDEX
1. Organizational Overview........................................................................................................2
2. Profile of the Problem..............................................................................................................5
3. Existing system.........................................................................................................................7
4. Problem Analysis.....................................................................................................................8
4.1 Product Definition...............................................................................................................84.3 Product Plan.......................................................................................................................10
5. Software Requirment Specification(SRS)............................................................................11
6. Software Design Document(SDD)........................................................................................26
7. Project Legacy........................................................................................................................35
9.1 Current Status of the project..............................................................................................359.2 Remaining Areas of Concern.............................................................................................35
8. User Manual...........................................................................................................................36
9. Abbreviations and Glossary..................................................................................................39
10. References...............................................................................................................................40
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Haptic Enabled Virtual Wood Carving
Organization Overview
Introduction
For most of India’s population, viable employment remains out of reach: 90 percent of
the work force is employed in informal, low-productivity jobs like daily wage labor, ad-
hoc plumbing, and brick laying.
This is not for lack of demand for skilled labor—as India’s economy booms, along with it
the need for skilled workers is high and rising. But vocational education and training
institutes have become a bottleneck: facing budget constraints and inadequate numbers of
trainers and materials, these traditional academic structures have been unable to keep up.
With its revolutionary application of haptic technology and multimedia, S.A.V.E is
opening the floodgates, demonstrating the means to provide vocational education on a
broader scale than ever seemed possible using traditional methods. And by targeting
individuals who have thus far been sidelined in India’s economic progress, S.A.V.E’s
work offers concrete proof that with proper application of modern technology, prosperity
and growth are increasingly achievable for all sectors of society.
Objective
Sakshat Amrita Vocational Education (s.a.v.e) aims to provide economically
marginalized populations with the opportunity to positively alter their employment
circumstances. Through its revolutionary approach to vocational education using cutting-
edge haptic technology and multimedia-enriched computerized training programs,
S.A.V.E is breaking down traditional logistical barriers to educating remote and
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Haptic Enabled Virtual Wood Carving
impoverished communities, and charting a course toward offering vocational education
on a scale never before possible.
S.A.V.E strives to:
Enhance the employability of the illiterate and semi-literate sections of society throughout
India.
Broaden the scope of existing vocational education and training institutes.
Accelerate the learning process via advanced technologies including haptics and
interactive multimedia tools.
Raise the standard of education, thus infusing the labor market with skilled and
productive workers/artisans who can earn a living wage and raise the standard of living in
their communities.
Scope
S.A.V.E harnesses the power of cutting-edge technology to extend vocational training
courses specifically to individuals and communities who—due to traditionally
insurmountable logistical and cultural barriers—have been long been left on the sidelines
of India’s economic progress. The revolutionary application of haptic technology and
multimedia renders limitless the potential reach of S.A.V.E. With multilingual support,
web-based user interface and low-cost, light-weight haptic technology replacing heavy-
duty tools and machinery, S.A.V.E is poised to shatter conventional limitations in
providing vocational training on a broad scale to some of India’s least-served populations.
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Haptic Enabled Virtual Wood Carving
Universalizing Education
S.A.V.E caters to a population that until now has been disproportionately handicapped in
their ability to enter into effective income-generating activities: illiterate, semi-literate
and individuals with limited education. S.A.V.E courses will be available in every major
Indian language and in English, guaranteeing that S.A.V.E can be effective nationwide.
Connectivity
With S.A.V.E courses accessible from anywhere where there is Internet or satellite
connectivity—desktop and laptop computers, standard mobile phones and smart-phones
—location will no longer be a barrier to vocational education. S.A.V.E courses can be
transmitted to remote locales, equipping these vulnerable communities with the skills and
means they need to survive and prosper in a changing world.
Low Cost Infrastructure
The unique application of haptic technology to vocational education will minimize the
need for materials and tools. Individuals will gain the experience of ‘working’ on
expensive equipment without risking damage, wear and tear. Additionally, the
accessibility of S.A.V.E further minimizes required infrastructure.
