DESIGN FOR HUMAN FACTORS

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DESIGN FOR HUMAN FACTORS
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http//www.3dcontentcentral.com/secure/download-mo
del.aspx?catalogid171id111880
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HUMAN - FACTORS ENGINEERING
Human factors data may exist as 1. Expert
judgments 2. Experience and common sense 3.
Design standards 4. Established design
principles 5. Graphic representations 6.
Quantitative data tables 7. Mathematical
functions and expressions
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DESIGNING USER-FRIENDLY PRODUCTS

• Some important questions to ask
• 1. Can each control device be easily
  identified?
• 2. Is the visual display arrangement optimized?
• 3. What sensory channel would be most suitable
  for a message to be communicated through the
  displays?
• 4. Does the design effectively use human
  decision making and adaptive capabilities?
• Are the controls effectively designed with
  respect to shape, size, accessibility?
• Does the design effectively address the
  possibility of grouping the tasks to be performed
  into jobs?
• Are control devices compatible with their
  corresponding displays, with respect to human
  factors?
• For satisfactory levels of human performance,
  were such environmental factors as noise,
  temperature, and illumination taken into
  consideration?

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HUMAN INTERACTIONS WITH A PRODUCT

• Considering human factors during the design
  process means being aware of the user of the
  product as the occupant of a workspace, a source
  of power, a sensor, and a controller .
• Readily available statistical data should be used
  in designing size and power relationships between
  a human user and the product being designed.
• Product safety implies concern for injury to
  humans and for damage to the device itself, other
  equipment, or the environment.

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HUMAN INTERACTIONS WITH A PRODUCT

• Safety can be
• designed into a product
• added on
• the hazard warned against
• The first of these is best the last is often
  unacceptable.

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HUMAN INTERACTIONS WITH A PRODUCT
Correct
Incorrect
The preferred position of the elbow when holding
a device when force or weight are involved.
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TYPES OF VISUAL DISPLAYS
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APPROPRIATE USES OF COMMON VISUAL DISPLAYS
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USER FRIENDLY DESIGN
Original cloths dryer panel
Redesigned cloths dryer control panel
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USER FRIENDLY DESIGN
Before Tool Redesign
After Tool Redesign
The handle on the right is much more
user-friendly for a lever or tool that must be
pushed with considerable force.
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DESIGN FOR HUMAN FACTORS
"Photograph courtesy of www.baddesigns.com"
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DESIGN FOR HUMAN FACTORS
bad
good
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DESIGN FOR HUMAN FACTORS
bad
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DESIGN FOR HUMAN FACTORS
"Photograph courtesy of www.baddesigns.com"
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DESIGN FOR HUMAN FACTORS
"Photograph courtesy of www.baddesigns.com"
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"Photograph courtesy of www.baddesigns.com"
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DESIGN FOR HUMAN FACTORS
"Photograph courtesy of www.baddesigns.com"
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DESIGN FOR HUMAN FACTORS
"Photograph courtesy of www.baddesigns.com"
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DESIGN FOR HUMAN FACTORS
"Photograph courtesy of www.baddesigns.com"
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DESIGN FOR HUMAN FACTORS
"Photograph courtesy of www.baddesigns.com"
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DESIGN FOR HUMAN FACTORS
"Photograph courtesy of www.baddesigns.com"
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DESIGN FOR HUMAN FACTORS
"Photograph courtesy of www.baddesigns.com"
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DESIGN FOR HUMAN FACTORS
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DESIGN FOR HUMAN FACTORS
Which way to turn for warmer water?
Bad
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DESIGN FOR HUMAN FACTORS
"Photograph courtesy of www.baddesigns.com"
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DESIGN FOR HUMAN FACTORS
"Photograph courtesy of www.baddesigns.com"
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DESIGN FOR HUMAN FACTORS
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DESIGN FOR HUMAN FACTORS
Bad
Good
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DESIGN FOR HUMAN FACTORS
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Good
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DESIGN FOR HUMAN FACTORS
Bad
Good
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DESIGN FOR HUMAN FACTORS
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Bad
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DESIGN FOR HUMAN FACTORS
Bad
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DESIGN FOR HUMAN FACTORS
Bad
Good?
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DESIGN FOR HUMAN FACTORS
Bad
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DESIGN FOR HUMAN FACTORS
Q. What are you, stupid? These things aren't bad
designs! You're just too stupid to figure out how
to use them! You have no common sense. You're too
lazy to read instructions. A. Things designed
for common use should not require that people
have an above average intelligence and should not
require them to expend a lot of mental energy or
time learning, problem solving or reading
instructions. If designers want their products to
be widely used, they are well-advised to design
them so that they are easy to use.
www.baddesigns.com
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DESIGN FOR HUMAN FACTORS
Q. How can I make sure the product I am working
on is easy to use? A. First, determine who is
going to use your product - for example, the
group's age and experience level. Determine what
features are going to be used most often and what
basic tasks people will perform with the product.
Build a prototype of your product that allows
people to perform the tasks - at least to some
degree. Higher fidelity prototypes are better,
but good feedback can be obtained from low
fidelity prototypes. Next, find some people who
are like the ones who will be using your product
and have them perform some typical tasks with the
prototype. Observe the people to see what
confused them, where they make mistakes or are
inefficient. Then modify the prototype to reduce
or eliminate these problems. Repeat this process
until you have eliminated the problems.
www.baddesigns.com
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HUMAN - FACTORS ENGINEERING

• Human-factors engineering deals with applying the
  knowledge gained from human physiology and
  psychology (concerning the characteristics and
  capabilities of the human body and mind) to
  product design and use.
• These include such factors as height, weight,
  vision, hearing, posture, strength, age,
  intelligence, educational level, dexterity, and
  reaction time.
• A variety of qualitative and numeric data are
  available to describe these characteristics.

