JNTUH CAD/CAM (UNIT NO-I PPT)

1. 1
Introduction to CAD/CAM

2. Computer-Aided Design (CAD)
 Use of computer systems to assist in
the creation, modification, analysis,
and optimization of a design
 Typical tools:
 Tolerance analysis
 Mass property calculations
 Finite-element modeling and
visualization
 Defines the geometry of the design

3. Computer-Aided Manufacturing (CAM)
 Use of computer systems to
plan, manage, and control
manufacturing operations
 Direct or indirect computer
interface with the plant’s
production resources
 Numerical control of machine
tools
 Programming of robots

4. Computer-Aided Engineering (CAE)
 Use of computer systems to
analyze CAD geometry
 Allows designer to simulate
and study how the product
will behave, allowing for
optimization
 Finite-element method
(FEM)
 Divides model into
interconnected elements
 Solves continuous field
problems

5. Computer-Aided Design Process
 Two types of activities: synthesis and analysis
 Synthesis is largely qualitative and hard to capture
on computer
 Analysis can be greatly enhanced with computers
 Once analysis is complete, design evaluation- rapid
prototyping
 Software packages for design optimization

6. Components of CAD/CAM/CAE Systems
 Major component is hardware
and software allowing shape
manipulation
 Hardware includes graphic
devices and their peripherals
for input and output
operations
 Software includes packages
that manipulate or analyze
shapes according to user
interaction

7. Components of CAD/CAM/CAE Systems

8. Hardware Components
 Graphic device is composed of a display
processing unit, a display device, and one or
more input devices
 Input devices:
 Mouse
 Space ball
 Data tablet with a puck or stylus
 Keyboard
 Output Devices:
 Plotters
 Color laser printers

9. Software Components
 CAD software allows the designer to create and
manipulate a shape interactively and store it
 CAM software plans, manages and controls the
operations of a manufacturing site
 CAE software analyzes design geometry, allowing
designer to study product behavior

10. Windows-Based CAD Systems
 User interface is similar to Windows
 Employs component technology, in which best key
software elements are selected from among available
software
 Use object-oriented technology, which modularizes
the program
 Capable of either parametric or variational modeling
 Internet support

11. CAD/CAM
11
• CAD/CAM = Computer Aided Design and
Computer Aided Manufacturing. It is the
technology concerned with the use of computers
to perform design and manufacturing functions.

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• CAD can be defined as the use of computer
systems to perform certain functions in the
design process.
• CAM is the use of computer systems to plan,
manage and control the operations of
manufacturing plant through either direct or
indirect computer interface with the plant’s
production resources.

13. Rapid Prototyping
 Layer by layer fabrication of
three-dimensional physical
models from CAD
 Fast and inexpensive
alternative for producing
prototypes and functional
models
 Build parts in thin layers
 Minimum operation time;
typically runs unattended
Rapid Prototyping
has surgical
applications

14. Medical Modeling - Zcorp

15. Rapid Prototyping Cycle

16. Rapid Prototyping Cycle
 .STL is standard file format
for all U.S. rapid
prototyping systems
 Preprocessing prepares
.STL file for various rapid
prototyping systems
 Build process can last from
a few hours to several days
 Post processing: removal of
part from machine, support
removal, sanding

17. Rapid Prototyping Process (Damvig)
“A computer-controlled laser beam is scanned across the surface
of a vat of liquid photopolymer, instantly solidifying the liquid at
each point of contact. Using data generated from a CAD file,
individual cross-sections of the three-dimensional geometry are
solidified in turn to build up a solid part layer by layer. In this
way even highly complex geometries can be built in a few hours
without requiring any tools. “

18. 18
From CAM definition, the application of CAM
falls into two broad categories:
1. Computer monitoring and control .
Computer Process
Process
data

19. 19
2. Manufacturing support application .
Control signals
Computer Mfg
operation
s
Process data

20. The Product Cycle and CAD/CAM
20
In order to establish the scope and definition of
CAD/CAM in an engineering environment and
identify existing and future related tools, a study
of a typical product cycle is necessary. The
following Figure shows a flowchart of such a cycle.

21. 21
The Manufacturing Process
The Design Process
Synthesis
Analysis The CAD Process
The CAM Process
Design
needs
Design
definitions,
specifications,
and requirements
Collecting
relevant design
information and
feasibility study
Design
conceptualization
Design
modeling and
simulation
Design
analysis
Design
optimization
Design
evaluation
Design
documentation and
communication
Process
planning
Order
materials
Design and
procurement of
new tools
Production
planning
NC, CNC, DNC
programming
Production
Quality
control
Packaging
Marketing
Shipping
Typical Product Life Cycle

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 The product begins with a need which is
identified based on customers' and markets'
demands.
 The product goes through two main processes
from the idea conceptualization to the finished
product:
1. The design process.
2. The manufacturing process.
The main sub-processes that constitute the design
process are:
1. Synthesis.
2. Analysis.

