Engineering Fundamentals: An Introduction to Engineering, 4th ed.c

6.7 Engineering Components and Systems 147

collar, pockets, the chest section, and the back section (see Figure 6.5). Each component serves

a purpose: The pockets were designed to hold things, the sleeves cover our arms, and so on. The

main function of the zipper is to allow us to open and close the front of the jacket freely. It too

consists of smaller components. Think once more about the overall purpose of the coat and the

function of each component. A well-designed coat not only looks appealing to the eyes but

also has functional pockets and keeps us warm during the winter.

Engineering systems are similar to a winter coat. Any given engineered product or engi-

neering system can be divided into smaller, manageable subsystems, and each subsystem can be

further divided into smaller and smaller components. The components of a well-designed engi-

neering system should function and fit well together so that the primary purpose of the prod-

uct is attained. Let us consider another common example. The primary function of a car is to

move us from one place to another in a reasonable amount of time. The car must provide a com-

fortable area for us to sit within. Furthermore, it must shelter us and provide some protection

from the outside elements, such as harsh weather and harmful objects outside. The automobile

consists of thousands of parts. When viewed in its entirety, it is a complicated system. Thou-

sands of engineers have contributed to the design, development, testing, and supervision of the

manufacture of an automobile. These include electrical engineers, electronic engineers, com-

bustion engineers, materials engineers, aerodynamics experts, vibration and control experts, air-

conditioning specialists, manufacturing engineers, and industrial engineers.

When viewed as a system, the car may be divided into major subsystems or units, such as

electrical, body, chassis, power train, and air conditioning (see Figure 6.6). Each major com-

ponent can be further subdivided into smaller subsystems and their components. For example,

the main body of the car consists of doors, hinges, locks, windows, and so on. The windows are

controlled by mechanisms that are activated by hand or motors. And the electrical system of a

car consists of a battery, a starter, an alternator, wiring, lights, switches, radio, microprocessors,

and so on. The car’s air-conditioning system consists of components such as a fan, ducts, dif-

fusers, compressor, evaporator, and condenser. Again, each of these components can be further

divided into yet smaller components. For example, the fan consists of an impeller, a motor,

Sleeve

Pocket

Zipper

Insulation

material

Collar

■Figure 6.5

A simple system and its

components.

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