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Haptic Enabled Virtual Wood Carving
Profile of the problem
Introduction
The ancient Indian art and techniques of wood carving & carpentry are slowly dying. The
reasons are varied, from the long time it takes to become master the skills & techniques
involved to the lack of suitable markets. SAVE (Sakshat Amrita Vocational Education) at
the Amrita E-learning Labs intends to create a software and hardware system that will
capture the look and feel of working on real wood and then use this to record and teach
our traditional techniques of wood cutting and carving. My project will be the first step in
this direction by modeling a virtual wood that will emulate the look and feel of real wood
using advanced 3D graphics and haptics technologies. This project has inputs from the
Amrita Shilpa Kalakshetram in Trivandrum.
2.2 Objective and scope of project
The ancient Indian art of woodcarving is slowly dying because of the lack of students and
The opportunities are still attractive since handmade wood sculptures fetch tens of
thousands of rupees in the market. But due to the fact that schools that teach this ancient
art are few and masters of wood carving are hard to find these days, these traditions are
slowly being lost. Bringing haptics into this area serves two purposes:
Preserving a very important part of our culture by enabling the transmission of
techniques down the generations with the help of a Virtuo-Haptic immersive
environment.
Provide opportunities for the thousands of talented yet unemployed youth in India.
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Haptic Enabled Virtual Wood Carving
Provide hobbyists with the means to learn the art of woodcarving without
significant investment in wood, sculpting tools and tutors.
In parallel there is another team in SAVE that is working to make hardware that will give
the feel and feedback of real world wood sculpting tools. Presently I will be using a 3
degrees of freedom (movement and feedback) device, the Novint falcon to develop the
software. Although this device will not be suitable in the long run, it will be useful in
developing the haptics and graphics algorithms that will simulate the look and feel of real
wood.
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Haptic Enabled Virtual Wood Carving
Existing Similar Systems
No similar systems exist in this field at all. The most similar systems to haptic woodcarving
are the various bone drilling applications developed in Stanford University.
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Haptic Enabled Virtual Wood Carving
Problem Analysis
The ancient Indian art of woodcarving is slowly dying because of the lack of students
even though the opportunities are still attractive since handmade wood sculptures fetch
tens of thousands of rupees in the market. But due to the fact that schools that teach this
ancient art are few and masters of wood carving are hard to find these days, these
traditions are slowly being lost.
In parallel there is another team in SAVE that is working to make hardware that will give
the feel and feedback of real world wood sculpting tools. Presently I will be using a 3
degrees of freedom (movement and feedback) device, the Novint falcon to develop the
software. Although this device will not be suitable in the long run, it will be useful in
developing the haptics and graphics algorithms that will simulate the look and feel of real
wood.
4.1 Product definition
The virtual wood carving application is a part of the SAVE initiative (Sakshat Amrita
Vocational Education), an ongoing project of the Amrita E-learning Research Labs.
SAVE intends to virtually train millions of people in vocations that require trained skill
sets. Wood carving which requires hours of practice is an ideal application of haptics and
virtual reality
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Haptic Enabled Virtual Wood Carving
Importance and benefits:
The haptic wood carving application will be helpful in preserving our ancient
heritage by creating a skeleton application into which we can record the wisdom and
skills of the masters. There is also an employment aspect to it as woodcarving can be
mastered faster using a haptics application and highly skilled artisans can earn a lot of
money.