23. Implementation of a Typical CAD Process on a
CAD/CAM system
23
Delineation of
geometric
model
Definition
translator
Geometric
model
Design and
Analysis algorithms
Drafting and
detailing
Documentation
To CAM Process
Interface
algorithms
Design changes

24. CAD Tools Required to Support the Design Process
24Design phase Required CAD tools
Design conceptualization Geometric modeling techniques;
Graphics aids; manipulations; and
visualization
Design modeling and simulation Same as above; animation; assemblies;
special modeling packages.
Design analysis Analysis packages; customized
programs and packages.
Design optimization Customized applications; structural
optimization.
Design evaluation Dimensioning; tolerances; BOM; NC.
Design communication and
documentation
Drafting and detailing…

25. Implementation of a Typical CAM Process on a
CAD/CAM system
25
Geometric
model
Interface
algorithms
Process
planning
Inspection
Assembly
Packaging
To shipping and marketing
NC programs

26. 26
Manufacturing phase Required CAM tools
Process planning CAPP techniques; cost
analysis; material and
tooling specification.
Part programming NC programming
Inspection CAQ; and Inspection
software
Assembly Robotics simulation and
programming
CAM Tools Required to Support the Design Proces

27. Automation and CAD/CAM
27
Automation can be defined as the technology
concerned with the application of complex
mechanical, electronic, and computer-based
systems in the operation and control of
manufacturing systems.

28. 28
TTypes of Manufacturing Systems
1. Continuous-flow processes. Continuous dedicated production of
large amount of bulk product. Continuous manufacturing is
represented by chemicals, plastics, petroleum, and food industries.
2. Mass production of discrete products. Dedicated production of
large quantities of one product (with perhaps limited model
variations). Examples include automobiles, appliances and engine
blocks.
3. Batch production. Production of medium lot sizes of the same
product. The lot may be produced once or repeated periodically.
Examples: books, clothing and certain industrial machinery.
4. Job-shop production. Production of low quantities, often one of a
kind, of specialized products. The products are often customized
and technologically complex. Examples: prototypes, aircraft,
machine tools and other equipment.

29. 29
Production
quantity
Continuous-
flow
production Mass
production
Batch
production
Job shop
production
Product variety

30. 30
Category Automation achievements
Continuous-flow process •Flow process from beginning to end
•Sensors technology available to measure
important process variables
•Use of sophisticated control and optimization
strategies
•Fully computer automated lines
Mass production of discrete products •Automated transfer machines
•Dial indexing machines
•Partially and fully automated assembly lines
•Industrial robots for spot welding, part handling,
machine loading, spray painting, etc.
•Automated material handling systems
•Computer production monitoring
Batch production •Numerical control (NC), direct numerical
control (DNC), computer numerical control
(CNC).
•Adaptive control machining
•Robots for arc welding, parts handling, etc.
•CIM systems.
Job shop production •Numerical control, computer numerical control

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Most of the automated production systems implemented today
make use of computers. CAD/CAM in addition to its particular
emphasis on the use of computer technology, is also
distinguished by the fact that it includes not only the
manufacturing operations but also the design and planning
functions that precede manufacturing.
To emphasize the differences in scope between automation and
CAD/CAM, consider the following mathematical model:
Computer Technology in
Automation

32. Advantages of CAD/CAM systems
32
• Greater flexibility.
• Reduced lead times.
• Reduced inventories.
• Increased Productivity.
• Improved customer
service.
• Improved quality.
• Improved
communications with
suppliers.
• Better product design.
• Greater manufacturing
control.
• Supported integration.
• Reduced costs.
• Increased utilization.
• Reduction of machine
tools.
• Less floor space.

33. CAD/CAM
33
 CAD/CAM is a term which means computer-aided design
and computer- aided manufacturing. It is the technology
concerned with the use of digital computers to perform
certain functions in design and production. This technology
is moving in the direction of greater integration of design
and manufacturing, two activities which have traditionally
been treated as distinct and separate functions in a
production firm. Ultimately, CAD/CAM will provide the
technology base for the computer-integrated factory of the
future.

