Applied Anthropometry and the Workplace.ppt

1、Applied Anthropometry and the Workplace,AnthropometryA. Description of the physical variation in humans by measurement; a basic technique of physical anthropology.,B. The measurement of the dimensions and certain other physical characteristics of the body.,Measuring Types,A. Static (structural) - ta

2、ken while the body is in a static position1. Skeletal dimensions - joint-to-joint measurement2. Maximum body width,3. Data available on most characteristics of the bodyNASA Anthropometric Source Book. (vol 2, 1978),Measuring Types,B. Dynamic (functional)1. Measurements taken while the body is engage

3、d in some kind of activitya. Driving a car b. Working at a desk / VDT terminal,Applications,Principles1. Design for extremes of individuals (or the population)a. Maximum: automobile interiors, escape hatches, doorwayb. Minimum: applied force, reach distances,c. Most designs cover 5th through 95th pe

4、rcentile,Principles,2. Design with an adjustable rangea. Design should “fit“ 5th through 95th percentile of relevant populationb. Involves a trade-off with cost/complexity,3. Design for the average - vs. design for the extreme (seat height, counter tops, letter height),4. Variability of population -

5、Anthropomorphic measurements are a functionof age, gender, nationality, user type and several other factors,Principles,Applications of Design Principles,A. BittnerTaking 13 dimensions between 5th and 95th percentile excluded 52% of the populationB. Body dimensions are not perfectly correlated,Short

6、legs with a long torso in automobile design,Applications of Design Principles,C. Physical modeling1. Computer programs to model human movement2. Dummies are used to represent specific percentiles - crash tests for autos,General Approach for Design Evaluation,A. Determine the body dimensions which wi

7、ll be important in the use of the systemB. Define the relevant (user) population,C. Which design principle will be used,D. What percentage of the population it is to be designed forE. Determine the relevant value from the anthropomorphic tablesF. Add appropriate allowances for special situations,Gen

8、eral Approach for Design Evaluation,1. Bulky clothing worn in cold weather 2. Protective clothing worn by hazardous duty personnel,Work Spaces (Envelopes),A. Work Space EnvelopeDefined as the 3-dimensional space around an individual in which it is reasonably optimal for persons to perform some type

9、of manual activityB. Seated personnel1. Most important factor in this position is arm reacha. direction ofreachb. task to be performed (grasp, fingertip operation)c. type of reaching motion (restricted/unrestricted),2. Design for the minimum (5th percentile) - Makes it useful for 95% of the populati

10、on3. Consider apparel wornC. Standing Personnel,Work Spaces (Envelopes),1. vs. seateda. Larger workspace is defined (due to ability to bend/reach)b. Workspace is dynamic (moves as the person moves),Work Spaces (Envelopes),D. Clearance Requirements workers need to fit into awkward or restrictive spac

11、es sometimes. i.e. maintenance or emergency hatches.,Work Surfaces,A. Horizontal Surfaces (tables, desks, counters)1. Normal area - area covered by sweep of the forearm while the upper arm remains in a natural position,2. Maximum area - area which can be reached by extending the arm from the shoulde

12、r,B. Slanted Surfacesvs. horizontala. Eastman and Kodat (use of slanted surfaces, 12-24 degrees, gives better posture, less fatigue/discomfortb. Drafting tables, computer keyboardsC. Height of Work Surfaces,Work Surfaces,Work Surfaces,Guidelinesa. Make it adjustable where possible (legs/feet, slant)

13、b. Forearm should be level of slightly down with shoulders relaxed (not hunched)c. Allow for a “straight“ spine (posture) to reduce strain and fatigue in the back muscles/spine,d. Adjustable for type of activity to be performed,Work Surfaces,2. For Standing Personnela. Precision work (work level eve

14、n with or slightly above elbow height)b. Light / Heavy work (work level should be below elbow height),Seating,Principles of Seat Design1. Back support should be used a. Lower support most critical to reduce fatigue and eliminate back painb. Lordotic (concave) preferred over Kyphotic (convex),2. Seat

15、 height and slope,Seating,a. Generally, seat height should be low enough so as to reduce pressure on the underside of the thigh (reduces blood flow to the legs)b. Common to design seats for minimum (5th percent),3. Seat depth and width a. For public seating, depth should be designed for a minimum wh

16、ile the width should be designed for the maximum,Seating,b. Spacing between seats should be at least 20 inches,Guidelines for Seat Design,A. Seat back should provide support for lumbar (lower) areaB. Seat back should have moderate inclination (10-30 degrees)C. Seat pan should slope back slightly,D.

17、Angle between seat pan and back is 95-120 degrees,E. Seat height and backrest should be adjustableF. Seat height designed for small people, width for large peopleG. Use moderately contoured seat pan for weight distribution,Guidelines for Seat Design,Seat Height and Slope: - fixed height: 18 - 19” -

18、adjustable height: 16 - 20.5” - slope: 0 - 10o backward tiltSeat Depth and Width: - depth: 15 - 17” - width: 18.2”,Guidelines for Seat Design: ANSI Standard,Guidelines for Seat Design: ANSI Standard,Contour and Cushioning: - contour: tradeoffs between even weight distribution vs. restricting movemen

19、t and postural fixity. - cushion: 1.5 - 2” thick.Seat Back: - angle: minimum 90 - 105o with respect to the seat pan. Up to 120o prefered. - width: minimum 12” in the lumbar region. - height: minimum 19.5”. - lumbar support: 6 - 9” high, 12” wide, positioned 6 - 10” above seat reference point, and protrude 2” from back rest.,