IB Design and Technology
Standard Level
Topic 1
Human Factors and Ergonomics
Topics
1.1a Anthropometrics
1.1b Psychological factors
1.1c Physiological factors
Essential Idea: Designers consider three human factors to ensure products meet ergonomic needs.
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The word “ergonomics” is derived from the Greek words ‘ergon” (work( and ‘nomos’ (law). In the U.S the term human factors is
often used.
Ergonomics is about designing for people, wherever they interact with products, systems or processes. We usually don’t notice
good design (unless perhaps, it’s exceptional) because it gives us no cause to, but we do notice poor design.
http://www.kkstudio.gr/#the-uncomfortable
Look at the link above. choose three products. Sketch them and explain what makes them unsuitable for ergonomic needs.
The artist has deliberately designed products that are impossible to use like the one below.
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1.1a Anthropometrics- theoretical knowledge
Design is human centred and, therefore, designers need to ensure that the products they design are the right size for the user and
therefore are comfortable to use. Designers have access to data and drawings, which state measurements of human beings of all
ages and sizes. Designers need to consider how users will interact with the product or service. Use and misuse is an important
consideration
1.5 Design is human centred and focuses on the needs, wants and limitations of the end user
1.18 Designers must consider how users will interact with, use and misuse the products they design
1.20 Design Permeates every aspect of human experience. Individuals make design decisions in all areas of their work, home and
leisure.
International Mindedness- A wide selection of anthropometric data is published and regionalised, for example, Asian data v
European data. The designer must work with data appropriate to the target market
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Task
Look at the information in The Measure of Man and Woman on pages 25 and 26 (computer stations). What parts of the
computer stations design is considered as human centered and why?
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Task
How is the data represented in The Measure of Man and Woman to enable the designer to design and create products and
environments that are suitable for a range of target markets?
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Anthropometric Data: The measurement and collection of data concerning the different
sizes of men, women and children.
Anthropometric data is more than a simple measurement, it can be sub-classified
as
Static Data (also known as Structural data)…...this refers to measurements taken
while while the subject is in a fixed or standard position, e.g. height, arm length
Dynamic Data (also known as Functional data)…..this refers to measurements
taken during physical activities, e.g. crawling height, overhead reach and a range
of upper body movements.
Why static data is is much easier to gather than dynamic data?
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User Populations
It is important to consider the intended User Population for any product (or system) you are
designing. It can be defined as the range of users for a particular product or system. These can be
defined by age, gender, physical condition, socio-economic class etc.
Population Stereotypes
Population stereotypes: responses that are found to be widespread in a user population. “Longterm habits and well-ingrained knowledge that we have about the world” (Kantowitz & Sorkin,
1983).
When walking into a room, assuming it is dark, what way would you flip a toggle switch to turn the lights on? You have two
choices, up flip or down flip.
Indeed, most Americans think that up is on but in other countries, the opposite is true.
Making use of population stereotypes in the design of the controls for products is relevant. It is usually anti clockwise for ‘on’
when dealing with fluids and gases (a tap) and clockwise for ‘on’ when dealing with mechanical products (a radio). Population
stereotypes can be displaced (changed or relearned) by alternative learnt responses, but they frequently reassert (return) under
conditions of stress such as tiredness or panic.
Why is this concept dangerous?
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Give one example of population stereotypes that you have discussed in class
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Collecting Anthropometric Data
The actual data is collected using a range of different tools, sliding calipers, skinfold calipers, fabric tapes and stadiometers.
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Percentiles
When data has been collected and placed into a
table for analysis, it is almost always going to
look like the graph shown. The graph below
shows the height of a group of adults.
First, notice that the graph is symmetrical – so
that 50% of people are of average height or
taller, and 50% are of average height or smaller.
The graph tails off to either end, because fewer
people are extremely tall or very short. To the
left of the average, there is a point known as
the 5th percentile, because 5% of the people
(or 1 person in 20) is shorter than this particular
height. The same distance to the right is a point known as the 95th percentile, where only 1 person in 20 is taller than this height.
So, we also need to know whether we are designing for all potential users or just the ones of above or below average
dimensions. Now, this depends on exactly what it is that we are designing.
How are percentiles used?
Referring back to the graph on the previous page. Let's say the adult population makes up 100%, researchers break down the
group into 100 percentile groups with the first percentile being the smallest and the 100th
percentile being the largest. As designers, most of the time, it suffices to limit ourselves to
dealing with the 5th to the 95th percentile, meaning that we would cover 90 out of 100 adults.
A constant problem for designers is the conflict between designing for as wide variety of
people as possible, and, at the same time, helping the manufacturer to keep the production
costs down.
For example, if we were designing a doorway using the height, shoulder width, hip width etc.,
of an average person, and then half the people using the doorway would be taller than the
average, and half would be wider.
Since the tallest people are not necessarily the widest, more than half the users would have to
bend down or turn sideways to get through the doorway. Therefore, in this case we would
need to design using dimensions of the widest and tallest people to ensure that everyone
could walk through normally.
Deciding whether to use the 5th, 50th or 95th percentile value depends on what you are
designing and who you are designing it for.
