Unit 1 - Week 1&2 Flashcards
what are human factors?
- application of psychological science
- designing an environment to fit human limits and capabilities
- designing tools, equipment, processes (they don’t always work out as we might have expected)
Environment includes:
- social, physical, psychological aspects of environment
- items within the space (eg. equipment, tools)
Human limits and capabilites include:
- sensory abilities (eg. visual, auditory perception)
- cognitive processing
- physiological and/or physical abilities
human factors have a strong _ emphasis
engineering
Define Ergonomics (2 points)
- discipline that merges engineering and psychology
- work to reduce fatigue and injury by focusing on the design of the environment
Human factors is an eclectic field that works with and draws from many fields and professions: name 4
- computer science
- architecture
- biological sciences
- medicine
human factors are complentary with I-O: what does this stand for?
industrial-organizational psychology
name 6 elements of I-O, and 3 elements that can also fall under human factors (shared w I-O)
- job analysis
- personnel selection
- training
- performance appraisal/management
- organizational design, change, culture
- leadership
training, personnel selection, organizational design
HF can be a solution to problems for _
special populations
name 4 special populations that can be properly designed for considering HF
- children
- elderly
- people with physical and/or cognitive limitations
- pregnant women
In the example of a walking aid, how might one made for a child differ from one for the elderly
*similar goals in mind but have to think about client’s needs
- height
- wheel size
- colour
- texture
- grip
- type of surface
Name 4 people, 1 type of study, and 1 world event that contributed to human factor advances
- leonardo da vinci
- wright brothers
- alphonse chapanis
- paul m. fitts
- time and motion studies
- ww2
how did leonardo davinci contribute to human factors?
explored anthropometrics and flight
how did the wright brothers contribute to human factors?
pioneered human factors considerations in aviation (using flight patterns in birds to make double decker gliders)
how did ww2 contribute to human factors?
generated 2 critical needs:
Mobilization
Safety and efficiency
define mobilization as a part of the ww2 HF contribution
the need to mobilize and employ vast numbers of men and women made it impractical to select individuals for specific jobs
define safety and efficiency as part of the ww2 HF contribution
the war’s scale required efficient and safe operation of complex systems
how did alphonse chapanis generally contribute to HF?
- one of the fathers of ergonomics and human factors: the science of ensuring that design takes account of human characteristics
what education did alphonse chapanis had?
phd in psychology from yale
which field did Dr. Chapanis specifically help with?
- specifically in the aircraft cockpit
- after a series of crashes, dr. chapanis found that certain cockpit controls were getting confused with others based on their proximity and similarity of shape. He proposed new shapes and layouts that are still in use today
- also worked in bell labs on design of push-button telephones, conducting experiments that led to the present layout of the keys
describe Paul M. Fitts’ background and how he contributed to HF
- phd from university of rochester
- worked at Ohio state university and later at the university of michigan where he developed a model of human movement
- went on to become one of the most highly successful and well studies mathematical models of human motion
*direct application -location of phone buttons close to thumb
what is the Fitts law?
sacrificing speed for accuracy and vice versa
what 2 greek words does ergonomics come from?
Ergon - work
Nomos - law
list the 6 directional interactions in ergonomics
- human with machine
- machine with human
- machine with environment
- environment with machine
- human with environment
- environment with human
give 2 examples of a simple ergosystem
- 1 human interacting with 1 environment around them
- human and machine interacting with environment
give 2 examples of complex ergosystems
- human with access to multiple machines in big environment
- many humans, 1 machine, environment
The scope of ergonomics is _ and is _
extremely wide, not limited to any particular industry or application
how does HF interact with ergonomics?
HF examines the human component of these ergonomics relationships
what’s the full name of the IPO model? (systems theory slide)
- input-process-output model
descrive the IPO model
- input>process>output
- describe the structure of an information processing model
- Inputs
- processes
- outputs
what are inputs?
eg. materials, human resources, money, information
what are processes?
eg. activities, transformations, or operations performed on the inputs
what are outputs?
eg. consumables, services, new info, money
give an example of an input in a cafe scenario
customer enters doors, navigate line, read menu, verbalize order, move to pick up line, grasp cup, add milk, navigate exit door
give an example of processes in a cafe scenario
store line organization, menu displays, employee input order into computer, other employee read/interpret/produce order
give an example of outputs in a cafe scenario
what you are left with (ex. coffee and feeling a certain way)
there is a historical tendency to seek _ of improving system performance and to blame accidents on _
technical means, human error
detailed analyses of accidents and near accidents reveal that_
human error is almost never the sole cause of poor system performance
in HF class activity, after creating the scenario we added 2 things that could go
wrong, possible errors
Bailey (1982) examined what to determine the most important factors of improving system performance and reliability?
the three mile island nuclear incident and aircraft accidents
name the 5 most important factors of improving system performance and reliability (from accidents)
1) design of system components, particularly human-machine interfaces
2) state of the system leading up to the incident (eg. stable/unstable, quiet/busy etc.)
