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Sr. No.

Particulars

Page Number

1 Academic Calendar

2 Time Table (Consolidated)

3 Time Table (Individual)

4 Scheme

5 Syllabus

6 Lecture Plan

7 List of Books

8 Tutorial Sheets

9 Assignments

10 Assignment Grades

11 Question Papers

12 Lecture Notes

13 Attendance Record

FACULTY NAME

SIGNATURE

Course of Study and Scheme of Examination for Batch

starting from DEC-MAY 2018-19

B.E 6TH Semester

Teaching Scheme Credits Examination Marks

Total Marks L T P C

Theory Marks Practical Marks

ESE

(E)

PA (M) PA (V) PA

(I) PA ALA ESE OEP

3 0 2 5 70 20 10 20 10 20 150

SSYYLLLLAABBUUSS

UNIT-I

Introduction:

A typical product cycle, CAD tools for the design process of product cycle, CAD / CAM system evaluation

criteria, Input / Output devices; Graphics Displays: Refresh display, DVST, Raster display, pixel value and

lookup table, estimation of graphical memory, LCD, LED fundamentals. Concept of Coordinate Systems:

Working Coordinate System, Model Coordinate System, Screen Coordinate System. Line and Curve

generation algorithm: DDA, Bresenham’s algorithms. Graphics exchange standards and Database

management systems

.UNIT-II

Curves and Surfaces:

Parametric representation of lines: Locating a point on a line, parallel lines, perpendicular lines, distance of a

point, Intersection of lines. Parametric representation of circle, Ellipse, parabola and hyperbola. Synthetic

Curves: Concept of continuity, Cubic Spline: equation, properties and blending. Bezier Curve: equations,

properties; Properties and advantages of B-Splines and NURBS. Various types of surfaces along with their

typical applications

UNIT-III

Mathematical representation of solids:

Geometry and Topology, Comparison of wireframe, surface and solid models, Properties of solid model,

properties of representation schemes, Concept of Half-spaces, Boolean operations. Schemes: B-rep, CSG,

Sweep representation, ASM, Primitive instancing, Cell Decomposition and Octree encoding

UNIT-IV

Geometric Transformations:

Homogeneous representation; Translation, Scaling, Reflection, Rotation, Shearing in 2D and 3D;

Orthographic and perspective projections. Window to View-port transformation.and shaping of glass,

Composite materials, Processing of metal matrix and ceramic matrix composites, Processing

semiconductors.

Semester Course Title Course Code Theory Paper

L T P

MECHANICAL COMPUTER AIDED

DESIGN 2161903 3 0 2

Max.Marks:70

Min. Marks:23

Duration :2:30 hours

UNIT – V

Finite Element Analysis:

Review of stress-strain relation and generalized Hooke's Law, Plane stress and Plane strain conditions;

Concept of Total Potential Energy; Basic procedure for solving a problem using Finite Element Analysis. 1-

D Analysis: Concept of Shape function and natural coordinates, strain - displacement matrix, derivation of

stiffness matrix for structural problems, properties of stiffness matrix.

1-D structural problems with elimination and penalty approaches, 1-D thermal and fluid problems. Trusses

and Beams: Formulation of stiffness matrix, simple truss problems to find displacement, reaction and

stresses in truss members.

Structural analysis using Euler-Bernoulli beam element. Higher Order Element: CST element stiffness

matrix formulation, shape functions and applications of Quad and ax symmetric elements.

LECTURE PLAN

Lect Topics to be covered Teaching hours

1. A typical product cycle, CAD tools for the design process of product cycle 1

2 CAD / CAM system evaluation criteria, Input / Output devices 1

3 Graphics Displays: Refresh display, DVST, Raster display, pixel value and

lookup table 1

4

Estimation of graphical memory, LCD, LED fundamentals. Concept of

Coordinate Systems: Working Coordinate System, Model Coordinate

System, Screen Coordinate System.

1

5 Line and Curve generation algorithm: DDA, Bresenham’s algorithms 1

6 Graphics exchange standards and Database management systems. 1

7 Parametric representation of lines: Locating a point on a line, parallel lines 1

8 perpendicular lines, distance of a point, Intersection of lines 1

9 Parametric representation of circle, Ellipse, parabola and hyperbola 1

10 Synthetic Curves: Concept of continuity 1

11 Cubic Spline: equation, properties and blending 1

12 Bezier Curve: equations, properties; Properties and advantages of B-Splines

and NURBS. 1

13 Various types of surfaces along with their typical applications. 1

14 Geometry and Topology, Comparison of wireframe, surface and solid

models 1

15 Properties of solid model, properties of representation schemes, Concept of

Half-spaces 1

16 Boolean operations. Schemes: B-rep, CSG, Sweep representation, ASM 1

17 Primitive instancing, Cell Decomposition and Octree encoding 1

18 Homogeneous representation; Translation 1

19 Scaling, Reflection 1

20 Rotation, Shearing in 2D and 3D 1

21 Orthographic and perspective projections 1

22 Window to View-port transformation. 1

23 Review of stress-strain relation and generalized Hooke's Law 1

24 Plane stress and Plane strain conditions 1

25 Concept of Total Potential Energy 1

26 Basic procedure for solving a problem using Finite Element Analysis 1

27 1-D Analysis 1

28 Concept of Shape function and natural coordinates 1

REFERENCES

S. No. TITLE AUTHOR PUBLISHER / EDITION

1 CAD / CAM: Theory and Practice Ibrahim Zied, McGraw-Hill

2 Computer Graphics Hearn E J and Baker M

P Pearson.

