SOAL-SOAL PSIKOLOGI INDUSTRI DAN ORGANISASI
Pertemuan 21:
Psikologi Rekayasa
1. Define ergonomics and describe its role and function in the workplace.
a. Ergonomics - the design of machines and equipment for human use, and the
determination of the appropriate human behaviors for the efficient operation of
the machines. The field is also called human factors, human engineering, and
engineering psychology.
b. Its role and function in the workplace is the design of the machinery and
equipment employees use to do their jobs and the workspaces in which those
tasks are performed.
2. When did the field of human factors begin? How did its early efforts help save the lives
of military pilots?
a. Prior to World War II the design of machinery, equipment, and industrial plants
was solely the responsibility of engineers. Engineers made machines without
considering the human factor. The worker was adapted to machines through timeand-motion studies.
b. Engineering psychology evolved in response to the complexity of weaponry in
WWII. Poor design resulted in many accidents. Engineering psychologists
developed a consistent, standard arrangement of controls and instruments in the
cockpit, so that they were similar across all aircraft. This saved pilots’ lives. To
deal with human factors in aircraft accidents, the NTSB added engineering
psychologists to its staff.
3. Give an example of how human factors research has reduced the chances of being
involved in a car crash.
a. Human factors resulted in safer automobiles.
i. Brightness of headlights
ii. Position, color, and brightness of tail lights
iii. The layout of dashboard controls and displays
iv. Effect of tinting
v. Cell phone use by drivers
4. Who was Frederick Taylor and what did he do to improve the job of shoveling?
a. F.W. Taylor (1898) was a promoter of scientific management.
b. He performed the first empirical demonstration of the relationship between work
tools and worker efficiency.
i. He introduced shovels of different sizes for handling different materials,
saving a steel company $78,000 per year.
ii. He introduced the concept of incentive pay, allowing workers to increase
their wages by up to 60 percent for higher productivity.
5. How did Frank and Lillian Gilbreth change the way jobs are performed?
a. The Gilbreths (1911) were interested in the mechanics of job performance - to
eliminate all unnecessary motions. They started with improving the efficiency of
brick laying (increasing the rate of brick laying from 120 to 350 bricks an hour,
reducing motions from 18.5 to 4.5).
b. Time and motion engineers have applied their techniques for many years.
6. How did the Gilbreths apply time-and-motion study to everyday life?
a. They organized their household and personal lives around the principles of timeand-motion economy.
b. He saved 4 seconds by buttoning his vest bottom up; saved 17 seconds by using
two brushes to shave, one for each hand.
c. They attempted to schedule the activities of their 12 children.
7. Describe several rules for increasing the ease, speed, and accuracy of manual jobs that
developed from the findings of time-and-motion studies.
a. Minimize the reaching distance from the worker.
b. Symmetrical movements of both hands.
c. Hands should never be idle.
d. Hands never do tasks that can be performed by other parts of the body
e. Work materials should be held by a vice.
f. Workbench adjusted to prevent fatigue.
8. What is the relationship of displays, controls, and the human operator in a personmachine system? Give an example of a person-machine system.
a. Person-machine system - a system in which human and mechanical components
operate together to accomplish a task.
i. The operator receives input on the status of the machine from displays.
ii. The operator then regulates the equipment by using the controls to initiate
some action.
iii. Cycle: displays - sensing - human information processing - controlling controls - machine information processing - displays.
b. Example - You are driving - you receive information from the speedometer - you
perceive you’re driving too fast and ease up on the accelerator, thereby reducing
the flow of fuel to the engine, which slows the speed of the car, which affects the
displays.
9. What advantages do humans have over machines? In what ways are machines superior to
humans?
a. Humans are more flexible, can learn from errors, and can improvise.
b. Machines don’t get bored; detect stimuli beyond human capabilities; monitor
reliably for extended periods; make large numbers of rapid, accurate calculations;
apply continuous and rapid physical force; and engage in repetitive activities.
10. How would you design a workspace for a person who is assembling and testing cell
phones, so that the job can be performed rapidly and safely?
a. Place all materials in order in which they’ll be used. Preposition tools for use. All
parts and tools should be within 28”. Heights of all working surfaces should be
adjustable. Hand tools should be designed for use without bending wrists.
11. What is human anthropometry? How is it applied to workspace design? How is it used in
the field of transportation, such as subway cars?
a. Human anthropometry - a branch of engineering psychology concerned with the
measurement of the physical structure of the body.
b. It is applied to workspace design to determine normal and maximum reaching
distances, tool and desk height and arrangement, size and shape of seats, and
viewing angles for video display terminals.
c. The seats in subways have become roomier. This also results in a reduction in the
number of seats available.
12. Under what conditions is the visual presentation of information superior to the auditory
presentation of information? Give an example that involves your automobile.
a. Visual presentation is appropriate when the message is long or complex; the
environment is noisy, the auditory channels are overloaded; and there are multiple
kinds of information to be displayed simultaneously.
b. Example: Speedometer; temperature; RPM; error messages and warnings
triggered by computer.
13. Describe three types of visual displays and note what kind of information is best
displayed on each.
a. Quantitative displays - displays that present a precise numerical value, such as
speed, altitude, or temperature.
b. Qualitative displays - displays that present a range rather than a precise numerical
value. They are frequently used to show whether components, such as engine
temperature, are operating in the safe or unsafe range.
c. Check reading displays - displays that tell the operator whether the system is on or
off, safe or unsafe, or operating normally or abnormally. (Example: add oil
warning light).
14. What are some problems with auditory alarm systems? How would you correct these
problems?
a. Almost half of auditory alarms are ignored.
b. “Nuisance alarms” serve only to add clutter or confusion to a critical and
demanding job. They do not provide useful or meaningful information for the
human operator.
15. What is the field of telematics? Why is it important in engineering psychology?
a. Telematics - refers to the wireless information technology you may have in your
car, such as GPS navigation systems, satellite radio, or built in wireless phone.
b. Engineering psychologists are involved in determining the nature and extent of
distractions associated with this wireless technology and how best to equip the
human operator to deal with them.
16. What has human factors research learned about (a) the use of cell phones while driving,
(b) leather versus fabric seating, (c) furniture for the classroom?
a. Data are incomplete, but the use of cell phones is thought to be a major
contributor to accidents. The chance of an accident is 4.3 times greater when the
driver is using a cell phone.
b. Fabric seats are more comfortable; leather seats cause us to perspire.
c. Furniture for the classroom is found often to be poorly designed for the use and
comfort of children. Chairs are often too high, the seats too deep, and desks too
deep.
17. How would you design a study to determine the most efficient ice cream scoop to
minimize muscle strain?
a. Measure the physical difficulty of scooping the ice cream. Compare the results.
b. Measure at varying temperatures for the ice cream. Compare the results.
c. Do the same for different models. Measure the results.
18. What factors should be considered in designing a computer work station?
a. Research findings indicate the computer keyboard should be downward sloping
15 degrees to reduce discomfort in the neck and back. An angle of 17 degrees for
the computer monitor permits the best posture arrangement for viewing angle.
The viewing distance should be 15-30 inches. Table and chair height should be
adjustable (15-20” for the chair pan; 26-32” for the table). Screen height on the
table should be 26-32”. A virtual mouse like a joystick eases tension.
19. What are the most frequent complaints from computer users?
a. Blurred vision, eyestrain, fatigue, and pain in the wrists, hands, shoulders, neck,
and back.
20. Would you rather read a magazine article on your computer screen or printed on paper?
Which format provides for faster reading and better understanding?
a. Paper format provides faster reading and higher comprehension.