presentation on cad/cam lab of vi sem syllabus

CAD/CAM Lab

1/30/2013 Dr. Bhimsen Soragaon, IEM, JSSATE, B'lore-60

For VI Sem. IE & M

W. E. F 2012-13

(10IML67)

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Agenda..• Course details• Syllabus • List of exercises to be conducted• Suggested software tools / Scheme of exam.• CAD / CAE / CAM• Solid Modeling Exercises• FEA Exercises• Machining Exercises• Model Viva-voce questions1/30/2013 Dr. Bhimsen Soragaon, IEM, JSSATE, B'lore-60 3


COURSE DETAILS

SUB CODE 10IPL /IML 67 IA MARKS 25

No. of Lecture (Lab) Hrs./ Week

03 Exam Hours 03

Total No. of Lab Hrs. : 42 Exam Marks 50

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PART – AModelling of simple machine parts using Graphics Package. Studyof Finite Element Analysis Package - 1D, 2D, Structural problems;Evaluation of displacement (Strain) and Stress. Problems involvingBeams and Trusses.

PART – BModeling and Simulation of Machining process of simple machineparts using standard CAM packages.

Syllabus

Note: A minimum of 12 exercises are to be completed

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Table of ContentsSl / Expt. / Exercise No. Date Title of the Expt. / Exercise Remarks

Part - A

1 Solid Modelling Exercise No.1




5 Finite Element Analysis Exercise No. 1





Part - B

10 Simulation of Turning operations Exercise – 1



13 Simulation of Milling operations Exercise – 1



16 Model viva-voce questions

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Suggested Software Packages

Solid Works / Uni Graphics / Catia / Solid Edge / MASTER CAM or any other similar packages

ANSYS for FEA

Scheme of External Examination

ONE question from part - A 20 Marks ONE question from part - B 20 MarksViva -Voice: 10 MarksTotal: 50 Marks

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Scheme of Internal Examination

Conduction of the experiment / model preparation / Simulation (including record book)= 15 marks

Test = 10 marks

Total = 25 marks

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Design-Manufacturing Process(before computer era)

Sketch with pencils

Engineering Drawing with pencils

Manufacturing

An Idea..

An Idea conceived …

Hydraulic Machine ….ByLeonardo-da-vinci

Engineering Drawing-Assembly

1/30/2013 11Dr. Bhimsen Soragaon, IEM, JSSATE, B'lore-60

Manufacturing

1/30/2013 12Dr. Bhimsen Soragaon, IEM, JSSATE, B'lore-60

Now…. with computer

CAD (Solid Modeling)

Engineering Drawing

Manufacturing

CAA (Computer Aided Analysis)

CAM (Computer Aided

Manufacturing) /Direct

Manufacturing

http://en.wikipedia.org/wiki/Computer-aided_design

Computer-Aided Design

• Computer-aided design (CAD) is the use ofcomputer systems to assist in the creation,modification, analysis, or optimization of adesign. (Groover, M. P.)

• CAD is essentially based on a versatile andpowerful technique called computer graphics.(Involving creation and manipulation ofpictures on a display device with the aid of acomputer).

1/30/2013 Dr. Bhimsen Soragaon, IEM, JSSATE, B'lore-60 14

The conventional design & CAD process


Area of focus – PART A

Geometric Modeling• Computer compatible mathematical description

of the geometry of an object.• The image of the object can be displayed &

manipulated on a graphics terminal throughsignals from the CPU of the CAD system.

• When a command is given, the computerconverts it into a mathematical model, stores itin the computer data files, and display it as animage on the display device.


• A geometric model may be 2D, 2.5D, 3D and..• A geometric model may be a wire frame

model, a surface model or a solid model.• Wireframe models are represented by lines

(straight or curved).• Surface models help visualizing complex

surfaces such as automated NC pathgeneration. Material volume information isambiguous or hard to determine.


Geometric Modeling

3D Wireframe Models


3D Surface Models


3D Solid Models



3D Solid Models

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Creating Solid Model• Primitive creation• Boolean operations• Sweep operations• Surface operations• Engineering Feature-Based modeling• Parametric modeling


Prerequisites:• Engineering drawing / Machine drawing concepts• Basic computer operation knowledge.

Commercial CAD/CAE Tools

• AutoCAD• Solid edge• Solid works• CATIA (Computer Aided Three-dimensional

Interactive Application)• Unigraphics – NX series• ANSYS• NISA• Nastran


Modeling Software Used• Solid Edge V19 or V20

– Runs on Microsoft windows and provides solid part modelling, assembly modelling, and drafting functionality.

– Originally developed and released by Intelligraph in 1996.

– Purchased and developed further by UGS in 1998.– Presently, owned and modified by Siemens PLM

Software, AG.– Present version is Solid Edge ST5.


Engineering Analysis

• Mass property analysis.– A feature of CAD system which provides

properties of solid object being analysed, such asthe surface area, weight, volume, centre of gravityand moment of inertia.

• Finite element analysis.– The object under analysis is divided into large

number of finite elements which form aninterconnecting network of nodes.


Finite Element Analysis• The basic unknowns in an engineering problem may

be:– Displacements & stresses in solid mechanics,– Velocities in fluid mechanics,– Electric and magnetic potentials in electrical engineering,– Temperatures in heat flow problems,– ……………

• The finite element procedure reduces such unknownsto a finite number by dividing the solution region into alarge number of small parts called elements,connected by nodes or nodal points.

• Solution for unknowns is sought for these nodalpoints, based on the element properties.


FEA Software Used• ANSYS, Inc. is a US based company that has

developed this computer-aided engineering (CAE) application package.

• A comprehensive general-purpose finite element computer program that contains over 100,000 lines of code.