Usually, you will find that if you pick the appropriate percentile, 95% of people will be able to
use your design. For instance, if you were choosing a door height, you would choose the dimension of people's height (often
called 'stature' in anthropometry tables) and pick the 95th percentile value – in other words, you would design for the taller
people. You wouldn't need to worry about the average height people, or the 5 th percentile ones – they would be able to fit
through the door anyway.
At the other end of the scale, if you were designing an aeroplane cockpit,
and needed to make sure everyone could reach a particular control, you
would choose 5th percentile arm length – because the people with the
short arms are the ones who are most challenging to design for. If they
could reach the control, everyone else (with longer arms) would be able to.
This should also reinforce the requirement to ensure users can safely
interact with their environments.
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Tasks
2. Give an example of products for each of the given percentiles and explain why that percentile would be used. Use the
information on the link below to help.
http://www.ergonomics4schools.com/lzone/anthropometry.htm
5th Percentile
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50th Percentile
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95th Percentile
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Task
For this task you need to work with a partner from a different ethnic group to yourself (if possible).
Your task is to design train bench seating for those two groups
Find relevant examples of regionalized anthropometric data for yourself and your partner.
Decide which measurements are relevant in the design of the train seat below.
Which percentile range will you use and why?
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How might the measurements differ for your two ethnic groups and why? Add measurements to the two diagrams below.
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What problems may a train passenger travelling outside of their home country have when using the train seat?
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Add your own dimensions. What do you notice about them?
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Ethnic group 1
Ethnic group 2
Primary and Secondary Anthropometric Data
As this suggests, there are 2 forms of info. There are many
secondary sources of anthropometric data available, both
in print and online. This is probably where most of your
data will come from. However, if you have a particular
client or access to the user population you wish to design
for, you may wish to collect measurements yourself and
generate your own primary data.
As mentioned in the first slide, it is important to consider
the reliability of the data you are using or generating. For
secondary sources, is it appropriate in terms of age, gender,
race or geographic region?
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If it is primary data, consider the conditions under which it was collected, were the subjects wearing bulky clothing, or gloves? If
it was a part particularly hot/cold day, the measurements collected may not be that reliable.
Question
How could you make sure that the data collected is reliable? What limitations might this have?
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Range of Size and Adjustability
Certain products tend to be available in different sizes or with adjustability built in as there really is no ‘one size fits all’. Consider
the following examples:
Clothing comes in a range of sizes. For manufacturers to make clothing fit every individual variance would not be economically
possible, thus it tends to come in a range of sizes based on percentile ranges.
Adjustability
Ironing tables can be adjusted to allow for people of a different height to use comfortably.
This has an effect on the design of the legs, as this is how the board is adjusted in height. What
design features allow for the ironing board to be adjusted?
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Children’s car seats are adjustable to allow for a range
of sizes and a growing child.
As are other items in a car, such as adjustable seat
backs, adjustable leg room, adjustable seat belts,
adjustable steering wheels, adjustable mirrors,
adjustable headrest, etc.
Task
What 2 types of clothing do designers design to ensure that they fit a wider range of users? Sketch two examples and label the
design features used
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Percentile Ranges
Which user population and percentile ranges would be required for the following products? Are all of the measurements
necessary?
Childs Car Seat
User population _____________________________________
Percentile ranges
Sitting height:
Leg room:
Arm reach:
Viewing angles:
Hip breadth:
Thigh length:
Office Chair
User population ________________________
Sitting height:
Leg room:
Arm reach:
Viewing angles:
Hip breadth:
Thigh length:
Task
Work in pairs. Look at the anthropometric dimensions in “The Measure of Man and Woman” ( Drawing page 11,12). Your
teacher will ask you to compare your measurements to those in the charts. What do you notice about your dimensions?
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Clearance, Reach and Adjustability
Clearance
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Sometimes people or machines
have to move through or work in
restricted areas, for example,
maintenance work. 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
Reach-The workspace envelope.
A 'workspace envelope' is a 3-dimensional space within which you carry out physical work activities when you are at a fixed
location. The limits of the envelope are determined by your functional arm reach which, in turn, is influenced by the direction of
reach and the nature of the task being performed. Most of the things that you need to use to carry out your tasks should be
arranged within this area. Workspace envelopes should be designed for the 5th percentile of the user population, which means
that 95% of users will be able to reach everything placed within the envelope.
http://www.ergonomics4schools.com/lzone/workspace.htm
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Task
Using the ergonomics4schools website, calculate the workspace envelope needed for using a computer workstation and working
in a kitchen.
Computer workstation envelope dimensions
Kitchen dimensions
Examples
What are aiming for with your
design?
Design examples:
Examples of measurements
to consider:
Users that your design should
accommodate:
Easy reach
Vehicle dashboards, Shelving
Arm length, Shoulder height
Smallest user: 5th percentile
Adequate clearance to avoid
unwanted contact or trapping
Service Covers, Cinema seats
Shoulder or hip width, Thigh
length
Largest user: 95th percentile
A good match between the user
and the product
Seats,
Knee-floor height, Head
circumference, Weight
Maximum range: 5th to
95th percentile
Elbow height, Sitting eye
height,
Maximum range: 5th to
95th percentile
Cycle helmets, Pushchairs
A comfortable and safe posture
Lawnmowers, Monitor
positions, Worksurface heights
Elbow height (sitting or
standing?)
