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Anthropometrics II
Rad Zdero, Ph.D.University of Guelph
• Anthropometric Data Tables
• Example• Using and Generating
Anthropometric Data
• Ergonomic Design Principles
• Ergonomic Design Approach
Outline
AnthropometricData Tables
Figure 1. Static BodyFeatures. Structural Dimensions for U.S.Adults (1989).
(see also Figure 2 andTables 1 to 4 for Values)
[source: Kroemer, 1989]
Figure 2. Percentile of Population Group
Normal or GaussianData Distribution
No. ofSubjects
5th percentile = 5 % of subjectshave “dimension”below this value
50 %95 %
Dimension(e.g. height,weight, etc.)
Table 1 - U.S. Adult Civilians (1989)
Segment Gender 5 th Percentile
50 th Percentile
95 th Percentile
1. Stature M
F
161.8 cm
149.5
173.6 cm
160.5
184.4 cm
171.3
2. Eye Height M
F
151.1
138.3
162.4
148.9
172.7
159.3
3. Shoulder Height
M
F
132.3
121.1
142.8
131.1
152.4
141.9
4. Elbow Height
M
F
100.0
93.6
109.9
101.2
119.0
108.8
5. Knuckle Height
M
F
69.8
64.3
75.4
70.2
80.4
75.9
See “Static Body Features” Figure 1 for exact dimension
Table 2 - U.S. Adult Civilians (1989)
Segment Gender 5 th Percentile
50 th Percentile
95 th Percentile
6. Height (sit) M
F
84.2 cm
78.6
90.6 cm
85.0
96.7 cm
90.7
7. Eye Height (sit)
M
F
72.6
67.5
78.6
73.3
84.4
78.5
8. Elbow Height (sit)
M
F
19.0
18.1
24.3
23.3
29.4
28.1
9. Thigh Clearance (sit)
M
F
11.4
10.6
14.4
13.7
17.7
17.5
10. Knee Height (sit)
M
F
49.3
45.2
54.3
49.8
59.3
54.5
See “Static Body Features” Figure 1 for exact dimension
Table 3 - U.S. Adult Civilians (1989)
Segment Gender 5 th Percentile
50 th Percentile
95 th Percentile
11. Buttock-to-Knee (sit)
M
F
54.0 cm
51.8
59.4 cm
56.9
64.2 cm
62.512. Thigh-to-Heel Height (sit)
M
F
39.2
35.5
44.2
39.8
48.8
44.3
13. Chest Depth (stand)
M
F
21.4
21.4
24.2
24.2
27.6
29.7
14. Elbow-to-Elbow (sit)
M
F
35.0
31.5
41.7
38.4
50.6
49.1
15. Hip Width (sit)
M
F
30.8
31.2
35.4
36.4
40.6
43.7
See “Static Body Features” Figure 1 for measured dimension
Table 4 - U.S. Adult Civilians (1989)
Segment Gender 5 th Percentile
50 th Percentile
95 th Percentile
Weight (kg) M
F
56.2 kg
46.2
74.0 kg
61.1
97.1 kg
89.9
See “Static Body Features” Figure 1 for measured dimension
Note for Tables 1-4: Due to anatomical reasons, Male data islarger than Female data at all %iles, with the exception of#13 (Chest Depth) and #15 (Hip Width), which shows a
reversal of this trend.
