ERGONOMICS Flashcards
MODULE 1: INTRODUCTION TO ERGONOMICS
Study of people at work
Ergonomics
The Greek word for work
Ergos
Meaning natural laws
Nomos
Paul Fitts described human performance as a function of five factors (labeled by the acronym, LIMET), which were:
Learning
Individual differences
Motivation
Environment
Task
Led a movement he called Scientific Management.
*A man who attracted others with his ideas and insight.
*These ideas and others generated by his contemporaries of that day started what is now known as industrial engineering.
- This group of pioneers placed little stress on product design; their primary interests were methods design, time study, and process design.
Frederick Taylor
Design Process (AAC)
Analysis of Similar System
Activity analysis
Critical Incident Study
MODULE 2: Ergonomic Criteria
Human – Centered Design Principles
Select people to fit their machines and jobs.
Principle 1-1
Take advantage of human attributes by expanding requirements for human abilities so that people can better perform their roles.
Principle 1-2
Overcome human limitations so that those limitations do not become system limitations.
Principle 1-3
Consider increasing the level and number of activities for which personnel are responsible so that they will be willing to change the functions of concern.
Principle 1-9
Be sure that the level and number of activities (tasks) allocated to each person or team forms a coherent set of activities and responsibilities, with an overall level that is consistent with the abilities and inclinations of the personnel.
Principle 1-10
Avoid changing activities when the anticipated level of performance is likely to result in regular intervention on the part of the personnel involved.
Principle 1 -11
Assure that all personnel involved are aware of the goals of the design and what roles after the changed.
Principle 1 -12
Provide training that assists personnel in gaining any newly required abilities to exercise skills, judgement, and creativity and helps them to internalize the personal value of these abilitie
Principle 1 – 13
Involve personnel in planning and implementing the changes from both a system-wide and individual perspective, with particular emphasis on making the implementation process minimally disruptive.
Principle 1-14
Assure that personnel understand both the abilities and limitation of the new technology and how to monitor and intervene appropriately, and retain clear feelings of responsibility for system operation.
Principle 1 -15
Used to judge problem solutions and alternative designs. A variety of criteria are typically used in ergonomic design. Some relate to the job and others to human performance,
Ergonomic Criteria
- It is important to measurement of productivity, and it is almost everything in the design of sports products.
- For this reason, industrial operations are frequently time studied over several cycles of production,
Speed
- When errors occur, (____) declines. Just as speed and time are complementary, so are accuracy and error
- · Speed and (____) are often inversely related. You may have heard someone say, “If I had more time, I would have done it better in ergonomics, this relationship is known as the speed(____) tradeoff that is, slower performance speeds improve (____) and faster speeds cause errors
- In fact, (____)often drops when people perform a job at either a faster or a slower pace than normal
Accuracy
- Since no one performs a task exactly the same way on every occasion, time variance occurs within each person.
- In addition to the (________) within persons, mean times vary between persons.
- The between-person variance of mean performance times is one commonly used measure of individual differences for a class of tasks.
Time Variability
When jobs are easily performed, endurance improves, and fewer rest breaks are needed. Furthermore, when a job is made easier, it is usually safer.
Ease
- Since many people define quality as the measure of successfully meeting customers’ wants and needs, quality is often measured by greater customer satisfaction.
- Other criteria pertaining to the design of production or service systems describe how employees view system operation.
Quality as Critical Criterion
Employed in the form of lower costs, higher revenues, greater net present worth, and greater returns on investments.
Economic
CONTINUED:
He made the point a bit stronger, “What is the point in spending vast sums of money to create the healthiest and safest factory in the country, if the only people who work in it are liquidators?”
Geoffry Simpson
Models of Human Performance
A number of years ago, Harry Helson developed what he called hypotheses, which are really generic models of human behavior and its performance implications
Helson’s Hypothesis
For most variables of concern in ergonomics, performance, as an inverted function of that variable, is U-shaped
The bottom of the U is nearly flat, but the extremes rise almost vertically.
U – Hypothesis
When they see their performance drop below that ____, they provide additional effort.
If performance is above that ____, they withdraw effort.
Par Hypothesis