Easy operation
Screw bottle tops, Door
handles, Light switches
Grip strength, Hand width,
Height
Smallest or weakest user: 5th
percentile
To ensure that an item can't be
reached or operated
Machine guarding mesh,
Finger width
Smallest user: 5th percentile
Distance of railings from
Arm length
Largest user: 95th percentile
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hazard
Anthropometrics Teacher Directed Activity
Textiles
Anthropometric data sets can vary significantly between populations. Particularly in the fashion industry, the variance in these
data sets impacts the size range of clothes for particular markets.
http://jezebel.com/5284796/plus-vs-petite-why-retailers-find-it-hard-making-clothes-to-fit-most-women
Look at the issues on the website
Graphics and Product design ( thanks to Technology student.com for this activity)
http://www.hermanmiller.com/products/seating/lounge-seating/eames-lounge-chair-and-ottoman.html
The classic chair seen below, was designed by Charles and Ray Eames in the 1950s. It was first manufactured for
sale in 1956 by the Herman Miller Furniture Company of Michigan, USA. The angle of recline cannot be adjusted,
as it is set in one position permanently.
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1. Explain in detail, how and why you think anthropometric data / information was collected and considered
during the research and design of the chair.
2. Explain how you think the anthropometric data / information was then applied ergonomically to the chair.
You may wish to read the reference sheet (below the diagrams), which is guide as to how to answer this
question.
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Ergonomics is all around you. Consider...
the toothbrush you used this morning
the transport you took to get here
the shoes you’re wearing
the chair you sit on at school or work
the computer you work on
the kettl you boil in your kitchen
the mobile phone you text on
1.1b Psychological factors
Nature of Design:
Human beings vary psychologically in complex ways. Any attempt by designers to classify people into groups merely results in a
statement of broad principles that may or may not be relevant to the individual. Design permeates every aspect of human
experience and data pertaining to what cannot be seen such as touch, taste, and smell are often expressions of opinion rather
than checkable fact.
Concepts and principles:
● Psychological factor data
● Human information processing systems
● Effect of environmental factors
● Alertness
● Perception
Guidance:
● Data in relation to light, smell, sound, taste, temperature and texture as qualitative or quantitative (ordinal/interval)
● Methods of collecting psychological factor data
● Representing the human information processing system using flow diagrams
● Applying the human information processing system to a common task
● Evaluating effects and reasons for breakdown in the human information processing system
● User responses to environmental factors
● How environmental factors induce different levels of alertness
● The importance of optimizing environmental factors to maximize workplace performance
● Assessing the impact of perception in relation to the accuracy and reliability of psychological factor data
Links and resourses
http://www.digitalartsonline.co.uk/features/graphic-design/psychology-of-design-explained/
http://youtu.be/1KEse_x1Sko
http://www.slideshare.net/Applied_Cognitive/hs-2013-what-is-human-factors?qid=65a0edb7-f8dc-4c8d-b4d6-2828bc82f1a3&v=default&b=&from_search=12
http://www.io.tudelft.nl/fileadmin/Faculteit/IO/Onderzoek/Publicaties/Top_wetenschappelijke_publicaties/top10_-1/Top_10-1_Abstracts_en_Lijst__oud_van_IO_Campus/doc/Schiffersteinsplitmodality.pdf
Human error & Human Information processing
http://nas.psych.uidaho.edu/~ad.uidaho.edu%5Cbdyre/psyc562/readings/Human_Reliability_and_Error/Sharit(2006).pdf
http://www.hfes.org/Web/EducationalResources/textbooksmain.html
http://psychtoolbox.org/HomePage
http://www.merlot.org/
●
http://hsi.arc.nasa.gov/index.php
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http://hsi.arc.nasa.gov/web/humanfactors101/index.html
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complete these lessons from NASA
http://baddesigns.com/
http://www.ergonomics.org.uk/
Human Factors
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http://youtu.be/bSK-Z6UZsIM
http://quizlet.com/6128108/option-e-human-factors-design-flash-cards/
Pedestrian urbanisation - Human Factors
http://trid.trb.org/view.aspx?id=114653
book: Human Error
http://www.google.com.hk/books?hl=en&lr=&id=CT_wFPljJEC&oi=fnd&pg=PR17&dq=human+factors+Psychological+factors&ots=SqD8UVqcwP&sig=FosbtPtezUQyiWuuhPWjJylmAFg&redir_esc=y#v=onepage&q=human
%20factors%20Psychological%20factors&f=false
PDF Copy
http://nas.psych.uidaho.edu/~ad.uidaho.edu%5Cbdyre/psyc562/readings/Human_Reliability_and_Error/Sharit(2006).pdf
4 pleasures
http://www.google.com.hk/books?hl=en&lr=&id=0s3el8sDjHsC&oi=fnd&pg=PR6&dq=human+factors+Psychological+factors&ots=jEwHfTU_iA&sig=TQqwKzi2W
OCQH-yBBdRwUN9qFyw&redir_esc=y#v=onepage&q=human%20factors%20Psychological%20factors&f=false
Psychological factor data
Write a definition of what is meant by psychological human factors
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Cognitive psychology / cognitive ergonomics is concerned with mental processes, such as perception, memory, reasoning, and
motor response, as they affect interactions among humans and other elements of a system.