3) Operator’s mental and physical workload
4) work organization (eg. shift system, time during shift, supervision, design of work groups
5) external factors (eg. weather)
to finish the HF class activity, we _
listed 1 more thing that could go wrong/errors with bailey (1982 in mind)
What are anthropometrics?
the data which concerns the dimensions of humans
* designers need to create products that are the right size for the user and comfortable to use
Why should designers be aware of anthropometrics?
- allows designers to accommodate various percentiles of the population so the majority of people can use and interact with the product/service
- designing in public spaces is especially sensitive to these conditions
- no one wants to use or own a product that carries out a task poorly/dangerously
What is a workspace envelope?
a workspace envelope is a 3D space within which you carry out physical work activities when you are in a fixed location
the limits of the workspace envelope are determined by your _
functional arm reach
*also influenced by the direction of reach and the nature of the task (flipping switch is different than gripping something)
what impact does the workspace envelope have on our task arrangement?
tasks should be arranged within this area
what zones is the workspace envelope divided into?
primary, secondary and tertiary zone
What constitues the primary zone of the workspace envelope?
- frequent reaches
- arms bent, windshield motion around you
- 350 mm to front, 450 mm to side
what object belonged in the primary zone during the class activity?
cup
What constitutes the secondary zone of the workspace envelope?
- Infrequent reaches (500 mm to front, 600 mm to side)
what object belonged in the secondary zone during the class activity?
glasses
What constitutes the tertiary zone of the workspace envelope?
- occasional reach
- 700 mm in front
- 720 mm to side
what object belonged in the tertiary zone during the class activity?
- glove
- nails/screws
describe the normal work area and maximum work area in workplace envelope - sitting. What else should we consider?
- the normal work area is within the limits of a comfortable bent arm
- the maximum work area is the area within comfortable reach of the extended arm
*consider potential restraint caused by clothing, age, gender, disabilities, CONSIDER THE TASK
Why might gender be a potential restraint for your work area? (workspace envelope - sitting)
more/less flexibility
Why might age be a potential restraint for your work area? (workspace envelope - sitting)
mobility tends to decrease
Why might clothing be a potential restraint for your work area? (workspace envelope - sitting)
winter thick clothes might be in the way of movement vs lighter clothes, tight clothes might also get in the way
Why do we need to consider the task when thinking about our sitting workplace envelope?
activating a switch requires fingertip measurements
- grasping requires fist closed measurements
*would affect reach
list the principles for seated work
- relaxed upper arms and elbows at 90 degrees to help maintain straight wrists
- adequate clearance for your thighs under the work surface
- small users whose feet do not touch the ground when seated should have a footrest
- for fine work, requiring better visibility, the work surface can be raised, but elbow support must be provided
list the considerations for workspace envelope - standing
- arms are most powerful when the elbows are close to your sides and bent
- for precies, fine work (eg. writing, drawing, reading), the work surface should be higher so that the elbows can be rested on it (this will also bring the work closer to the eyes)
when are the arms and hands most powerful?
when elbows are close to sides and bent
list the principles for standing work
- for work that requires force from the shoulder/back muscles, the work surface should be about 110-250mm lower than the level of the shoulders
- for other tasks that do not require too much force, the surface can be about elbow height or just below
- precision work should primarily be done sitting where the back muscles are supported
- adjustable height work surfaces are best, if this is not possible, design for the largest user, and supply platforms for smaller users
for work that requires force from the shoulder/back muscles, the work surface should be_
about 110-250mm lower than the level of the shoulders
for other tasks that do not require too much force, the surface can be about
elbow height or just below
Vertical reach is limited by
_ (principles for vertical reach)
how far you can reach and grasp objects avobe or below your shoulder height without stretching or bending
vertical reach measurement =
from shoulder to the centre of your closed hand (or extended fingertips to the centre of operation)
how is horizontal reach measured?
