Anthropometry and Range of Motion

AnthropometryDefinitionThe study of the dimensions and certain other physical

characteristics of the human body

ItisderivedfromtheGreekwords‘anthropos’(man)and‘metron’(measure).

§ Critical element in workplace design- Accommodate users

§ Large volumes of data available- Different sexes, ages, and geographical regions

AnthropometryIntroduction

Freivalds A., (2009) . Niebel’s Methods, Standards, and Work Design. McGraw-Hill

TYPESOFANTHROPOMETRICDATA

1. StructuralAnthropometricData

2. FunctionalAnthropometricData

1.STRUCTURALANTHROPOMETRICDATA

§ Structuralanthropometricdataaremeasurementsofthebodilydimensionsofsubjectsinfixed(static)positions.

EXAMPLES§ Tospecifyfurnituredimensions.§ Todeterminerangesofclothingsizes.

2.FUNCTIONALANTHROPOMETRICDATA

§ Functionalanthropometricdataaretakenunderconditionsinwhichthebodyisengagedinsomephysicalactivities.

EXAMPLES

§ Designofcranecabs§ Designofvehicleinteriors

USESOFANTHROPOMETRICDATA

§ Tofitthetasktotheperson.

§ Toavoidphysicalmismatchesbetweendimensionsof

equipmentandproductsandthecorrespondinguser.

§ Todesignforvariabilityinpeopleandnotfortheaverage.

AnthropometryIntroduction

Variation in body dimensions§ Enormous variation in body size among individuals§ Challenges

- Designing workstations and equipment§ Who do we design for?

- Average person- Extreme body sizes, i.e. largest or smallest

§ Careful considerations required for design cut off points§ Depends on the design purpose

Kroemer, K.H.E.., Grandjean, E. (1997) Fitting the Task to the Human. Taylor & Francis

AnthropometryIntroduction

Kroemer, K.H.E.., Grandjean, E. (1997) Fitting the Task to the Human. Taylor & Francis

Factors affecting body dimensions§ Human Variation

- Age- Gender- Ethic Origin- Long-term population Shifts

§ Clothing and Personal Equipment

AnthropometryIntroduction

§ Body dimensions is based on no clothes. Clothing will add to physical dimensions

§ Footwear and gloves can affect anthropometric dimensions- Allowances should be made to compensate

Pheasant, S., Haslegrave, C., (2006). Bodyspace: Anthropometry, Ergonomics, and the Design of Work. Taylor and Francis Group.

1.BODYDIMENSIONS

Minimum dimensions

§ Adoorhandlemustnotbelowerthanthehigheststandingknuckleheightinapopulationsothatalluserscanopenthedoorwithoutstooping.

MINIMUMDIMENSIONSCONT…..

§ Thewidthofachairmustbenonarrowerthanthehipbreadthofalargewoman.

MINIMUMDIMENSIONSCONT…..

§ Theheightofadoorwaymustbenolowerthanthestatureofatallman(plusanallowanceforclothingandshoes).

MAXIMUMDIMENSIONS

§ Adoorlockmustbenohigherthanthemaximumverticalreachofasmallperson.

MAXIMUMDIMENSIONSCONT…

§ Seatheightsanddepthsmustnotexceedthemaximumheightandbuttock–kneelengthsofsmallusers.

AnthropometryStatistical Basis for Anthropometry

Statistical procedure for anthropometric data§ Yield a wealth of information§ Assist in calculating percentiles and ranges of homogenous or

composite groups§ Anthropometric dimensions are normally distributed

- May be described by the mean and standard deviation- Accommodate users

§ Large volumes of data available- Different sexes, ages, and geographical regions

Freivalds A., (2009) . Niebel’s Methods, Standards, and Work Design. McGraw-Hill

AnthropometryStatistical Basis for Anthropometry

Freivalds A., (2009) . Niebel’s Methods, Standards, and Work Design. McGraw-Hill

§ Kth percentileDefinitionA value such that k percent of the data values are at or below this value

and 100 – k percent of the data values are at or above this value§ Percentiles provide a basis for estimating the proportion of a

population accommodated by a design§ Normal transformation

σµ−

=XZ

z = standard normal value corresponding to population cumulative densityX = value of measured dimensionµ = average, or mean of dimension for population SD = standard deviation of population

Anthropometry

§ Standard standing posture –subject stands erect looking straight ahead, arms to their side

§ Standard standing posture – erect on a horizontal flat surface and looking straight ahead

Kroemer, K.H.E.., Grandjean, E. (1997) Fitting the Task to the Human. Taylor & Francis

AnthropometrySelected Anthropometric Measurements for US Adults

Source: Bodyspace by Stephan Pheasant. Copyright @1998 by Taylor and Francis

5th 50th 95th St. Dev. 5th 50th 95th St. Dev.