In their everyday practical work ergonomists may well be more interested in improving what people do rather than what people
know or feel. However an enduring improvement of performance seems to be possible only if the underlying cognitive
representations as well as attitudes and competences of participating persons are known. This is why, the Chomskian distinction
between competence and performance become very important for cognitive ergonomists (Amalberti, 2001).
We want to feel pleasure when we use products. Good design creates an emotional interaction between product and user
The “four pleasure framework” was identified by Professor Lionel Tiger from Rutgers University in New Jersey, US. It includes the
four areas of physio-pleasure, psycho-pleasure, socio-pleasure and ideo-pleasure.
Note- You will study this in more detail in higher topic 7- User centered design.
Physio-pleasure can be derived from the feel of a product during use, (for example, wearing a silk garment or the smooth feel of
an iPod), its taste (for example, from eating chocolate) or its smell, the smell of leather, a new car, coffee, fresh bread from a
bread-making machine
Socio- pleasure
Products and services can facilitate social interaction in a number of ways. E-mail, Internet and mobile phones, for example,
facilitate communication between people. Other products may promote social interaction by being conversation starters, for
example, jewelry, artwork or furniture. Clothing can communicate social identity and indicate that a person belongs to a
particular social group.
Psycho-pleasure
In the case of products, this includes issues relating to the cognitive demands of using the product or service and the emotional
reactions engendered through the experience of using it. For example, it might be expected that a Smart Phone is better than
they expected.
Ideo-pleasure
Products that are aesthetically pleasing can be a source of ideo-pleasure through appealing to the consumer’s tastes. Values
could be philosophical or religious or may relate to some particular issue such as the environment or a political movement.
These values can be embodied in products. For example, a product made from biodegradable materials might be seen as
embodying the value of environmental responsibility.
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Task- How are the
products below examples of
Tigers concepts? Which one
of the four pleasures are
they satisfying and why?
Human Factors Psychology
What Makes Human Factors Psychology Different?
Human factors psychology is generally very applied, with most employed in this area working directly in the field. Psychologists
working in human factors spend much of their time performing research and applying what they know about human behavior,
perception, and cognition to create more usable products and work environments.
http://www.jnd.org/
Don Norman is an academic in the field of cognitive science, design and usability engineering and a co-founder and consultant
with the Nielsen Norman Group. He is the author of the books The Design of Everyday Things and Living with Complexity.
Much of Norman's work involves the advocacy of user-centered design.[1] His books all have the underlying purpose of
furthering the field of design, from doors to computers. Norman has recently taken a controversial stance in saying that the
design research community has had little impact in the innovation of products, and that whereas academics can help in refining
existing products, it is technologists that accomplish the breakthroughs. [2]
Below is a great video where he discusses emotion and design.
Watch the two videos below. Then
Explain what is meant by psychological human
factors
http://www.ted.com/talks/don_norman_on_
design_and_emotion (12 minutes)
http://labs.ideo.com/2011/09/08/musicalstaircase/
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Psychological factor data
Data in relation to light, smell, sound and taste, temperature and texture as qualitative or
quantitative (ordinal/interval) Methods of collecting psychological factor data
Ergonomists collect data in relation to a range of psychological human factors.
Complete the table below and explain the most relevant psychological factors
Product
Psychological
Explanation
Human factors
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Task- perceived data
Hold a coin and a tissue to your cheek. Which one feels cooler and why?
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Temperature
Discussion point
What do you think about the temperature in this room? Why is Mrs. Ford wearing a jacket? Why are you wearing a thin shirt?
The temperature is not different where you are sitting.
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http://www.youtube.com/watch?v=vWTdCCFpzWs
Watch the video above
Describe what thermal comfort is using the link below. What are the six factors that contribute to thermal com
http://www.hse.gov.uk/temperature/thermal/factors.htm
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Below are four examples of psychological factors
Light
Smell
Sound
Taste
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Task
Give examples of products where the factors above are important. Sketch each product
Specializations within Human Factors Psychology
● Human-computer interaction
● Cognitive ergonomics
● Usability
● User experience engineering
● Product design
● Error prevention
Important Topics in Human Factors Psychology
● Cognition
● Perception
● Educational technology
● Graphic design
● Instructional message design
● Human capabilities and limitations in specific work
● The use of virtual reality in employee training
Problems that may arise from collecting this type of data is that people’s perception can differ and often it can give inaccurate
results. Also it does not take into account adverse or stressful situations and population stereotypes.
There are 4 main scales used when collecting ergonomic data:
● Nominal
● Ordinal
● Interval
● Ratio data scales
Experiments need data. To get data, a researcher must measure something. Measurements come in many different varieties.
For example, it is possible to measure time, weight, length, number of responses, height, pleasantness and brightness. The way
numbers represent a particular measurement is called the "scale" (scales of measurement).
Nominal Scale
A nominal scale classifies data according to a category only. For example, an experiment may examine which color people select.
No assumptions are made that any color has more or less value than any other color. Colors differ qualitatively from one
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another, but they do not differ quantitatively. A number could be assigned to each color, but it would not have any value. The
number serves only to identify the colour.
