The document discusses the conventional design process and CAD design process. The conventional design process consists of 6 steps: recognition of need, problem definition, synthesis, analysis and optimization, evaluation, and presentation. The CAD design process consists of 4 steps: geometric modeling, engineering analysis, design review and evaluation, and automated drafting. The CAD design process improves engineering productivity, shortens lead times, provides better designs, and makes modifications and requests for quotations easier compared to the conventional design process.

1. CAD/CAM
TOPIC: CONVENTIONAL AND CAD DESIGN PROCESS
By
J KUMAR CHANDRA,
ASST. PROF.,
DEPARTMENT OF ME,
NNRG-HYDERABAD

2. DESIGN PROCESS(CONVENTIONAL)
• Before examining the several facets of computer-aided
design, let us first consider the general design process.
which consists of six identifiable steps or phases:-
• 1. Recognition of need
• 2. Definition of problem
• 3. Synthesis
• 4. Analysis and optimization
• 5. Evaluation
• 6. Presentation

3. DESIGN PROCESS(CONVENTIONAL)
1. Recognition of need
Someone recognizes the need that can
be satisfied by a new design
2. Problem definition
Specification of the item
3. Synthesis
creation and conceptualization

4. DESIGN PROCESS(CONVENTIONAL)
4. Analysis and optimization
the concept is analyzed and redesigned
5. Evaluation
compare design against original specification or
checking errors.
6. Presentation
documenting the design (e.g. drawing)

5. FLOW CHART OF DESIGN PROCESS

6. DESIGN PROCESS(NON-CONVENTIONAL)
• in CAD design process, the process can be completed
with in only 4 steps
• 1. Geometric modeling
• 2. Engineering analysis
• 3. Design review and evaluation
• 4. Automated drafting

7. Geometric modeling
• In computer-aided design, geometric modeling is concerned with the
computer-compatible mathematical description of the geometry of an
object. The mathematical description allows the image of the object to be
displayed and manipulated on a graphics terminal through signals from
the CPU of the CAD system

8. Engineering analysis
• In the formulation of nearly any engineering design project, some type of
analysis is required. The analysis may involve stress-strain calculations,
heat-transfer computations, or the use of differential equations to
describe the dynamic behavior of the system being designed.
• Provides properties of a solid object being analyzed, such as the
surface area, weight, volume

9. Design review and evaluation
• Checking the accuracy of the design can be accomplished conveniently on
the graphics terminal. Semiautomatic dimensioning and tolerance
routines which assign size specifications to surfaces indicated by the user
help to reduce the possibility of dimensioning errors

10. Automated drafting
• Automated drafting involves the creation of hard-
copy engineering drawings directly from the CAD
data base

11. CONVENTIONAL DESIGN PROCESS Vs CAD DESIGN PROCESS

12. BENEFITS OF CAD DESIGN PROCESS OVER
CONVENTIONAL DESIGN PROCESS
• 1. Improved engineering productivity
• 2. Shorter lead times
• 3. Better designs provided
• 4. Customer modifications are easier to make
• 5. Faster response to requests for quotations
• 6. Avoidance of subcontracting to meet schedules
• 7. Minimized transcription errors
• 8. Improved accuracy of design
• 9. In analysis, easier recognition of component interactions
• 10. Provides better functional analysis to reduce prototype
testing
• 11. Assistance in preparation of documentation