2. 2
Course Objectives
• To study how Computer Aided
Engineering is used as a tool for
engineering design and analysis.
• To study the business and social/ethics
context for developing products
4. 4
Apply your Final Year project in this course
Consider Manufacturability and Value
Engineering early in the design phase.
The Project is assessed for economy of
costs, simplicity of manufacture and
reliability.
Project
6. 6
The Design Process
Problem Definition
“If we know the problem, we
can (may) find a solution”
Clarification of the task, which
involves collecting information
about the design requirements
and the constraints on the design,
and describing these in a
specification or criteria
7. 7
Gathering Customer Needs
• Interview
• Focus groups
• Surveys
• Observation
• Library/Online
• Existing Products
• Experts
• Prior Experience
From the
Custome
r
Through
Research
From the
Design Team
The Design Process
Recognition of a need
Definition of the problem
Gathering Information
8. 8
Conceptualization
- Creativity
-Intuition
-Brainstorm
-Lateral thinking
using ingenuity, experience,
and knowledge to work out a
preliminary concept of what the
design should look like, which
involves establishment of the
functions to be included in the
design, and identification and
development of suitable
solutions.
The Design Process
9. 9
Feasibility Assessment
To ensure that the project proceeds
into the design phase on a basis of
a concept that is achievable, both
technically and within cost
constrains, and that new technology
is required only in those areas that
have been thoroughly examined and
agreed to.
Feasibility assessment period is the
time for defining the concept enough
that design can proceed with
confidence that the end product will
accomplish the intended purpose
with available resources.
The Design Process
10. 10
Establishing the PDS
This is the most important elements
in the design process because it will
set up the Principle Guidelines for
the overall design, including:
-parameters to define product
functionality and performance
- product reliability
- manufacturability
- maintainability
- availability
- testability
- etc
“If we know the problem, if we
can define the problem, we can
(may) find a solution”
The Design Process
11. 11
Establishing the PDS
The design requirements need to be specific. Although
requirements are established to be permanent and inviolate, they
should nevertheless be continuously reviewed and revalidated
during the design process, at least until the design is frozen, to
ensure that they continue to reflect the goals and objects of the
project.
Sample of PDS:
Geometry: size, dimension, tolerance for system and each parts
Function: material, structural stiffness, strength, and deformation
Manufacturing: process, quality, metrology
Cost: manufacturing, assembly, total product development, etc.
The Design Process
12. 12
- Preliminary design
Overall system configuration is
defined, a schematic, diagram,
layout, definition drawing, or
other engineering documentation
will be developed to provide
early project configuration
control and to assist in ensuring
interdisciplinary and intra-
disciplinary integration and
coordination during the detail
design phase.
The Design Process
13. 13
Detailed design
Development of a system and
specifications that completely
describes a proven and tested
design so that it can be
manufactured. It is during the
detailed design phase that the
project gets fully underway
The Design Process
14. 14
Synthesis
- a search for solutions. At this
stage, the information required
for the proposed
conceptualization is organized
and plan is devised for achieving
that particular design. To
achieve a profitable synthesis
decision, all the elements
affecting the design, including
product design, cost, and labor,
must be considered.
The Design Process
15. 15
-Analysis/optimization
- mathematical and experimental
testing of the design to make sure it
meets the criteria set forth in the
problem definition. The design
problem is broken into categories,
such as stress analysis, vibration,
fluid mechanics, and mechanism
.In each category, the design as a
whole or parts are tested for the
ability to serve their particular
function.
The Design Process
16. 16
Questions in Synthesis and
Analysis
How do you make the design
decision
-Is this a good design?
-Why this design is better
than others?
-Is my decision rational?
-Can it be made?
-How many design
parameters do I need to satisfy
the function requirements?
The Design Process
17. 17
Manufacturing
- detail design are defined
in which the dimensions,
tolerances, materials and
form of individual
components of the design
are specified in detail and
pass to manufacture
department to make the
product.
The Design Process
18. The Mechanical Design Process; D.G. Ullman
Factors influencing Success or Failure
of a Product
Product
Function
Sales
Related
Production
& Product
cost
Product Design
Business
Production
19. The Mechanical Design Process; D.G. Ullman
Factors influencing Success or Failure
of a Product
Product
Function
Sales
Related
Production
& Product
cost
Product
Design
Business
Production
Materials
Manufacturing
Process
Facilities
Product
form
Target
market
Product
promotion
Price
Cost/Risk
Planning/
Scheduling
Distribution
Coverage
20. PROCESS BY WHICH DESIGN IS
ACCOMPLISHED
1. ESTABLISH ALL CONSTRAINTS.
– Safety
– Quality
– Environmental
– Economic
– Market Requirements
– Etc.
2. ESTABLISH A SET OF SPECIFICATIONS.
3. DEVELOP A DESIGN CONCEPT.
4. USE MATHEMATICAL AND PHYSICAL MODELS TO
TEST THE DESIGN CONCEPT.
21. 5. PHYSICAL MODELS DESIGNED AND EVALUATED.
6. COMPARISONS ARE MADE TO DETERMINE THE
"DEGREE OF ACCEPTABILITY" OF EACH
DESIGN.
7. PRODUCT OPTIMIZED.
8. DRAW CONCLUSIONS AS TO THE DEGREE TO
WHICH THE DESIGN SATISFIES THE
SPECIFICATIONS.
PROCESS BY WHICH DESIGN IS
ACCOMPLISHED
