unit 1 human factors and ergonomics

define human factors

a term used for the combination of ergonomics and anthropometrics

what are the aims of human factors

• reduce stress and fatigue to do things faster with less mistakes

• increase safety

• increase ease of use

• enhance operational comfort

• improve system performance, reliability, and maintenance

what are ergonomics

the application of scientific information regarding the relationship of human beings to the design of objects, systems, and environments

what do we mean by physical ergonomics? give an example

it most often deals with work related to the subjects of posture, worksite development, operating layout, repetitive stress and movement, etc. It is the aspect of ergonomics that deals with body measurements such as strength, size. strength and

what do we mean by cognitive ergonomics?

it is concerned with mental processes such as perception, memory, reasoning, and motor responses as they affect interactions among humans and other elements of a system.

What do we mean by the term organizational ergonomics? give an example

it includes communication, work design, shift (work hours) management, teamwork, quality management, etc.

what is anthropometric data?

it is sub-classified as static and dynamic data

what is structural anthropometric data?

aka static data refers to measurements taken while the subject is in a fixed position ex. height. it is easier to gather.

what is functional / dynamic data?

the measurement taken during physical activities, ex. overhead reach.

what tools can be used to collect anthropometric data?

sliding callipers, cloth tape, sitting height meters, and stadiometer

percentiles and percentile ranges

percentiles are shown in anthropometry tables and they tell you whether the measurement given in tables relates to the average person or if someone is below or above average in certain dimensions

what do we mean when we discuss clearance in human factors?

Clearance can be seen as the minimum distance required to enable the user group into or through an area. This is especially important when designing emergency exits and safety hatches.

what is reach

aka workspace envelope, it is the 3D space within which you carry out physical work activities when you are at a fixed position. usually designed for the 5th percentile of the user population, which means 95% of users will be able to reach everything within the envelope.

why does a designer need to consider adjustability when designing seating

certain products tend to be available in diff. sizes / adjustability, therefore this needs to be considered as it has an effect on the design of the legs.

what is meant by the range of sizes VS. adjustability

clothing comes in various sizes as one size cannot be adjusted to fit all but car seats are adjustable to allow for different range of sizes to fit.

what is an argonome and when are they used + advantages and disadvantages

A 2D scaled physical anthropometric model based on a specific percentile of human forms is called an ergonome. They are used with drawings of the same scale as the model to consider the relationships between the size of an object and the people. mainly used for orthographic drawings and modeling.

what is a manikin, and what are the advantages and disadvantages?

It is an anatomical 3D model of the human body. It is used by the artists. It is useful to assess the relationship of body parts to spatial arrangements. They are generally more expensive than ergometers, but they give a better representation of the overall ergonomics.

what is human error

it comes in serval different forms but two important ones are slips and mistakes. slips result from automatic behavior that is intended to satisfy our goals while mistakes results from conscious deliberations.

what are ways of optimizing environmental factors to maximize workplace performance?

• lighting

• thermal comfort

• workspace

• noise

• vibration

what are some perception effects in products?

The principle that explains that the human mind considers objects in their entirety before the perception of their individual parts. This that suggests the whole is seen rather than the sum of parts.

what are physiological factors concerned with

they have to do with bodily tolerances such as comfort and fatugue. when users interact with a product, they may put stress on their bodies.

what is physical ergonomics concerned with

the human anatomy and some of the anthropometric, psychological, and biomechanical characteristics as they relate to physical activity.

what are some human values with types of physiological factors

it considers which activities can be carried out and how human values (ex. quality of life) are enhanced.

what is fatigue

the temporary diminishment of performance. it can be physical or mental fatigue.

what is comfort

the qualitative consideration that informs design decisions and can affect users.

what are biomechanics and what are they concerned with

it includes the research and analysis of muscle, joints, and tendons in the human body. it is used to measure the amount of force put on the muscles and joints of people when working in different positions. it deals with 4 criteria:

• force

• repetition

• duration

• posture

what are some factors affecting muscle strength and human factors

• gender

• age

• pain / physical training

what is cognitive psychology / cognitive ergonomics

it is concerned with mental processes such as perception, memory, reasoning, etc. These affect interactions among humans and others

what are methods of collecting psychological factor data

• observation

• surveys and interviews

• standardized testing

• case studies

what is a nominal data scale

the classification / division of objects into discrete groups where each are identified with a name.

what is an ordinal data scale

the order or position of items where the letters / number / scales are in hierarchal order.

what is an interval data scale

organized into even divisions or interval of equal size without a zero

what is a ratio data scale

organized into even divisions of equal size however there is a true zero.

what are some psychological factor data

• smell

• light

• sound

• taste

• texture

• temperature

• value

what is the human information processing system

it considers the input processes (sensory, central, and motor) and the outputs.

input: generated or received

sensory process: human senses take in info

central process: brain processes info and makes decision

motor process: a physical response

output: action carried out

what are examples of environmental factors

• noise

• temperature

• lighting

• humidity

• hearing

• etc

what is alertness

being aware of what is happening in the vicinity in order to understand how information and one’s own actions affect goals and objectives immediately and in near future. It depends on environmental factors.