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Haptic Enabled Virtual Wood Carving
4.2 Project Plan
Modeling Virtual Wood
Sl. No Name of module Description of module Estimated work (days)
1 Algorithm 1 This is where the algorithm for isosurface extraction is determined
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2 Implementation 1 Implementing Marching Cubes to model virtual wood
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Total days: 50
Carving
Sl. No Name of module Description of module Estimated work (days)
1 Database design Localized Marching Cubes to for carving virtual wood
20
2 Database (sec: 1) Mesh deformation for carving
10
3 Database (sec: 2) Interactive viewing 104 Database (sec: 3) Pencil drawing 5
Total days: 45
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Haptic Enabled Virtual Wood Carving
System Requirements Specification
1. Introduction
1.1Purpose
The purpose of this document is to detail the requirement specifications for a Haptics
Enabled Virtual Wood Carving application. The ancient Indian art and techniques of
wood carving & carpentry are slowly dying. The reasons are varied, from the long time it
takes to become master the skills & techniques involved to the lack of suitable markets.
SAVE (Sakshat Amrita Vocational Education) at the Amrita E-learning Labs intends to
create a software and hardware system that will capture the look and feel of working on
real wood and then use this to record and teach our traditional techniques of wood cutting
and carving. My project will be the first step in this direction by modeling a virtual wood
that will emulate the look and feel of real wood using advanced 3D graphics and haptics
technologies. This project has inputs from the Amrita Shilpa Kalakshetram in
Trivandrum.
1.2Project Scope
The ancient Indian art of woodcarving is slowly dying because of the lack of students and
The opportunities are still attractive since handmade wood sculptures fetch tens of
thousands of rupees in the market. But due to the fact that schools that teach this ancient
art are few and masters of wood carving are hard to find these days, these traditions are
slowly being lost. Bringing haptics into this area serves two purposes:
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Haptic Enabled Virtual Wood Carving
Preserving a very important part of our culture by enabling the transmission of techniques
down the generations with the help of a Virtuo-Haptic immersive environment.
Provide opportunities for the thousands of talented yet unemployed youth in India.
Provide hobbyists with the means to learn the art of woodcarving without significant
investment in wood, sculpting tools and tutors.
In parallel there is another team in SAVE that is working to make hardware that will give
the feel and feedback of real world wood sculpting tools. Presently I will be using a 3
degrees of freedom (movement and feedback) device, the Novint falcon to develop the
software. Although this device will not be suitable in the long run, it will be useful in
developing the haptics and graphics algorithms that will simulate the look and feel of real
wood.
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Haptic Enabled Virtual Wood Carving
Overall Description
1.3Product Perspective
The virtual wood carving application is a part of the SAVE initiative (Sakshat Amrita
Vocational Education), an ongoing project of the Amrita E-learning Research Labs.
SAVE intends to virtually train millions of people in vocations that require trained skill
sets. Wood carving which requires hours of practice is an ideal application of haptics and
virtual reality
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Haptic Enabled Virtual Wood Carving
1.4Product Features
Models properties of actual wood as realistic as possible both visually and haptically.
Allows the student to feel the texture and shape of wood sculptures and wood pieces.
Provides basic wood carving lessons.
The software detects errors in the basic carving lessons and alerts the student.
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Haptic Enabled Virtual Wood Carving
1.5User Classes and Characteristics
Students
o Students new to the field of sculpting will use this software to learn the basics of the
trade.
o Since the tool is designed for the use of students of sculpting primarily, it is important
that I gauge their comfort with using computers.
Expert Instructors
o Experts in the field of wood carving will evaluate the software and give feedback which
will go onto making the software more effective.
o Of particular interest will be in comparing real world teaching techniques with virtual
ones.
SAVE team members
o Other developers on the SAVE team will also evaluate the software. They will be
interested in seeing how the software fits into the overall scheme of things at SAVE.
1.6Operating Environment
Hardware Environment
A system with minimum 2GB RAM and a multicore processor with speed >2 GHz
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Haptic Enabled Virtual Wood Carving
A medium or high end GPU for graphical processing.
A sound card.
A Three Degrees of freedom (3-DOF) haptics device like the Novint Falcon. 6 DOF
devices like the Sensable Phantom are preferred.
Software Environment
Windows Vista or Windows 7 as the OS.
CHAI3D Graphics/Haptics scenegraph library.
Novint Falcon drivers.