the same (as vertical) but in the horizonal plane
vertical reach is often used for _
positioning shelves for storage, handles or controls above head height
name the design examples, measurements to consider and users that your design should accomodate when aiming for EASY REACH design
- vehicle dashboards, shelving
- arm length, shoulder height
- smallest user: 5th percentile
name the design examples, measurements to consider and users that your design should accomodate when aiming for ADEQUATE CLEARANCE TO AVOID UNWANTED CONTACT/TRIPPING design
- service covers, cinema seats
- shoulder or hip width, thigh length
- largest user: 95th percentile
name the design examples, measurements to consider and users that your design should accomodate when aiming for GOOD MATCH BETWEEN USER AND PRODUCT design
- seats, cycle helmets, pushchairs
- knee-floor height, head circumference, weight
- maximum range: 5th-95th percentile
name the design examples, measurements to consider and users that your design should accomodate when aiming for COMFORTABLE AND SAFE POSTURE design
- lawnmowers, monitor positions, worksurface heights
- elbow height, sitting eye height, elbow height (sitting/standing)
- maximum range: 5th to 95th percentile
name the design examples, measurements to consider and users that your design should accomodate when aiming for EASY OPERATION design
- screw bottle tops, door handles, light switches
- grip strength, hand width, height
- smallest or weakest user: 5th percentile
name the design examples, measurements to consider and users that your design should accomodate when aiming to ENSURE THAT AN ITEM CAN’T BE REACHED/OPERATED design
- machine guarding mesh, distance of railings from hazard
- finger width, arm length
- smallest user: 5th percentile, largest user: 95th percentile
What activity did we do on HF and anthropometrics?
object designed by fashion designer vs how you would make it usable
rather than ‘find the person to fit the job…
make the job fit the person
*adjustability: height, reach
what is the aesthetic-usability effect
users often perceive aesthetically pleasing design as a design that is more usable
list the 3 reasons for the aesthetic-usability effect
1) creates a positive response in user’s brain, and may lead them to believe it works better
2) Individuals may be more tolerabt to minor usability issues when the design is pleasing
3) Visually appealing design can mask usability problems and prevent issues from being discovered during usability testing
the aesthetic-usability effect was first explored by_
Kurosu and Kashimura (1995) in their study called “apparent usability” vs “Inherent Usability”
in Kurosu and Kashimura’s research on the aesthetic-usability effect, users consistently rated _ even when _
- visually pleasing designs are more usable
- objective measures of usability did not support this perception
What are the 3 key factors of the aesthetic usability effect?
- first impressions matter
- cognitive ease
- trust and credibility
describe the components of “first impressions matter” as a key factor in the aesthetic-usability effect
- humans are inherently visual creatures
- when we encounter a visually appealing interface, we are more likely to have a positive mindset about it
describe the components of “cognitive ease” as a key factor in the aesthetic-usability effect
- aesthetically pleasing designs often convey simplicity and clarity
- makes the user feel more intuitive, reducing cognitive load required
describe the components of “trust and credibility” as a key factor in the aesthetic-usability effect
- convey a sense of professionalism and competence
- more likely to trust that item and assume the same level of care is applied to its functionality
aesthetics and _ are intertwined
usability
what’s a concequence of ignoring the visual aspect or anthropometrics and the human factor?
a costly oversight
what should be leveraged for successful products and services
aesthetic-usability effect
how is height impacted by human factors/design? (human variability)
- workspaces that are designed for “averages”
- consider adjustability
describe why body type is important (human variability)
height, fitness levels, experiences all impact how humans will interact differently (with) environments and objects
what human variability factors aside from body type can impact our experiences?
- race ethnicity, religion, social groups, socioeconomic status
- our opportunities and/or lack thereof will give us different previous experiences and different perspectives as we interact with environments
describe IQ (and provide full name)
intelligence quotient
- our level of education, or how well someone can use information and logic to solve problems and reason
- impact usability of more complex systems
- designing for ‘general population’ or university populations
we want to design based on _ (aka to accomodate for human variability)
percentiles
our differences bring _
different perceptions
through individual differences, you can see we _differently (3 answers)
think, operate, perceive the world around us
describe the perception-action cycle
- humans learn by doing (not being told). We’re hardwired to learn by interacting with the world around us and then perceiving the results
the perception-action cycle is the circular flow of:
information from the environment>information to our sensory systems>motor output>interacting with environment (and again info from environment)
researchers showed a group of trained dancers + non-dancers in the same dance video (perception-action in a real life athlete example)… what did they do? what did they find?
- measured the brain activity of both groups
- found greater activity in the brain regions associated with movement in the trained dancers group than the non-dancers
Why did researchers find greater activity in the brain regions associated with movement in the trained dancers?
- the dancers had made great use of the perception-action cycle through their dance training, encoded the information required to perform the dance moves
- when they view the video, their brain accessed that information even though they weren’t moving
humans vary in what 5 ways (based on slide)
physically, mentally, personality, knowledge, experiences
- physical differences
- vision, hearing, manual dexterity, colour vision or visual acuity
- different personalities, which can make a differences in the type of work they are best suited to do, impact on safety requirements
- different knowledge and experience to draw on
name 5 physical differences in which humans vary
body shapes, height, weight, strength, capabilities