Example
Ordinal scale
An ordinal scale classifies data according to rank. With ordinal data, it is fair to say that one response is greater or less than
another. For example, if people were asked to rate the hotness of three chili peppers, a scale of "hot", "hotter" and "hottest"
could be used. Values of "1" for "hot", "2" for "hotter" and "3" for "hottest" could be assigned. However, and this is important,
you cannot say that the difference between the hot pepper and the hotter pepper is the same as the difference between the
hotter pepper and the hottest pepper. It may be that you can eat a hot pepper without feeling any pain. You may also be able to
eat the hotter pepper, but your mouth just tingles a bit. However, the hottest pepper is really, really hot...so hot your whole
mouth burns.
Interval Scale
An interval scale assumes that the measurements are made in equal units. However, an interval scale does not have to have a
true zero. Good examples of interval scales are the Fahrenheit and Celsius temperature scales. A temperature of "zero" does not
mean that there is no temperature...it is just an arbitrary zero point.
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Ratio Scale
The difference between a ratio scale and an interval scale is that the zero point on an interval scale is some arbitrarily agreed
value, whereas on a ratio scale it is a true zero. For example, 0°C has been defined arbitrarily as the freezing temperature of
water, whereas 0 grams is a true zero, that is, no mass. Ratio scales are similar to interval scales. A ratio scale allows you to
compare differences between numbers.
For example, if you measured the time it takes 3 people to run a race, their times may be 10 seconds (Racer A), 15 seconds
(Racer B) and 20 seconds (Racer C). You can say with accuracy, that it took Racer C twice as long as Racer A. Unlike the interval
scale, the ratio scale has a true zero value.
http://psychology.ucdavis.edu/faculty_sites/sommerb/sommerdemo/scaling/levels.htm
Give examples of collecting of data using each of the data scales above in relation to the psychological factors of Light Smell
Sound and Taste
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Methods of collecting psychological factor data
Qualitative psychological research is where the research findings are not arrived at by statistical or other quantitative
procedures. Quantitative psychological research is where the research findings result from mathematical modeling and
statistical estimation or statistical inference. Since qualitative information can be handled as such statistically, the distinction
relates to method, rather than the topic studied.
Task- There are many ways of collecting psychological human factors data. Chose the most relevant from the list on the link
below and explain how they are conducted
http://en.wikipedia.org/wiki/Human_factors_and_ergonomics http://youtu.be/UPCItrMUNXY
1. Human performance data collection
http://youtu.be/zWmH2IGK--s
2. Sampling
http://youtu.be/F8EyAoPyFKI
http://youtu.be/C1FQf3Rpu4c
4. Collecting human factors data
http://www.youtube.com/watch?v=bSK-Z6UZsIM&feature=youtu.be
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3. Collecting , interpreting and analyzing data slideshare:
http://www.slideshare.net/manojrkasare/human-factors-topic-1-introduction?qid=65a0edb7-f8dc-4c8d-b4d62828bc82f1a3&v=default&b=&from_search=7
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Human information processing systems
Representing the human information processing system using flow diagrams
When understanding how humans process information it can be useful to represent this as a flow diagram.
The arrows represent the flow of information through the system. The boxes represent functional elements in the processing
chain, where information is processed, these are the
motor processes.
Look at the diagram to the right and explain it
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Applying the human information processing system to a common task- making a phone
call
The arrows represent the flow of information through the system. The boxes represent functional elements in the processing
chain, where information is processed:
Task
Explain the process of using a mobile phone to make a call
Evaluating effects and reasons for a breakdown in the human information processing system
Information may be incorrect or no suitable responses to it are available. The motor output stage may be unable to perform the
actions specified by the central processing unit. Explain how the human information processing system may break down at each
stage of the example above
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Young children and elderly, infirm or disabled people can encounter a range of problems which are highlighted by some
examples shown below taken from this website:
http://www.baddesigns.com/
Design issue 1
The lids on oatmeal containers were recently redesigned. The new style
lid fits down into the top of the oatmeal container. There's a lip all the
way around the inside of the lid (arrow). The lip, which looks like it could
work as a handle, affords sliding one's fingers underneath to pick up the
oatmeal container. The other day I reached into the pantry to grab the
oatmeal. I put my fingers under the lip of the lid using my thumb to hold
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the side on the container the lids on an oatmeal container. I got just a few steps from the pantry before the lid came off
dumping oatmeal all over the floor! The problem is that it looks like you can pick up the container by the lid, but you can't.
Maybe the purpose of this new lid is to get people to buy more oatmeal, since half of it ends up on the floor! The old-style lid
doesn't look like you could use it as a handle to pick up the oatmeal container, so people probably aren't inclined try it. People
are probably more apt to use two hands to pick up containers with these
old-style lids.
Design suggestion
The lid on the new-style container should not look like it could work as a
"handle" to pick up the container. This might be done by: Not making the
center of the lid set down in the top of the container so deeply. Removing
the "handle" from the inside of the lid by curving the lip outward rather
than inward.
Design issue 2
Why might you have trouble with this tap? The owner repeatedly find himself turning
these cross-shaped handles the wrong way. So instead of turning the water off, he ends
up turning it on full blast. Analyze this tap and figure out the problem.
