dt- human factors and ergonomics

chapter 1

human factors

combination of ergonomics + anthropometrics. aims to:

1. reduce stress/fatigue on people

2. increase ease of use

3. enhance operational comfort

ergonomics

the science of refining the design of a product to optimise them for human use. relationship might be related to:

1. shape, form, colour, texture

2. ease + comfort of use

3. user experience

4. appearance + logic of user

anthropometrics

refers to measurements of the human individual, deals with measurements of size, strength, physical strength. used to determine size of a product

types of ergonomics

1. physical: posture, repetitive stress, movement, occupational health + safety

2. cognitive: mental processes, perception, reasoning, memory

3. organisational: communication, workplace design, teamwork, time management

static anthropometric data

measurements taken when human bodies are in fixed positions, used to inform design for seated or standing tasks.

• much easier to gather as people are still

• skeletal dimensions, static physical measurements, soft tissue measurements

dynamic anthropometric data

measurements taken while a person is in motion, used to inform design for tasks that involve movement such as lifting, reaching, and walking.

• more reliable than static data + more useful

percentile ranges

the proportion of a population with a dimension at/less than a given value (average=50th percentile)

clearance

the minimum space required to allow for movement or access without obstruction.

reach

workspace envelope- the 3D space within which you can carry out physical activities at a fixed location

adjustability

the ability to adjust a piece of equipment to fit individual user needs and preferences, enhancing comfort and effectiveness.

psychological vs physiological factors

psychology: scientific study of mental functions and behaviours

physiology: the study of bodily functions and processes in living organisms.

psychological factor data

human factor data related to physical characteristics used to optimise user safety, health, comfort, and performance

psychological factor data examples

light, smell, sound, taste, texture, temperature

collecting psychological data

1. nominal scales

2. ordinal scales

3. interval scales

4. ratio scales

nominal scales

used for labelling variables, none of them have any numerical significance. e.g. hair colour, gender

ordinal scales

measures of non-numeric concepts such as satisfaction, discomfort. difference between values is not always known

interval scales

numeric scales in which we know not only the order, but also the exact difference between values, e.g. celcius temp thermometer

ratio scales

numeric scales with an absolute zero, allowing for the comparison of absolute magnitudes, e.g. height, weight. (best measurement method)

Human Information Processing Systems (HIPS)

an automatic system that a person uses to interpret information. usually comprised of inputs, processes (can be sensory/central/motor), and outputs

1. input

2. sensory processes

3. central processes

4. motor processes

5. output

breakdown with HIPS

human error e.g.

1. age, skill level

2. people with disabilities

effect of environmental factors (examples)

light, spatial issues, air quality, noise

alertness and perception

1. alertness: the level of vigilance, readiness or caution of an individual

2. perception: the way in which something is regarded, understood, and interpreted

physiological factors: body tolerances

how much the body can withstand, e.g comfort and fatigue. examples:

1. muscle strength in different positions

2. size

3. tolerance to extremes of temperature

4. hand-eye coordination

comfort and fatigue

• comfort: a person’s sense of physical or physiological ease

• fatigue: a person’s sense of tiredness over time

biomechanics

the research + analysis of the mechanics of living organisms. focus on:

1. force

2. duration

3. posute

4. repetition

biomechanics in design

1. muscle strength

2. torque (ability to twist)

3. handle size

4. age of user

5. surface texture