1. Human Factors and Ergonomics

anthropometric data

the measurements of the human body, height, weight, arm length, etc…

ergonomics

a science that studies how people interact with things and how to design things better for people’s comfort and the system’s performance

ergonomic primary and secondary data

primary data: you get the information yourself. You go gather the data. Sample is always small from 100-1000 max
secondary data: typically comes from the data made by the agencies and have a relatively large sample size

static measurement

measurements of length between points on a body

dynamic measurement

measurements of reach, movement, or strength. Would be used to determine how a person moves in a space (ex. a lever from a seated position)

reach

how far a person can reach (usually from a seated position). There is a normal reach and a maximum reach

percentile and percentile ranges

designers have to think of which percentile they are designing for. Using averages do not work.

percentile

a point where a certain percentage of people are below/smaller than a given size (ex. men under 6feet)

factors affecting anthropometric measurement (age, gender, ethnicity, etc)

who you’re designing for: children, adults
which measurements are relevant: static, dynamic, reach, etc
which percentile you need to design for: 50th or extremes

the human information processing system

a research done on how people receive information

human information processing process

input: it is generated or received
sensory process: human senses take in information
central processes: the brain processes the information and makes decisions
motor processes: a physical response
output: the action carried out

use human information processing process to process biking

input: travelling
sensory process: road/wind/cars
central processes: understand the environment
motor processes: you move
output: travelling

factors affecting the processing of information

• age

• strength

• skills (ex. not able to use a mountain bike)

• health

psychological factor data

sight: aesthetics, contrast,…
hearing: volume, pitch, …
touch: texture, grip, …
taste: toxicity, safety on teeth
smell: aroma, odor

collecting data: nominal

by name

collecting data: ordinal

by order

collecting data: interval

by giving it a name, put it in an order, and divide how far away each scale is from another. (ex. temperature is relative in celsius)

collecting data: ratio

height, weight, richter scale. can accommodate absolute zero

what is an example of collecting data using the different types? (car)

we can use these scales to measure people’s preferences about a car (ordinal scale), it’s fuel efficiency (ratio scale) and it’s size category (nominal scale)

absolute zero

you can have something that is worth nothing

environmental factors

comfort: age and gender can mean that people respond to the environment differently, it also can include size. (ex. don’t make something for Asia and bring it to the Netherlands, 2 different heights)

alertness

the ability to be focused and awake

what does alertness dependent on?

• temperature

• sound

• lighting

• air quality

• smell

physiological factors

• muscle strength

• endurance

• visual acuity (how well you can see/make out colors)

• tolerance

• range of frequencies

• hand/eye coordination

comfort and fatigue

• comfort

• adjustability (height, softness)

• pleasure

fatigue

injuries can happen because of fatigue, think about the impact a product being used over time. Rick factors include:

lighting heavy things

bending

reaching

pushing and pulling

bad posture

repetitive actions

performance

designers should think about fatigue and let the user work with them for as along as possible

health and safety

fatigued user will more likely injure themselves

causes of MSD (muscular skeletal distress)

• awkward postures

• sitting still

• force (moving things)

• repetitive movements

• vibrations

symptoms of MSD

• swelling

• pain and discomfort

• stiffness and range of motion

• inability to perform functions and duties

what are biomechanics?

movement of the body + the study of bones and muscles

how is biomechanics studies? what do they focus on?

• force: how much force is needed to move, turn, etc

• repetition: how often are people going to repeat the movement

• posture: if product is large, how will it affect their posture

• duration: how long are we using the product for? how often?