34. 34

35. Main Applications of Computer Aided Design (CAD)
35
 Plotter/cutters Using 2D CAD: graphics software these
machines can draw or cut 2D shapes on paper, card or
self-adhesive vinyl sheets.
 Laser cutting Using 2D CAD: Graphics software these
machines can cut or engrave a wide variety of materials
such as card, plywood, acrylic sheet, textiles, glass.
 Milling Typically 2.5D machining: if the uses 2D CAD
files as the source and cuts in x and y directions (parallel
to the machine bed) while lowering the tool progressively
through several steps to cut out an object using a rotating
tool.
 Turning
 Milling
 printing

36. The key benefits of CAD/CAM
36
 Increased range of design ideas
 Improved accuracy
 Easy of modification
 Repeatability of output
 Quality of output
 Reduction of wastage
 Less time taken
 Improved engineering productivity
 Shorter lead times
 Reduced engineering personnel requirements
 Customer modifications are easier to make
 Faster response to requests for quotations
 Avoidance of subcontracting to meet
schedules
 Minimized transcription errors
 Improved accuracy of design
 In analysis, easier recognition of component
interactions
 Provides better functional analysis to reduce
prototype testing
 Assistance in preparation of documentation
 Designs have more standardization
 Better designs provided
 Improved productivity in tool design
 Better knowledge of costs provided
 Reduced training time for routine drafting
tasks and NC part programming
 Fewer errors in NC part programming
 Provides the potential for using more existing
parts and tooling
 Helps ensure designs are appropriate to
existing manufacturing techniques
 Saves materials and machining time by
optimization algorithms

37. Basic Computer Configuration of CAD
37
 Computer Operations •
 The computer is an electronic machine that performs
the following five basic operations:
 Input
 Process
 Output
 Store
 Control

38. Input
38
 • It is the process of capturing or acquiring the
information, or it is the process of accepting data or
information, by using input the computer can do any
process.
 Information or data that is entered into a computer
or computer device using an input device.
 Input
 Data is gathered
 Manually
 Automatically
 Both

39. •
Types of Computer Input
39
 Data : the raw facts given to the computer.
 • Programs : the sets of instructions that direct the
computer.
 • Commands :special codes or key words that the
user inputs to perform a task.
 • User response : the user's answer to the computer's
question.

40. Processing
40
 Arithmetic / Logic Unit (ALU) • The part of a computer that performs all
arithmetic computations, such as addition and multiplication, and all
comparison operations.
 Control Unit :The control unit is the circuitry that controls the flow of data
through the processor, and coordinates the activities of the other units
within it.
 Input / Output Unit (I/O Unit) : The computer components that control
input and output devices.
 Computer Output : It is the result, which comes from the transformation
process or it is the outcome of the process.
 Anything that comes out of a computer.
 Example: –
 Report
 Music
 Graphic
 Video clip.

41. Basic Computer Components
41
 Motherboard Components directly attached to the motherboard include:
 CPU Chipset
 Random-Access Memory (RAM)
 Read-Only Memory (ROM)
 BIOS (Basic Input Output System)
 Buses
 Ports.
 Hard disk :It used to store computer data and program. It can hold more
data and are faster than floppy disks.
 Input Devices:
 Keyboard, mouse
 Output Devices
 Printer, speakers
 Operating System
 Windows

42. Types of database models
42
 Hierarchical database model.
 Relational model.
 Network model.
 Object-oriented database model.
 Entity-relationship model.
 Document model.
 Entity-attribute-value model.
 Star schema.

43. 3-D WIRE FRAME MODELLING
43

44. 44

45. 3D MODELLING FIG
45

46. 46

47. Curve fitting Techniques
47

48. Parametric and non Parametric Statistics
48

49. B-Spline
49

50. Bezier and cubic B-Spline
50

51. AUTOMATION AND CAD/CAM
51
 Automation is defined as the technology concerned with the application
of complex mechanical, electronic, and computer-based systems in the
operation and control of production. It is the purpose of this section to
establish the relationship between CAD/CAM and automation.
 Continuous-flow processes
 Mass production of discrete products
 Batch production
 Job shop production

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 1. Continuous-flow processes :Continuous dedicated
production of large amounts of bulk product. Examples
include continuous chemical plants and oil refineries
 2.Mass products :Production of discrete Dedicated production
of large quantities of one product (with perhaps limited model
variations). Examples include automobiles, appliances, and
engine blocks.
 3. Batch production :Production of medium lot sizes of the
same product or component. The lots may be produced once
or repeated periodically. Examples include books, clothing,
and certain industrial machinery.
 4. Job shop production :Production of low quantities, often
one of a kind, of specialized products. The products are often
customized and technologically complex. Examples include
prototypes, aircraft, machine tools, and other equipment.

53. THE APPLICATION OF COMPUTERS FOR DESIGN
53
 The various design-related tasks which are
performed by a modem computer-aided design-
system can be grouped into four functional areas:
 Geometric modeling
 Engineering analysis
 Design review and evaluation
 Automated drafting

54. Benefits in manufacturing
54
 The benefits of computer-
aided design carry over into
manufacturing. As
indicated previously, the
same CAD/CAM data base
is used for manufacturing
planning and control, as
well as for design. These
manufacturing benefits are
found in the following
areas
 Tool and fixture design for
manufacturing Numerical
control part programming
Computer-aided process
planning
 Assembly lists (generated
by CAD) for production
Computer-aided inspection
 Robotics planning Group
technology
 Shorter manufacturing lead
times through better
scheduling

55. THANK YOU
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