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GENERAL OBSERVATIONS OF HUMAN BEHAVIOR

• People often
• are reluctant to admit errors
• perform tasks while thinking about other things
• misread or overlook instructions and labels
• respond irrationally in emergency situations
• become complacent after successfully handling
  dangerous items over a longer period of time

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GENERAL OBSERVATIONS OF HUMAN BEHAVIOR

• People often
• fail to recheck outlined procedures for errors
• poor estimators of speed, clearance, or distance
  (they frequently overestimate short distances and
  underestimate larger distances )
• too impatient to take the time needed to observe
  precautions
• reluctant to admit that they cannot see objects
  well enough, due either to poor eyesight or to
  inadequate illumination and use their hands for
  examining or testing.

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CATEGORIES OF HUMAN ERROR
1. Operation error - attributed to operating
personnel. Causes improper procedures, poor
surrounding environment, task complexity,
overload conditions, operator carelessness,
inadequate personnel training or selection, and
incorrect operating procedures.
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CATEGORIES OF HUMAN ERROR
2. Maintenance error - occur in the field and
are attributable to maintenance
personnel. Examples the use of the wrong grease
to lubricate the equipment, and the incorrect
calibration of the equipment.
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CATEGORIES OF HUMAN ERROR
3. Design error - reflect inadequate
designs. Causes inadequate analysis of the
system requirements, designer's bias toward a
specific design, insufficient time spent on the
design.
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CATEGORIES OF HUMAN ERROR
4. Inspection error Purpose of inspection is to
uncover all items with defects, however,
inspection effectiveness often averages around
85.
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CATEGORIES OF HUMAN ERROR (CONTD)
5. Fabrication error - result from poor
workmanship during product assembly. Causes poor
blueprints, inadequate illumination, poor
workstation layout, excessive noise etc.
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CATEGORIES OF HUMAN ERROR (CONTD)
6. Installation error - attributed to incorrect
or incomplete installation of the
product. Primary cause failure to follow the
instructions or blueprints.
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CATEGORIES OF HUMAN ERROR (CONTD)
7. Handling error - due to the inappropriate or
improper storage or transport of a product, and
can result in damage to the product. Example
improper packaging for shipment.
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CATEGORIES OF HUMAN ERROR (CONTD)
8. Contributory error This classification
covers those errors that are difficult to
identify as either human or hardware.
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CATEGORIES OF HUMAN ERROR (CONTD)
Hartford Civic Centre Arena roof
collapse. Failure occurred due to modeling error
model was not validated. http//www.eng.uab.edu/ce
e/faculty/ndelatte/case_studies_project/Hartford2
0Civic20Center/hartford.htmTop
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CATEGORIES OF HUMAN ERROR (CONTD)
Sinking of Sleipner A platform Failure occurred
due to due to discretization error model was not
verified. http//www.ima.umn.edu/arnold/disasters
/sleipner.html
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CATEGORIES OF HUMAN ERROR (CONTD)
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CATEGORIES OF HUMAN ERROR (CONTD)
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PRODUCT SAFETY AND LIABILITY

• The following must be considered when designing
  products
• Safety standards and criteria for safe design.
• How a product will function and the impact of
  user/operator error.
• Analysis of safety problems, failures, and
  malfunctions during prototype testing.
• Is the product toxic? Can it be easily
  maintained? Does it have protective guards?
  Warning labels? Hot surface? Rotating blades and
  sharp edges? etc.
• Sudden acceleration/deceleration, pressure
  hazards, radiation, vibration,electrical and fire
  hazards, etc.

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PRODUCT SAFETY AND LIABILITY

• The following must be considered when designing
  products
• Adequate factor of safety and system redundancy.
• Cost of failure repair, cost of malfunction, cost
  of injury, cost of component and subassembly
  replacement.
• Impact of product usage on the environment.
• Instructions for use, troubleshooting, minor
  repair, and routine maintenance.
• Design deficiencies such as inadequate
  identification, lighting, and accessibility.

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SAFETY GUIDELINES

• Eliminate hazards by modifying design,
  maintenance procedures, or material used.
• Control hazards at their source through guarding,
  enclosing, or capturing.
• Provide necessary warnings/instructions in
  documentation and display them in effective
  places.

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SAFETY GUIDELINES

• Educate people to be aware of hazards and to
  follow appropriate steps to avoid them.
• Expect certain abuse and misuse, and take
  necessary measures to reduce their consequences.
• Provide suitable protective equipment to people,
  and develop steps for ensuring that it is
  effectively used.

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LABELS AND WARNINGS
1. Caution - used under conditions where hazards
or unsafe practices may lead to minor personal
injury, and/or minor damage to the product or to
property. 2. Danger - used where immediate
hazards (if they occur) would lead to severe
personal injury or death. 3. Warning - used
where hazards or unsafe acts (if they occur)
could lead to severe personal injury or death.
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LABELS AND WARNINGS