3 Introduction to Finite Elements in

Engineering

Chandrupatla T A and

Belegundu A D, PHI.

4 A First Course in the Finite

Element Method

Logan D,

Cengage.

29 strain - displacement matrix 1

30 derivation of stiffness matrix for structural problems 1

31 properties of stiffness matrix 1

32 1-D structural problems with elimination and penalty approaches 1

33 1-D thermal and fluid problems 1

34 Trusses and Beams 1

35 Formulation of stiffness matrix 1

36 simple truss problems to find displacement 1

37 reaction and stresses in truss members 1

38 Structural analysis using Euler-Bernoulli beam element 1

39 Higher Order Element 1

40 CST element stiffness matrix formulation 1

41 shape functions 1

42 applications of Quad 1

43 Axisymmetric elements. 1

ASSIGNMENT TOPICS

S. No. TOPIC

1 Introduction of CAD-CAM

2 Curve and surfaces

3 Mathematical representation of solids

4 Geometrical modeling

5 Finite element analysis

ASSIGNMENT 1

Sr.

No. Name of Question Remarks

1 Explain DDA algorithm for generation of line.

2 Explain various input output devices used in CAD.

3 Write down differences between Raster Scan and Vector Scan Displays

4 Identify the pixel locations that will be chosen by the DDA algorithm while scan

converting a line from screen coordinate (10, 30) to (19, 36)

5 List and explain the important parameters to be considered while selecting CAD

systems. List the different application of CAD in mechanical engineering

6 What are the advantages of CAD in design? Explain application of Computers to the

design process

7 What are different software package used in CAD. Give specification of CAD work

station.

8 Why graphic standard plays important roles in CAD. Enlist various graphic standards

with full name.

9 Discuss Bresenham’s Circle algorithm with suitable example.

10

Write Bresenham’s algorithm for generation of line also indicate which raster

locations would be chosen by Bresenham’s algorithm when scan converting a line

from screen co-ordinate (1, 0) to (10,3).

11 Differentiate: Computer Aided Design & Computer Aided Drafting.

12 Explain Product Cycle: i) Conventional ii) With the help of CAD/CAM.

13 Explain Database Management System in CAD.

14 Explain different Co-ordinate Systems in detail.

ASSIGNMENT 2

Sr.

No

. Name of Question

Remark

s

1 Explain Geometrical Modelling. Explain wireframe modeling with its advantages and

disadvantages.

2 Explain the non-parametric representation of curves. State its limitations.

3 Explain the parametric representation of curves.

4 What do you understand by analytic curves and synthetic curves?

5 Explain the parametric equations for the following analytic curves?

6 With neat sketch, explain Hermite cubic Spline curve.Obtain the Parametric equation

for Hermite cubic spline curve.

7 With the neat sketch, explain the characteristics of Bezier curve.

8 With the neat sketch, explain the B-spline curve. State its advantages.

9 What do you understand by 2D, 2 and 1/2D and 3D wire-frame models?

10 What do you understand by parametric and non-parametric representation of

Surfaces?

11

Explain the following entities used in surface modeling:

(i) Plane surface, (ii) Ruled surface, (iii) Tabulated surface, (iv) Surface of

revolution, (iii) Tabulated surface, (iv) Surface of revolution, (vii) Coons patch,

(viii) Fillet surface, (ix) Offset surface

ASSIGNMENT 3

Sr.

No

. Name of Question

Remark

s

1 What do you understand by geometry and topology in solid modeling?

2 What are the commonly used primitives in solid modeling?

3 What do you understand by C-rep and B-rep approaches? Compare them.

4 With neat sketches, explain the various Boolean operations used in CSG solid

modeling.

5 What are the various types of sweeps used in solid modeling?

ASSIGNMENT 4

Sr.

No

. Name of Question

Remark

s

1 What is two dimensional transformations? Discuss Translation, Rotation, Scaling, Shear

and Mirror with suitable examples.

2 What is the significance of homogenous coordinates in Geometric transformations?

3 What do you understand by composite transformations? Discuss with suitable example.

4 What do you mean by Windows to Viewport coordinate transformation?

5

Explain in brief about following with respect to computer graphics.