OpenAL and/or BASS audio libraries.
Visual Studio 2005 or 2008.
Virtual haptic device
1.7Design and Implementation Constraints
One particular constraint of this project is that a wood carving tool would need a 6 DOF
device. However the haptic device available for SAVE is the Novint Falcon which is a
3DOF device.
There is a need for a medium to high end graphics card onboard the computer since the
graphics in the application will be demanding.
1.8Assumptions and Dependencies
Assumptions:
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Accurate representation of an anisotropic material like wood will be possible through voxels and
the forces calculated using them.
The lack of a 6 DOF haptic device would not affect the usability of the software significantly. 6
DOF devices are under development at SAVE and commercial ones will also be procured. But
since their timeline exceeds that of my available project time,
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Haptic Enabled Virtual Wood Carving
2. System Features
2.1Generation of Wood voxels
3.1.1 Description and Priority
The virtual wood will be represented as voxels (volumetric data) with each voxel
representing a point in space with associated texture, stiffness and other haptic properties.
Unlike volumetric data available from MRI scans for haptic surgery applications, there
are currently no publicly available MRI or other volumetric data sets to use in the
application.
Therefore my software will either dynamically generate its own voxel data or allow the
user to manually input in voxel data.
Priority for this module is not very high at the early stages of application development.
Initially all voxels will have uniform properties with which the haptic & graphic
algorithms will be tested. This module can be developed at a later stage.
3.1.2 Stimulus/Response Sequences
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Haptic Enabled Virtual Wood Carving
2.2Graphic rendering of the virtual wood
3.2.1 Description and Priority
The wood volumetric data needs to be rendered by extracting surface voxel data into
isosurfaces that can be rendered as primitive triangles in OpenGL. I propose to use
Yarden Livnat and Charles Hansen’s method for isosurface extraction which is halfway
between CPU intensive ray tracing and GPU intensive Marching Cubes algorithm. For
graphics refresh rate to be maintained near 60 Hz it is important that the voxel access time
is constant or close to O(n) or lesser. The texture stored in each voxel will be queried to
display as corresponding colored triangles in OpenGL.
The priority of this module is very high since visual realism is important in a teaching
environment that places importance on visual inspection to judge the quality of the work.
3.2.2 Stimulus/Response Sequences
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Haptic Enabled Virtual Wood Carving
2.3Haptic rendering of wood and sculpting tool
3.2.1 Description and Priority
Haptic rendering is as important a critical activity as graphical rendering. It is important
to haptically capture the feel of carving into wood. Each voxel will have a haptic property
associated with it. Therefore the feedback force will be calculated from all the voxels
currently in contact with the sculpting tool. This done by calculating a negative force
depending on the vector of the chiseling tool, its incident force and the cumulative value
of the haptic texture property of all the voxels that the tool is touching (by taking an
average of all the friction parameters).
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Haptic Enabled Virtual Wood Carving
3.2.2 Stimulus/Response Sequences
2.4Introductory lessons to wood carving
3.2.1 Description and Priority
This module does not have very high priority value but nevertheless is intended to show
the utility of the whole application which will eventually be used as a tutor and one stop
place to learn everything about the Indian art of wood carving. This introductory part will
teach the student basic wood carving lessons like how to place the tool on the wood and
then perform some simple tasks like engraving a line, making pyramid shaped engravings
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Haptic Enabled Virtual Wood Carving
and some others with increasing complexity. This module will be completed only if the
time allows it.
3.2.2 Stimulus/Response Sequences
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Haptic Enabled Virtual Wood Carving
3. External Interface Requirements
3.1Software Interfaces
CHAI3D Library : The open source CHAI (Computer Haptics & Active Interfaces) library is a Visuo-
Haptic library created by researchers at Stanford University. It’s a scenegraph library in which we
can define haptic and graphic properties for each object. Its written in C++. Graphics in CHAI3D is
using OpenGL and direct use of OpenGL primitives is also possible offering more flexibility than
other visuo-haptic libraries like H3DAPI.