The main problem is that the cold water handle opens clockwise, whereas the hot
water handle opens counter-clockwise. Traditionally, faucets with these cross-shaped
handles, both hot and cold, always open counter-clockwise. As the saying goes, "lefty
loosely, right tightly". Like a screw, you turn left to loosen and right to tighten. Think of
the number of things you use everyday, such as jars, bottles and caps of toothpaste
tubes, which follow this same principle! Thus, the way the cold-water handle opens is
unexpected and causes mistakes.
Why is the tap designed like this? During a trip to the local hardware store it
was found that manufacturers have designed one basic tap that is sold with
two different handles: cross-shaped handles and lever handles, like the
faucets pictured here. They probably do this to save money. Apparently, some
people prefer the way the cross-shaped handles look and some prefer the
lever handles. The lever handles, shown in this picture work well with the way
the faucet opens. You expect the right lever handle to open clockwise and the
left handle to open counter-clockwise (as shown).
People expect familiar controls like cross-shaped faucet handles to work in a
certain way (to open counter-clockwise). When they don't work in the expected way, people have problems. Manufacturers
must consider people's expectations. Therefore, when the cross-handles are used, the faucet should be equipped with a cold
water valve that opens counter-clockwise. When the lever handles are used, the cold
water valve should open clockwise
Design issue 3
This picture shows a dirt path worn across the grass on a university campus. Notice how
the path is in the most convenient place to walk relative to the crosswalk painted on the
street and the dip in the curb. It looks like there should be a sidewalk here, but someone
forgot to put it in. Instead of putting in a sidewalk, someone put in a sign to try to tell
people not to walk on the grass.
Here is a close-up picture of the "Keep off the grass" sign! Do you think this sign is really
going to work?
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Design suggestion
Take a hint from people's behavior. If they find it convenient to walk in a
particular place, put in a sidewalk, not a barrier. This is an example of
"natural" design.
http://www.baddesigns.com/
Task
Select another issue from the website above and explain the possible solution outlined
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Sketch the issue and the solution in the space below and over the page
Alertness
Fatigue, stress, temperature and noise levels have a significant impact on alertness. Long repetitive task may often lead to a lack
of concentration and errors/accidents may occur. Dangerous or very stressful situations can also affect people’s judgments.
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Task
Think of an example of a situation where you may not have been alert as you should have been. What factors lead to this and
how could you have solved them. Could this situation been dangerous? How?
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Situation awareness
This is the perception of environmental elements with respect to time and/or space, the comprehension of their meaning, and
the projection of their status after some variable has changed, such as time, or some other variable, such as a predetermined
event. It is also a field of study concerned with perception of the environment critical to decision-makers in complex, dynamic
areas from aviation, air traffic control, ship navigation, power plant operations, military command and control, and emergency
services such as fire fighting and policing; to more ordinary but nevertheless complex tasks such as driving an automobile or
bicycle.
This involves being aware of what is happening in the vicinity, in order to understand how information, events, and one's own
actions will impact goals and objectives, both immediately and in the near future. One with an adept sense of situation
awareness generally has a high degree of knowledge with respect to inputs and outputs of a system, i.e. an innate "feel" for
situations, people, and events that play out due to variables the subject can control. Lacking or inadequate situation awareness
has been identified as one of the primary factors in accidents attributed to human error. Thus, situation awareness is especially
important in work domains where the information flow can be quite high and poor decisions may lead to serious consequences
(e.g., piloting an airplane, functioning as a soldier, or treating critically ill or injured patients).
Having complete, accurate and up-to-the-minute SA is essential where technological and situational complexity on the human
decision-maker is a concern. Situation awareness has been recognized as a critical, yet often elusive, foundation for successful
decision-making across a broad range of complex and dynamic systems, including aviation, air traffic control, ship navigation
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healthcare, emergency response and military command and control operations, and offshore oil and nuclear power plant
management.
Task
Read the information above. Use the same headings as the diagram above. Select a task and analyse the issues associated with it
TaskInformational influences-
Environmental influences-
Personal influences
Organizational influences
The importance of controlling environmental factors to maximise workplace performance.
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The influence of the psychological human factors of noise and temperature on the design of an open-plan office.
Consideration should be made for sound-absorbing acoustic partitions to keep noise of conversations isolated. Noisy equipment
such as photocopiers and printers might be also isolated in a separate area.
Low silent phone tones, ventilation flow, static and dynamic tasks also need to be considered to make the environment effective
and productive. Space is often allocated based on standardized tasks or office status.
Office environments are more beneficial if they are well lit with natural lighting and have some natural influences such as the
use of timber and views and use of indoor and outdoor plants
Perception
Assessing the impact of perception in relation to the accuracy and reliability of psychological factor data. Perception (from the
Latinperceptio, percipio) is the organization, identification, and interpretation of sensory information in order to represent and
understand the environment. The issue is that we all perceive things differently. Look at the
slideshare presentation below and discuss some of the issues
http://www.slideshare.net/CommunicationKC/measuring-perception-for-beginners-comm-kc
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1.1c Physiological Factors
Nature of design:
Designers study physical characteristics to optimize the user’s safety, health, comfort and performance. (1.5, 1.18, 1.20, 2.9)
Concepts and principles:
Physiological factor data
Comfort and fatigue
Biomechanics
Guidance:
Types of physiological factor data available to designers and how they are collected
How data related to comfort and fatigue informs design decisions
The importance of biomechanics to the design of different products considering muscle strength, age, user interface and torque
Physiological factor data
Types of physiological factor data available to designers and how they are collected
When designing industrial or consumer products, physiological factors must be taken into account
ie. How users interact with products and specifically their physical comfort.
