Chapter 3
Introduction to Engineering Design
Dr. Bahaa Al-Sheikh & Eng. Mohammed Al-Sumady
Intoduction to Engineering
1

Engineers, regardless of their backgrounds,
follow
certain steps when designing the
products and services we use in our every day
lives.
2
In this chapter we will
•
•
•
Introduce you
design process
to
the
engineering
Discuss the basic steps that most
engineers follow when designing a
product
Discuss the importance of considering
sustainability in design
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•
•
Introduce important design factors such as
 Teamwork
 Project scheduling
 Material selection
 Economic consideration
 Engineering standards and codes
Present cases studies in civil, mechanical/
electrical engineering
4
The main objective of this
chapter is:
To
introduce
the
steps
engineers
follow
to
successfully design products
or provide services that we
use in our everyday lives
5
Design Process – Basic Steps:
1.
Recognizing the need for a product or a service
2.
Problem definition and understanding
3.
Research and preparation
4.
Conceptualization
5.
Synthesis
6.
Evaluation
7.
Optimization
8.
Presentation
6

Step 1: Recognizing the need for a product or a
service
7
Step 2: Problem definition and understanding
•
•
•
This is the most important step in any
design process
Before you move on to the next step
 Make sure you understand the problem
 Make
sure that the problem is well
defined
Good problem solvers are those who first
fully understand what the problem is.
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Step 3:
Panning)
•
Research and preparation (Project
Collect useful information
 Search
to determine if a product
already exists
 Perhaps you could adopt or modify
existing components
 Review and organize the information
collected in a suitable manner
9
Step
4:
Brainstorming)
Conceptualization
(
Generate ideas or concepts that
could offer reasonable solutions to
your problem
10
Step 5: Synthesis
•
•
•
At this point you begin to consider details
Perform calculations, run computer models,
narrow down the type of materials to be used,
size the components of the system, and answer
questions about how the product is going to be
fabricated.
Consult pertinent codes and standards and
make sure that your design will be in
compliance with these codes and standards.
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Step 6: Evaluation
•
Analyze the problem in more detail
•
Identify critical design parameters and consider their
influence in your final design
•
Make sure that all calculations are performed correctly
•
Experimental Investigations.
•
When possible, working models must be created and
tested.
•
Best solution must be identified from alternatives
•
Details of design must be worked out fully
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13
Step 7: Optimization
maximization
•
•
–
minimization
or
Optimization is based on some particular
criterion such as cost, strength, size, weight,
reliability, noise, or performance.
Optimizing individual components of an
engineering system does not necessarily
lead to an optimized system
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



Step 7: Optimization – minimization or
maximization
Example : Designing a ladder with specific
height and safety support weight.
Consider the weight of the ladder as an
optimization criterion.
Then the problem becomes one of
minimizing the weight of the ladder without
jeopardizing its strength.
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An optimization procedure
16

Step 8: Presentation
17
Step 8: Presentation
•
•
You need to communicate your solution to
the client, who may be your boss, another
group within your company, or an outside
customer
Engineers are required to give oral and
written progress reports on a regular basis
to
various
groups;
consequently,
presentation could well be an integral part of
many other design steps
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
The marketing department at Johnson
outdoors recognized the growing interest in
environmentally friendly power sources for
their boating industry.
19


To
better
serve
the
consumer
and
environment.
Increasingly, more states were enacting
regulations banning the use of gasoline boat
motors in public water ways including lakes
and rivers.
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

Details of the project were defined.
Design specifications:
◦ The motor had to move 17 feet long Pontoon at
speed of 5 mph minimum.
◦ The motor has to run at least 2 hours on full battery
charge.
◦ The boat operator has the ability to trim and tilt
(raise the motor out the water) from a remote
console.
◦ The motor has to be compatible with industry
standard steering wheel mechanics.
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

Check if the motor already exists and meet
some or all requirements.
Look at state regulations concerning the use
of gasoline vs. Electric boat motors.
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



Engineers meet weekly to brain storm and
bounce ideas.
Review information gathered in step three.
Idea: the use of electric linear actuator in
place of hydraulic actuator.
This idea was perused further because the
potential leaks associated with hydraulic
actuators.
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



Considering details.
Make sure that their design is in compliance with
codes and standards.
Most of design work was done in ProE
Prototypes were build in machine laboratories.
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




Numerical experiments were conducted using
ProMechanica.
Finite element techniques used to study
stresses in critical components.
Numerical experiments were performed to
study the hydrodynamics.
The speed of the motor was measured over
several hours.
Acceleration and position time function were
determined and compared with competitors'’
motors.
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26




Based on results in step 6 modifications on
the
design
were
made
to
improve
performance.
Better withstand loading conditions.
More testing
Actual field testing in water and simulated life
resting in labs.
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





The
product
development
process
took
approximately 2 years.
During this period the design engineers gave
weekly progress reports.
Quarterly status oral and written reports
Final presentation was given to the Board
directors.
Presentation covers main issues regarding:
development cost, unit cost, market outlook,
performance characteristics, test results and
environmental impact.
Range from 15 min to entire afternoon.
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