human factors
the practice of designing products, systems and processes to take account of the interaction between them and the people that use them
Ergonomics
the science of refining the design of products to optimise them for human use
Factors that affect human factor and ergonomics
- Anthropometric
- Psychological factors
- Physiological factors
Aim of human factors and ergonomics in design
- Reduce stress and fatigue on people
- Increase safety for people
- Increase ease of use of a product
- Improve system performance, reliability and maintenance
Anthropometrics
is the study of the sizes of humans, their body parts and also the relative proportions of the different body parts to each other
Anthropometrics data for a chair
- Popliteal height
- back height
- length of waist
- length from back to knee
PHYSIOLOGICAL FACTORS
- concerned with human sensory perceptions during the use of a products. It also affects operations including those that impact operations including environment conditions
- *considers the importance of biometrics in the design of different products
- it also considers the impact of designs on human organ systems, in the design of products
ANTHOPOMETRICS DATA
- STATIC DATA
- measurements taken while the subject is in a field or standard position Eg. Height, arm length - DYNAMIC DATA
- data obtained when the subject is moving, difficult to obtain Eg. Reach arcs, reaction time, muscle strength
STADIOMETER
> to measure standing height
> infant measuring table for height of babies (infanometer)
SITTING HEIGHT TABLE
> measures the distance from the crown of the head to the rump
HAND DYNAMO METER
> grip strength
SKINFOLD CALIPERS
> measure the amount of subcutaneous fat by pinching a part of the body
> standardised parts for testing
- Triceps
- Sub-scapular skinfold
SPREADING CALIPERS
> used for measurements of head and face
Difficulties in collecting anthropometric data
> incorrect calibration of tools
> training and consistency of personnel collecting data
> time of day - you could be up to 1-2 cm shorter at night due to cartilage compression
> variable subject body shapes
> inaccuracies due to subjects not following instructions
Primary vs secondary data
PRIMARY DATA
- obtained directly by the designer who collects anthropometrics measurements from the group concerned
SECONDARY DATA
- involves summary, coalition and synthesis of existing data
CLEARANCE
> physical space between two objects or minimum distance required to enable user group into an area
Advantages and disadvantages of primary compared to secondary
ADVANTAGES
- can get specific customised data
- data will be up to date
- certain about the reliability of the information
DISADVANTAGES
- time consuming to carry out
- costly and needs manpower
- profile suer group many not always be available
- designer needs to have good data collection resources and analysis skills
REACH
> a range that a person can reach or grasp from a certain position
ADJUSTABILITY
> the ability of the dimensions of a product to be changed in size
> used to increase the range of percentiles that a product is appropriate for
*
work space envelope
it is a 3D space within which you carry out physical work activities when you are at a fixed location*
RANGE OF SIZES vs ADJUSTABILITY
> some products come in a range of sizes to cater to different groups in the population
> some products are designed for adjustability
> adjustability is obtained through one of these methods:
- Mechanical
- Electrical
- Pneumatic
- Hydraulic
-
Physiological factors6
-
Psychological factors13
-
Anthropometrics21
-
resources and reserves11
-
waste mitigation strategies16
-
energy utilization, storage and distribution24
-
green design7
-
eco design13
-
conceptual modelling8
-
graphical modelling9
-
physical modelling7
-
computer aided design21
-
rapid prototyping2