Orthographic projections

Perspective Projections

6 Reflect the diamond shape polygon whose vertices are A(-3,0), B(0,-2), C(3,0), D(0,2)

about an arbitrary line L which is represented by equations y=0.5x+1.

7

A triangle ABC with vertices A(30,20), B(90,20) and C(30,80) is to be scaled by factor

0.5 about a point X(50,40). Determine (i) the composition matrix and (ii) the

coordinates of the vertices for a scaled triangle.

8 A triangle ABC having coordinates A(15, 15), B(25, 25) and C(15, 35) is rotated by 30o

clockwise about the vertex B. Determine the new vertex positions after rotation.

9

A rectangle ABCD having vertices A(10,15), B(25, 15), C(25, 25) and D(10, 25) is to be

reflected about a line passing through points P(25, 20) and Q(10, 30). Determine the

vertices of the reflected rectangle

10

A tetrahedron is defined by points A(10, 15, 20), B(30, 15, 20), C(10, 25, 20) and D(20,

20, 50). Calculate the new coordinates of the tetrahedron, if it is rotated about X axis by

60o in CCW direction followed by rotation about Y axis by 45o in CCW direction

11

A triangle ABC with vertices A(30,20), B(90,20) and C(30,80) is to be scaled by factor

0.5 about a point X(50,40). Determine (i) the composition matrix and (ii) the

coordinates of the vertices for a scaled triangle.

12

A rectangle ABCD has vertices A(1,1), B(2,1) ,C(2,3) and D(1,3) . It has to be rotated by

300 CCW about point P (3,2). Determine (i) the composite transformations of matrix and

(ii) the new coordinates of rectangle=

ASSIGNMENT 5

Sr.

No

. Name of Question Remarks

1 Discuss different types of analysis for FEM, also mention advantages and limitations of

FEM

2 Explain the various steps required to solve mechanical problem using finite element

analysis.

3

Explain the following methods

Rayleigh Ritz

Galerkin

4 Explain the shape function in natural co-ordinate system

5 Explain Penalty approach and Elimination approach for FEA.

6 Explain with example Plain stress and Plain strain conditions.

7 State and describe the various types of elements used in the finite element analysis.

8 Explain Constant strain energy triangular Element and its Shape function.

9

Axial load P = 300 KN is applied at 20° C to the rod as shown in fig. The temperature

is then raised to 60° C. The coefficient of thermal expansion for Aluminium is 23x10-6

per °C and Steel is 11.7x10-6

per °C. A(Al) = 900 mm2, A(Steel) = 1200 mm2, E(Al) =

70 x 109 N/m

2, E(Steel) = 200 x 10

9 N/m

2. Using FEM,

(1) Determine the nodal displacement and element stresses.

(2) The reaction forces at the supports.

10

Consider the stepped bar shown in fig. -1. A load P=200 KN is applied as shown.

Determine the nodal displacements, element stresses, and support reactions. use

elimination approach for boundary conditions. Take E= 2x105 N/mm2.

11

A two step as shown in figure is subjected to thermal loading conditions. An axial load

P = 200 x 103 N applied 20° C to the end. The temperature of the bar is raised by 50 °

C.

Calculate:

(i) Element stiffness matrix

(ii) Global stiffness matrix

Consider E1 = 70 x 103 N/mm2, E2 = 200 x 10

3 N/mm2, A1 = 700mm2, A2 =

1000mm2, α1 = 23 x 10-6

per °C and α2 = 11.7 x 10-6

per °C.

12

A truss is made up of steel material with a bar size of 2cm as shown in figure:

Calculate:

(i) Element stiffness matrix for each element

(ii) Global stiffness matrix for entire truss

13

Figure shows the compound section fixed at both ends. Estimate the reaction forces at

the supports and the stresses in each material when a force of 200 kN is applied at the

change of cross section.

Mid paper

Laxmi Institute of Technology , Sarigam

Approved by AICTE, New Delhi; Affiliated to Gujarat Technological University, Ahmedabad

Academic Year 2018-19

Centre Code: 086 Examination : Mid Sem 1 Branch: Auto / Mech Semester: 6th Sub Code: 2161903 Sub: Computer Aided Design Date:02/02/2019 Time: 9:00 am to 10:00 am Marks: 20 Q1 Draw a diagram showing product cycle with the implementation of CAD. 5 Q2 Identify the pixel locations that will be chosen by the DDA algorithm while scan converting a line

from screen coordinate (5, 7) to (12, 13).

5

OR

Q2 Explain Bresenham’s flowchart for generation of line. 5 Q3 Write Bresenham’s algorithm. Determine Intermediate pixel for line starting from (1,1) and (8,5). 5

OR Q3 Explain steps in Finite Elements analysis in detail 5 Q4 A stepped shaft as shown in figure, Determine the stress and nodal displacement for each elements.

Assume uniform material for shaft having modulus of elasticity 200 GPa and axial force of 35 KN.

5