Novint Falcon Driver : This is the software component that talks with the Novint falcon haptic
game controller. All interaction with the device is through this driver. CHAI3D provides a layer of
abstraction over this for the convenience of programmers.
Nvidia CUDA : An optional component at this stage, this might be used for storing voxels and for
speeding up graphical rendering since CUDA allows programmers to directly use the parallel
computing resources of the GPU.
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Haptic Enabled Virtual Wood Carving
4. Other Nonfunctional Requirements
4.1Performance Requirements
5.1.1 Computational Requirements
There are two parallel threads running in this application. One takes care of graphical
rendering while the other takes care of haptic rendering. The graphical rendering thread runs at
60 Hz while the haptic rendering thread runs at 1000 Hz since these are the rates at which
humans feel that the graphical or haptic feedback is realistic. But whatever be done, the haptic
thread should never slow down. Therefore care must be maintained not to burden the haptic
thread with tasks that are computationally heavy.
5.1.2 Processing Power
The application requires a mid-range graphics card and a fast processor since the
graphics for the application needs to be as realistic as possible. The points described earlier
under “computational requirements” also make the case for larger processing power, stronger.
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Haptic Enabled Virtual Wood Carving
Appendix A: Glossary
Haptics : Haptic technology, or haptics, is a tactile feedback technology that takes
advantage of a user's sense of touch by applying forces, vibrations, and/or motions to the
user.
CUDA: is a parallel computing architecture developed by Nvidia.
Voxel : A voxel (volumetric pixel) is a volume element, representing a value on a regular
grid in three dimensional space.
OpenAL : It is a cross-platform 3D audio API appropriate for use with gaming
applications and many other types of audio applications.
Degrees of Freedom : are the set of independent displacements and/or rotations that
specify completely the displaced or deformed position and orientation of the body or
system.
GPU : It is a specialized processor that offloads 3D graphics rendering from the
microprocessor.
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Haptic Enabled Virtual Wood Carving
Software Design Specification
1. Introduction
1.1 Purpose
The purpose of this document is to detail the design specifications for a Haptics Enabled
Virtual Wood Carving application. The ancient Indian art and techniques of wood carving
& carpentry are slowly dying. The reasons are varied, from the long time it takes to
become master the skills & techniques involved to the lack of suitable markets. SAVE
(Sakshat Amrita Vocational Education) at the Amrita E-learning Labs intends to create a
software and hardware system that will capture the look and feel of working on real wood
and then use this to record and teach our traditional techniques of wood cutting and
carving. My project will be the first step in this direction by modeling a virtual wood that
will emulate the look and feel of real wood using advanced 3D graphics and haptics
technologies. This project has inputs from the Amrita Shilpa Kalakshetram in
Trivandrum.
1.2 Scope
The ancient Indian art of woodcarving is slowly dying because of the lack of students and
The opportunities are still attractive since handmade wood sculptures fetch tens of
thousands of rupees in the market. But due to the fact that schools that teach this ancient
art are few and masters of wood carving are hard to find these days, these traditions are
slowly being lost. Bringing haptics into this area serves two purposes:
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Haptic Enabled Virtual Wood Carving
Preserving a very important part of our culture by enabling the transmission of techniques
down the generations with the help of a Visuo-Haptic immersive environment.
Provide opportunities for the thousands of talented yet unemployed youth in India.
Provide hobbyists with the means to learn the art of woodcarving without significant
investment in wood, sculpting tools and tutors.
In parallel there is another team in SAVE that is working to make hardware that will give
the feel and feedback of real world wood sculpting tools. Presently I will be using a 3
degrees of freedom (movement and feedback) device, the Novint falcon to develop the
software. Although this device will not be suitable in the long run, it will be useful in
developing the haptics and graphics algorithms that will simulate the look and feel of real
wood.