• Capable of solving, numerically, a wide variety of mechanical problems - static/dynamic, structural analysis (both linear and nonlinear), heat transfer, fluid problems, as well as acoustic and electromagnetic problems.


Some Analysis Models


General Procedure Used

• Preprocessing: (defining the problem)– Build model, define material properties, define

element and its properties, discretization.

• Processing or solution– Apply boundary conditions

• Postprocessing– Interpretation of results (texts, numbers, graphs,

pictures


Computer Aided Manufacturing• Since the age of the Industrial Revolution, the

manufacturing process has undergone manydramatic changes.

• The most important of these changes is theintroduction of Computer AidedManufacturing (CAM), a system of usingcomputer technology to assist themanufacturing process (plan, manage, andcontrol the operations of productionequipment).


Commercial CAM Packages


Product Company

VoluMill Celeritive

CimatronE Cimatron

Mastercam CNC Software/Mastercam

CATIA Dassault Systemes

PowerMILL, FeatureCAM Delcam

ESPRIT DP Technology

CAMWorks Geometric Technologies, Inc.

e-NC ERCII

GibbsCAM Gibbs and Associates

Machinist Kubotek Corporation

Edgecam, Alphacam Planit

SolidCAM SolidCAM

Software Tool Used

• CAPSturn and CAPSmill Software Tools,developed by CADEM Technologies Pvt. Ltd. forCNC lathe and milling machines respectively.

• Possess in-built CAD to define the part shape,tools and cutting parameters database,extensive set of machining operations, tool pathsimulation, and generic post-processor.


General Working Procedure



A CNC Machining Center

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Solid Modeling ExerciseGenerate the solid model of the following machine part, given its orthographic views, Using solid edge / solidworks / unigraphics / catia software tool.

Software used: Solid Edge V19 / V20

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Solid Modeling ExerciseGenerate the solid model of the following machine part, given its orthographic views, Using solid edge / solidworks / unigraphics / catia software tool.

Software used: Solid Edge V19 / V20

Procedure: 1. Open Solid Edge – Solid Part package. 2. In the graphics window, select an appropriate plane. 3. Draw the relevant 2-D view in that plane and use

Protrusion / Cut Protrusion / Hole / other editing commands. 4. Specify appropriate dimensions and generate the solid part. 5. Use other planes if necessary and repeat step 3 and 4 to

complete the model.

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Solid Edge Initial Screen

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Solid Edge Part Modeling Initial Screen

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Solid Edge Part Modeling – Sketch Mode

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Solid Edge Part Model

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FEA Exercise

Prerequisites:

1. Mechanics of Materials

2. Concepts of Finite Element Method

3. Exposure to a modeling package

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FEA ExercisePerform a finite-element (FE) analysis on a cantilever beam shown infigure below and calculate the deflection of the beam at the loadingpoint and the stress distribution in the beam.

Data given:Geometry: length l =90 mm; Material: mild steel having Young’s modulus E=210 GPa and Poisson’s ratio ν=0.3. Boundary conditions: The beam isclamped to a rigid wall at the left end and loaded at x =80mm by a pointload of P =100 N.

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FEA ExerciseObservations: Software used: ANSYS V13Element used - Quad 8 node 82 (PLANE82)

Procedure:1. Open ANSYS. In the window that is displayed, select ‘Structural’ preferences.

Change the ‘file name’ if required. 2. Define the material properties and element properties. 3. Build the geometric model of the part by using suitable geometric elements.4. Convert the model into FE model by meshing the geometric model.

(Steps 3 & 4 can be grouped into one by using ‘nodes’ and ‘elements’ while building the model).

5. Apply boundary conditions (constrain left end of FE model appropriately and apply the load on the node as shown in the figure).

6. Solve the problem by choosing ‘solution’ option. 7. Interpret the results and record.

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ANSYS Initial Screen

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(1) Utility Menu: The Utility Menu contains functions that are availablethroughout the ANSYS session, such as file controls, selections, graphiccontrols, and parameters.(2) Input Line: The Input Line shows program prompt messages andallows to type in commands directly.(3) Toolbar: The Toolbar contains push buttons that execute commonlyused ANSYS commands. More push buttons can be made available ifdesired.(4) Main Menu: The Main Menu contains the primary ANSYS functions,organized by pre-processor, solution, general postprocessor, and designoptimizer. It is from this menu that the vast majority of modellingcommands are issued.(5) Graphics Windows: The Graphics Window is where graphics areshown and graphical picking can be made. It is here where the model inits various stages of construction and the ensuing results from theanalysis can be viewed.

Sections in ANSYS Main Window

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Select the ‘structural’ preference

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Define material properties

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Define element & its attributes

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Define element & its attributes

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Build the model

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Discretizing the model

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Discretized the model – nodes displayed


Constraints and Loading

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Solution

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Postprocessing - Deflection

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Postprocessing - Deflection

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Postprocessing – Stresses (Bending)

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Postprocessing – Reaction forces

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Machining Exercise - Prerequisites

• Machine tool details• Cutting tool details• Process planning• Work piece material• Cutting parameters• Part programming basics



Machining Exercise – Initial screenThe image cannot be displayed. Your computer may not have enough memory to open the image, or the image may have been corrupted. Restart your computer, and then open the file again. If the red x still appears, you may have to delete the image and then insert it again.


Machining Exercise – Part & Blank defined


Machining Exercise - Part & Blank defined


Machining Exercise – Tool path simulation


Machining Exercise – NC Code generation


Machining Exercise – Cycle time data

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presentation on cad/cam lab of vi sem syllabus

Documents

bhimsen soragaon

solid modelling exercise

d solid models

exercise remarks

computer graphics

solid edge v19

d surface models

mathematical model