Physiological factors that affect ergonomics:
Physical limitations
How the body moves
Hand/eye coordination
Strength
Size
Stamina - muscle strength/endurance in different body positions
Visual sensitivity ie. To light
Tolerance to extremes of temperature
Frequency and range of human hearing
Body Tolerances: How much the body can withstand when using or working with a product
Look at the interesting link below. Curious Rituals is a fascinating design study that
illustrates all of the strange ways we bend our bodies (and our psyches) for the
technology we hold so dear.
http://curiousrituals.wordpress.com/
You can download the free book that was created here
Types of physiological factor data available to designers and how they are collected
Below are examples of the instruments used to collect human factors data and how
they are used
Torso Caliper
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This caliper works similar to those used in our workshops- vernier caliper. These torso calipers make a direct reading of the
distance between the subject's back and the front of the subject's abdomen.
Anthropometer
The Anthropometer is a counter recording instrument which can be effortlessly
operated from the tips of its branches. Its user can, therefore, by means of his free
fingertips actually feel his way to his desired measuring points in order to obtain a
degree of accuracy.
Cloth Tape
Flexible cloth or ribbon tape measure which can be moulded round the
body.
Sitting Height Table
The Sitting Height Table has a standard type of ball-bearing
mounted, counter-balanced head block, giving accurate and
direct readings from 320 mm to 1090 mm.
In Addition it has a secondary carriage, fitted with an antireverse carriage lock, in order to compensate for upper leg
variations: and an adjustable foot-rest in order to compensate
for lower leg variations.
Stadiometer
The Stadiometer is a counter recording instrument, with an
effortless counter balanced movement. It will give an accurate
and direct reading, to the nearest millimeter over a range of
600 mm to 2100 mm.
How data related to comfort and fatigue informs design
decisions
Comfort
What is Comfort?
Physical comfort, i.e. how pleasing it feels to use a product, is
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one of the first things a human will notice If something is not pleasant to the touch, people will not want to touch it or
ultimately use or operate it/.
Comfort is of primary concern to designers. It determines how effective a design is and how well a human can interact with a
product.
How comfortable to use something is to use is extremely important. If it’s comfortable the user will want to continue using it, if
it’s not they won’t. The utility of an item is a good way to measure the quality of a design.
The job of any designer is to find innovative ways to increase the utility of a product. Making an item intuitive and comfortable
to use will ensure its success in the marketplace. Physical comfort while using an item increases its utility.
The mental aspect of comfort in the human-machine interface is found in feedback. You have preconceived notions of certain
things. A quality product should feel like it is made out of quality materials. If it is lightweight and flimsy you will not feel that
comfortable using it.
The look, feel, use and durability of a product help you make a mental determination about a product or service. Basically it lets
you evaluate the quality of the item and compare that to the cost. Better ergonomics mean better quality which means you will
be more comfortable with the value of the item.
Below is a great article explaining how Fastco ensure comfort on the new airbus
http://www.fastcodesign.com/3028839/terminal-velocity/350-people-8-hours-airbus-tests-how-not-to-make-passengers-gonuts?partner=newsletter
http://www8.hp.com/us/en/hp-information/ergo/index.html#work-better
http://www.apple.com/about/ergonomics/index.html
Task- Look at the information on the sites above. Explain the main issues and solutions to how comfort can be improved in the
office workspace
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How data related to comfort and fatigue informs design decisions
Fatigue
Fatigue is the temporary diminishment of performance. Fatigue can be physical and/or
mental.
http://www.youtube.com/watch?v=nsxaD3Euz2Q
Watch the video above.
What are the main factors that create fatigue?
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In the workplace what are the main factors that create fatigue in the workplace?
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What are the short term and long term effects in the workplace and what are the major hazards?
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Read the information below
http://www.hse.gov.uk/humanfactors/topics/specific2.pdf
How can fatigue issues be managed in the workplace?
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Human Error
Human error has been seen as a key factor associated with almost every major accident,
with catastrophic consequences to people, property and the environment. Accidents
with major human contributions are not limited to any particular parts of the world, or
any particular industry, and include the Aberfan mining disaster (1966), the Bhopal
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chemical release (1984), the Chernobyl meltdown and radioactivity release (1986), the Piper Alpha platform explosion (1988)
and the Kegworth air disaster (1989).
http://news.bbc.co.uk/2/hi/science/nature/461738.stm
Human Reliability Assessment (HRA) can be defined as a method to assess the impact of potential human errors on the proper
functioning of a system composed of equipment and people. HRA emerged in the 1950s as an input to Probabilistic Safety (or
Risk) Assessments (PSA or PRA). HRA provided a rigorous and systematic identification and probabilistic quantification of
undesired system consequences resulting from human unreliability that could result from the operation of a system. HRA
developed into a hybrid discipline, involving reliability engineers, ergonomists and psychologists.