1.3 Reference Material
The US Dept of Agriculture’s “Wood Handbook”
“Visuohaptic Simulation of Bone Surgery for Training and Evaluation” by Christopher
Sewell et al.
“Voxel-Based Interactive Haptic Simulation Of Dental Drilling” by Jun Wua et al.
“CHAI: An Open-Source Library for the Rapid Development of Haptic Scenes”by
Francois Conti et al.
2. SYSTEM OVERVIEW
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Haptic Enabled Virtual Wood Carving
The virtual wood carving application is a part of the SAVE initiative (Sakshat Amrita
Vocational Education), an ongoing project of the Amrita E-learning Research Labs.
SAVE intends to virtually train millions of people in vocations that require trained skill
sets. Wood carving which requires hours of practice is an ideal application of haptics and
virtual reality.
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Haptic Enabled Virtual Wood Carving
3. SYSTEM ARCHITECTURE
3.1 Architectural Design
This diagram shows the overall design of the software and how each of the modules are
connected.
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Haptic Enabled Virtual Wood Carving
3.2 Decomposition Description
Here we go into the functional association between the different components.
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Haptic Enabled Virtual Wood Carving
4. COMPONENT DESIGN
4.1 UML sequence diagram of the CHAI3D virtual sculpting program
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Haptic Enabled Virtual Wood Carving
4.2 UML Activity diagram describing the Marching Cubes isosurface generating algorithm
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Haptic Enabled Virtual Wood Carving
These are the 14 different cases used for generating isosurfaces in the Marching Cubes method
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Haptic Enabled Virtual Wood Carving
4.2 UML Activity diagram describing Haptic rendering for the sculpting tool
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Haptic Enabled Virtual Wood Carving
Project Legacy
9.1. Current Status of the project
The system is currently partially complete. Work still needs to be done on the
localized marching cubes approach. The mesh deformation technique used currently
will be adapted for haptic carpentry lessons which require lesser precision and skill
than wood carving.
9.2. Remaining Areas of concern
Adaptive isosurface generation algorithms need to be used to smooth out the edges
while carving.
Octree based in the GPU is another feature to explore. This would lead to wood with
resolutions that is a thousand times more detailed than at present.
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Haptic Enabled Virtual Wood Carving
User Manual
Screenshots
Volumetric Virtual Wood
Drawing on the Virtual Wood
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Haptic Enabled Virtual Wood Carving
Carving on the virtual wood using Mesh deformation
Carving using localized marching cubes algorithm
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Interactive Viewing
User options
Key ‘x’ – Close application
Key ‘r’ – Rotate virtual wood
Key ‘w’ – Wireframe show mode
Key ‘f’ – Fullscreen mode
Key ‘m’ – Use localized marching cubes
Key ‘p’ – Change tools (pencil to chisel and back)
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Haptic Enabled Virtual Wood Carving
Abbreviations & Glossary
Glossary
Haptics : Haptic technology, or haptics, is a tactile feedback technology that takes advantage
of a user's sense of touch by applying forces, vibrations, and/or motions to the user.
CUDA: is a parallel computing architecture developed by Nvidia.
Voxel : A voxel (volumetric pixel) is a volume element, representing a value on a regular grid
in three dimensional space.
OpenAL : It is a cross-platform 3D audio API appropriate for use with gaming applications
and many other types of audio applications.
Degrees of Freedom : are the set of independent displacements and/or rotations that specify
completely the displaced or deformed position and orientation of the body or system.
GPU : It is a specialized processor that offloads 3D graphics rendering from the
microprocessor.
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Haptic Enabled Virtual Wood Carving
References
The US Dept of Agriculture’s “Wood Handbook”
“Visuohaptic Simulation of Bone Surgery for Training and Evaluation” by
Christopher Sewell et al.
“Voxel-Based Interactive Haptic Simulation Of Dental Drilling” by Jun Wua et al.
“CHAI: An Open-Source Library for the Rapid Development of Haptic Scenes”by
Francois Conti et al.
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