1. Standing height 1640.0 1755.0 1870.0 71.0 1520.0 1625.0 1730.0 64.0

2. Sitting height 855.0 915.0 975.0 36.0 800.0 860.0 920.0 36.0

3. Knuckle height 700.0 765.0 830.0 41.0 670.0 730.0 790.0 37.0

4. Knee height 495.0 550.0 605.0 32.0 460.0 505.0 550.0 28.0

5. Popliteal height 395.0 445.0 495.0 29.0 360.0 405.0 450.0 28.0

6. Elbow-rest height 195.0 245.0 295.0 31.0 185.0 235.0 285.0 29.0

7. Thigh-clearance height 135.0 160.0 185.0 16.0 125.0 155.0 185.0 17.0

8. Buttock-knee length 550.0 600.0 650.0 31.0 525.0 575.0 625.0 31.0

9. Buttock-popliteal length 445.0 500.0 555.0 33.0 440.0 490.0 540.0 31.0

10. Hip breadth 310.0 360.0 410.0 30.0 310.0 375.0 440.0 25.0

11. Shoulder breadth (bideltoid) 427.0 470.0 515.0 28.0 360.0 400.0 440.0 25.0

12. Weight, kg. 55.0 78.0 102.0 14.0 41.0 65.0 89.0 15.0

Dimension

Female

Percentiles Percentiles

Male

(All dimensions in mm, except body weight given in kg)

Anthropometry1. Design for the individual

§ Best design BUT very expensive

§ Design dimensions to fit a specific individualExample: Design of a space suit

2. Design for an adjustable range

§ From 5th percentile (small female) to 95th percentile (large male)§ Adjust to fit a wider range of people§ Best BUT expensive

Example: Design of industrial chairs

3. Design for extremes

§ For the small female (5th percentile) OR the large male (95th percentile)Examples: Design of the door post - for the large male

Design of a shelf - for the small female

4. Design for the average

§ Not recommended§ Design for 50th percentile§ Only when used for a short duration

Example: Design counter at the supermarket or a public placeFreivalds A., (2009) . Niebel’s Methods, Standards, and Work Design. McGraw-Hill

Range of Variability of Voluntary and Passive Movements of Body Members (in degrees)

7.47474648.1667952Adduction

6.14040267274915Abduction

1392926715.2548032Extension

131061068010.69511073Flexion

Hand at wrist

15.211411493119911482Supination (turn out)

22.11051057625.89113959Pronation (turn in)

7.622221298.5138150126Flexion (bend)

Forearm at elbow

12.413713711611.7129154113Abduction(side)

11.968685110.1557140Extension

6.41851851717.2179191164Flexion (forward)

Arm at Shoulder

14.1971147216.1779551Rotation (right)

Head

SDMeanUpper Limit

Lower LimitSDMeanUpper

LimitLower LimitBody Member and Movement

PassiveVoluntary

Range of Variability of Voluntary and Passive Movements of Body Members (in degrees)

4.74444356.6374625Dorsal Flexion9.93636227.4284318Planter Flexion (bend up)

Foot at ankle1401401296.7127136118Flexion (bending)

Leg at knee joint6.74646396.6374824External Rotation

16.673734515.2618039Internal Rotation10.479796517709839Abduction (side)10.456564112.9487026Extension9.211211299179811963Flexion (forward)

Thigh at hip joint

SDMeanUpper Limit

Lower LimitSDMeanUpper

LimitLower Limit

Body Member and Movement

PassiveVoluntary

Goniometer

Ulnar Deviation (Transverse plane)

Wrist Flexion (Sagittal plane)

Range of Motion Movement

Range of Motion Factors Affecting Range of Motion

§ Age§ Gender§ Race§ Body build§ Exercise§ Occupation§ Fatigue§ Disease§ Motivation§ Right vs. left side of body§ Zero gravity§ Clothing and personal equipment

Range of Motion Factors Affecting Muscle Strength

Biological factors- Age- Gender- Race- Body build- Body position- Handedness- Fatigue- Exercise- Health- Diet- Drugs- Diurnal variations

Environmental factors- Altitude- Acceleration

Psychological factors- Motivation- Emotional state

Occupational factors- Occupation- Clothing and personal equipment- Workplace equipment

Guidelines for Conversion of Standard Measuring Postures to Functional Stances and Motions

To consider Do thisSlumped standing or sitting Deduct 5 – 10% from appropriate height measurementsRelaxed trunk Add 5 – 10 % to trunk circumferenceWearing shoes Add approximately 25 mm to standing and sitting

heights; more for high heelsWearing light clothing Add about 5% to appropriate dimensionsWearing heavy clothing Add 15% or more to appropriate dimensions (Note:

Mobility may be strongly reduced be heavy clothing)Extended reaches Add 10% or more for strong motions of the trunkUse of hand tools Center of handle is at about 40% of hand length,

measuredComfortable seat height Add or subtract up to 10% to or from standard seat

height

Kroemer, K.H.E.., (2008) Fitting the Task to the Human, 6th Ed. Taylor & Francis.

ADVANTAGESOFANTHROPOMETRICDATA

§ Increaseaccuracy§ ReduceFatigue§ Bettercomfort§ Reducechanceofinjuries§ Timemanagement

CONCLUSION

§ Anthropometryplaysamajorroleinincreasingproductivityoftheorganization.

§ Basedonthepopulationwehavetodesigntheworkspaceandequipment's.

§ Accordingtothelevelofcomfortabilitythequalityoftheproductwillgetraise.

REFERENCE

§ BridgerR.S(2008).IntroductionToErgonomics,3rdEdition.

§ http://en.wikipedia.org/wiki/Anthropometry§ http://personal.cityu.edu.hk/~meachan/Online%20Anth

ropometry/Chapter1/Ch1-7.htm