Here is some useful information on what human error is and how it is caused. Read the information
http://ergonomics.about.com/od/ergonomicbasics/a/What-Is-Human-Error.htm
What are the main causes of human error?
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Designing ergonomically enhanced work environments and products, has advantages for the employer and employee.
Healthy Workforce – Instead of workers adjusting to standard tools and equipment, ergonomics promotes product designing
based on human body structure and requirements. Therefore, these products drastically reduce the strain workers experience
due to repetitive use of machines, computers, scanners, industrial apparatus and related instruments. Less strain equates to
reduced instance of occupational illnesses and therefore healthier employees.
Enhanced Productivity – A healthy workforce translates to enhanced productivity. Easy to use equipment keeps the work
momentum going on for longer durations. Workers experience less fatigue and are happy to use tools designed especially for
them.
Reduced Number of Sick Days Reported – People with reduced instance of work associated ailments implies they take fewer
days off due to sickness and work more number of days in a year. This means lesser number of workdays is lost.
Savings – By using ergonomic workstations, employers save huge amounts of money otherwise spent in compensation claims,
treatments and litigation.
https://nonprofitrisk.org/tools/workplace-safety/nonprofit/c5/layout.htm Use this website to add detail to the points below
Workplace design and workspace layout
Workplace design and workspace layout: the way in which any work space is arranged can impact a
worker’s health and performance. An optimal layout ensures a person stays in the best posture and uses
the least effort to perform the work. Principles of optimizing workplace layout include:
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1) Convenience— frequently used equipment is most conveniently located;
2) Location— equipment can be easily accessed without postural deviations (bending, leaning, or twisting); and
3) Frequency—frequently performed tasks are located together.
Physical environment conditions at work: ergonomists address issues of lighting, thermal comfort, indoor air quality (IAQ),
noise, disturbances, vibration, and electromagnetic fields.
Job design, selection, and training: these are ways of organizing work activities to maximize work output and quality without
adversely affecting workers.
Organizational design and management: includes peoples’ motivations and how to best organize them into teams.
Biomechanics
The importance of biomechanics to the design of different products
considering muscle strength, age, user interface and torque
Biomechanics - The science of measuring the amount of force put
on the muscles and joints of people when working in different
positions.
In other words, determining which positions make use of an
individual’s muscular strength. A muscle’s ability to perform is affected by the way it is used or another way to say it is the
activity the muscle is performing. The activity can be either Static or Dynamic.
STATIC - Holding one object or body part in one position for an extended period.
eg. Standing or sitting in a parking booth or at a microscope.
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Think about how tiring you get when you sit or stand in one position for a long period of time. In an office it might be at the
computer all day without a break, think about how tiring that feeling is. Or it could be standing in one position all day
performing the same tasks or driving for several hours. Muscles fatigue faster when they are held in one position.
DYNAMIC - An activity created by the rhythmic contraction and relaxation of the muscles. eg. Walking
Dynamic work positions, that is positions that change, allow muscles to rest during the relaxation phase.
The importance of biomechanics to the design of different products considering muscle strength, age, user interface and torque
http://www.inclusivedesigntoolkit.com/betterdesign2/UCdex/dex.html
http://www.designcouncil.info/inclusivedesignresource/Mattwhite/casestudy.pdf
User Interface Hardware or software that is seen, heard or otherwise sensed, and the commands and mechanisms the user must use to control
the system / object
eg. Car
User interface consists of the steering wheel, the accelerator pedal, the brake pedal, the various instruments that the user
requires, etc.
eg. Operating system or application software
The user interacts using menus, icons, keystrokes, mouse clicks, and similar capabilities
Recently, as systems have become increasingly complex and more difficult to control, much thought has been given to the
design of interfaces that enable a user to operate the system naturally. This increases its usability by allowing the user to form a
mental model of the system. The term user friendliness (or user centered or user centric design) has been coined as a measure
of how well the user interface fulfills this goal. (Based on Wikipedia).
User Interface design is closely related to Engineering Psychology and Human Factors. We generally use the term User Interface
Design to refer to the design of displays and controls in an effort to make them more usable, user friendly, or user centered.
http://www.coventry.ac.uk/research/research-directory/art-design/centre-for-product-and-automotive-design/designergonomics/educational-ergonomics/
In the above link three case studies are explored that were conducted at the University of Coventry in the U.K.
Watch the video below
http://www.youtube.com/watch?v=79yH4fCXv88
Task- Explain some of the important issues discussed in the video.
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Factors affecting Muscle strength:
● Gender
● Age - Greatest around 20’s
- 5% less in 40’s
- 20% less in 60’s
● Pain, Physical training schedule, Immobilization or bed bound
Use the examples over the page to explain the importance of
biomechanical factors to making the design a success. Explain in relation to
two of the personas here. Obviously don’t choose Jack as he is too young
to operate the equipment.
(Consider- muscle strength, age, user interface and torque)
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Below are some examples of common kitchen appliances. What do you think are the major difficulties that users with limited
hand movements may have with them? Use the sites below to find alternative design solutions
http://www.seniors-superstores.com/KITCHEN/b/8036193011?ie=UTF8&title=KITCHEN
http://www.oxo.com/s-24-cooking-baking.aspx
Appliance
Difficulties
Solution (paste below)
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