44 Chapter 3 Introduction to Engineering Design
the product is going to be fabricated. You will consult pertinent codes and standards and make
sure that your design will be in compliance with these codes and standards. We will discuss engi-
neering codes and standards in Section 3.11.Step 6: Evaluation
Analyze the problem in more detail. You may have to identify critical design parameters and con-
sider their influence in your final design. At this stage, you need to make sure that all calcula-
tions are performed correctly. If there are some uncertainties in your analysis, you must perform
experimental investigation. When possible, working models must be created and tested. At this
stage of the design procedure, the best solution must be identified from alternatives. Details of
how the product is to be fabricated must be worked out fully.Step 7: Optimization
Optimization means minimization or maximization. There are two broad types of design: a
functional design and an optimized design. A functional design is one that meets all of the
preestablished design requirements but allows for improvement to be made in certain areas.
To better understand the concept of a functional design, we will consider an example. Let us
assume that we are to design a 3-meter-tall (10 ft) ladder to support a person who weighs
1335 newtons (300 pounds) with a certain factor of safety. We will come up with a design that
consists of a steel ladder that is 3 meter tall (10 ft) and can safely support the load of 1335 N
(300 lb) at each step. The ladder would cost a certain amount of money. This design would
satisfy all of the requirements, including those of strength and size, and thus constitutes aTwo engineers considering
details during the design
process.
Source:Courtesy of
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