Human Factors

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Human Factors

• Rolla
• Session 5
• September 20, 2001

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LIFTING TASKS

• AMOUNT LIFTED
• FREQUENCY OF LIFT
• DISTANCE LIFTED
• HORIZONTAL LOCATION WHERE LIFT BEGINS

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LIFTING TASKS

• VERTICAL LOCATION WHERE LIFT BEGINS
• LOWERING AN OBJECT IS THE SAME AS LIFTING IF NOT
  RELEASED AND DROPPED TO THE FLOOR

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METHODS OF ANALIZING

• FIGURE 8-27 PAGE 260 DOESNT TELL US ANYTHING
• FIGURE 7-22 FROM ANOTHER TEXT
  (See Next Slide)
• NIOSH FORMULA APPENDIX D PAGE 769

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(No Transcript)
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NOTE THE FACTORS FOR NIOSH FORMULA

• HORIZONTAL LOCATION 6/H
• VERTICAL LOCATION 1-(.01 X ?V - 30?)
• VERTICAL DISTANCE TRAVELED 0.7 3/D
• FREQUENCY OF LIFT 1-F/FMAX
• SEE PAGE 770

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WHY IS HORIZONTAL LOCATION AT POINT OF LIFT
IMPORTANT??

• LOOK AT FIGURE 8-24 ON PAGE 256

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• OBJECT SIZE
• INCREASE HEIGHT AND THEN WIDTH
• OBJECT SHAPE BAGS VS BOXESLOAD
  DISTRIBUTION HANDLES?

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ONE WAY TO CATEGORIZE HEIGHT OF LIFT

• FLOOR TO KNUCKLE
• KNUCKLE TO SHOULDER
• ABOVE SHOULDER MOST DEMANDING AVOID

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PUSHING TASKS AT SHOULDER HEIGHT PAGE 263
FIGURE 8-30
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MOTOR SKILLS CHAPT 9 WHY???? MOTOR SKILLS
REQUIRED TO ACTUATE CONTROLS
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RANGE OF MOVEMENT SEE PAGE 275 FIGURE 9-1A
DESCRIPTIVE STUDYWHY 5 50 95
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MOVEMENT TIME SEE FIGURE 9-9 PAGE
290 APPLICATIONS?????
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ACCURACY OF MOVEMENTS STUDY ON PAGE 294 FIGURE
9-11
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THE RELATIONSHIP BETWEEN CONTROLS AND
DISPLAYS WE HAVE A CONTROL THAT MOVES A DISPLAY
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SPATIAL COMPATIBILITY PHYSICAL SIMILIARITIES
BETWEEN DISPLAYS AND CONTROLS ARRANGEMENT
OF DISPLAYS AND THEIR CONTROLS SEE STUDY PAGE
305
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MOVEMENT COMPATIBILITY STEERING WHEEL TO RIGHT
CAR GOES TO THE RIGHT
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ROTARY CONTROLS AND ROTARY DISPLAYS IN SAME PLANE

• STRONG RELATIONSHIPS
• SCALE SHOULD ROTATE IN THE SAME DIRECTION AS THE
  CONTROL KNOB
• SCALE NUMBERS SHOULD INCREASE FROM LEFT TO RIGHT
• CONTROL SHOULD TURN CLOCKWISE TO INCREASE
  SETTINGS
•  SEE STUDY ON PAGE 308

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ROTARY CONTROLS AND LINEAR DISPLAYS IN THE SAME
PLANE

• THREE PRINCIPLES1)    WARWICK2)   
  SCALE-SIDE3)    CLOCKWISE FOR INCREASE

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MOVEMENT OF DISPLAYS AND CONTROLS IN DIFFERENT
PLANES SEE FIGURES 10-7, 10.8, AND 10.9
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READ CHAPTER 11 AND 12 FOR NEXT WEEK
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DESIGN OF CONTROLS AND ENTRY SYSTEMS

• WHAT TYPE -SIZE OR DIMENSIONS
• LOCATION
• MULTIPLE CONTROLS
• CONTROL/RESPONSE RATIO
• IDENTIFICATION
• RESISTANCE
• WHY ARE CONTROLS IMPORTANT??

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BE SURE AND HAVE YOUR BOOK FOR NEXT WEEK. WE
NEED TO CROSS REFERENCE SOME SECTIONS