Body Segment Lengths
Limb
White Male White Female
(Percentile) (Percentile)
5 th 50 th 95 th 5 th 50 th 95 th
Upper Arm 28.6 30.4 32.3 26.1 27.8 29.5
Forearm 25.9 27.5 29.2 22.7 24.1 25.5
Thigh 40.4 43.2 46.1 36.9 39.5 42.1
Shank 38.9 42.1 45.3 34.7 37.4 40.0
[all values are in centimetres]
L
Joint or HingeSegment
Body Segment Density
Body Segment Year = 1860 Year = 1955
Head and Neck 1.11 g/cm3 1.11 g/cm3
Trunk -- 1.03
Upper Arm 1.08 1.07
Forearm 1.10 1.13
Hand 1.11 1.16
Thigh 1.07 1.05
Lower Leg 1.10 1.09
Foot 1.09 1.10
Density = Mass / Volume Human Segment Density ~ 1 g/cm3
Body Segment Weights
Main Segment as % of Total Body Weight
Individual Segment as
% of Main Segment
Head and Neck = 8.4 % Head = 73.8 %
Neck = 26.2 %
Torso = 50 % Thorax (chest) = 43.8 %
Lumbar = 29.4 %
Pelvis = 26.8 %
One Total Arm = 5.1 % Upper Arm = 54.9 %
Forearm = 33.3 %
Hand = 11.8 %
One Total Leg = 15.7 % Thigh = 63.7 %
Shank = 27.4 %
Foot = 8.9 %
Centre of Gravity
Relative locationof C-of-G’s onbody segments.See the C-of-G%-iles in the nexttable [Dempster, 1955]
Centre of Gravity
Center of Gravity/Segment Length = L1/L2 (%)
Segment Year = 1889
1955 1969
Total Body -- -- 41.2 %
Head -- 43.3 % 46.6
Arm 47 % 43.6 51.3
Forearm 42.1 43 39
Hand -- 49.4 --
Total Arm -- -- 41.3
Forearm & Hand 47.2 -- --
Thigh 44 43.3 --
Calf (= Shank) 42 43.3 37.1
Foot 44.4 42.9 44.9
Total Leg -- 43.3 --
Calf & Foot 52.4 43.7 47.5
C-of-G willnormally be closer
to the “thicker” proximal end
of the segment.
L1 L2
Distal End
Proximal End
[modified from Winter, 1992]
Segment
Head & Neck
C-of-G / SegmentLength
0.50
0.506
0.430
0.436
0.433
0.433
0.500
0.500
Hand
Forearm
Upper Arm
Thigh
Leg
Foot
Trunk
Center of Gravity/Segment Length = L1/L2 (%)
C-of-G willnormally be closer
to the “thicker” proximal end
of the segment.
L1 L2
Distal End
Proximal End
Radius of Gyration/Segment Length = K/L (%)(Cadaver Experiments)
Body Segment From Proximal End
From Distal End
Head, Neck, Trunk 49.7 % 67.5 %
Full Arm 54.2 64.5
Forearm 52.6 64.5
Hand 58.7 57.7
Forearm and Hand 82.7 56.5
Thigh 54 65.3
Shank 52.8 64.3
Foot 69 69
Shank and Foot 73.5 57.2
K
L
Distal End
Proximal End
K
Example – Anthropometric Forearm Data
Purpose• Become accustomed to Generating and Using
Anthropometric Data tables and formulas.Steps (Use ruler or tape measure for length measurement)1. Measure length, L, of forearm (elbow to wrist) and diameter,
d, about half way along length2. Calculate approx. forearm volume, V = (d/2)2L3. Calculate forearm mass, m, in two ways … (do they match?)
• using m = D x V and density from Density Table• using “Body Segment Weights” table
4. Calculate forearm C-of-G using C-of-G/Length ratio table5. Calculate forearm radius of gyration, K, using forearm
length, L, and “Radius of Gyration” table
Forearm Data TableDimension Symbol Value
(female)
Value
(male)
Length L
Closest %ile for Length %
Diameter d
Volume V
Mass (from density formula, D = m/V)
m
Mass (from “Body Segment Weight” table)
m
C-of-G (from elbow) C-of-G
Radius of Gyration
(from elbow)
K
Ergonomic Design Principles1. Designing for the Average• There is no “average” person• Very difficult to find person who is average in more than a few
dimensions (e.g. avg. height may not necessarily mean avg. leg length and arm length)
• Designing for the average can be an over-simplification• Only to be done after careful evaluation (e.g. very specific
subgroup)
e.g. Clothing Study (n = 4096 people)Center 30% was taken as Avg. Percentile, BUT…Only 26% were of Avg. HeightOnly 7.4% had Avg. Chest CircumferenceOnly 3.5% had Avg. Sleeve LengthOnly 0.07% had Avg. Waist CircumferenceAnd 0% had Avg. Foot Length
2. Designing for the ExtremesPrinciple
• Try to accommodate entire population groupMaximum Levels
• e.g. doorways, size of escape hatches on military aircraft, strength of ladders and workbenches
Minimum Levels• e.g. distance of control button from operator, force
required to operate control lever or button Practical Design Range
• use 5th and 95th percentiles of pop. group as extremes• use smallest female and largest male
Questions• Effects on those excluded?• Can we restrict users to a certain pop. group?
3. Designing for AdjustmentPrinciple
• Try to allow for adjustments in size, shape, position, intensity, and duration of the product, device, procedure, or system to accommodate unexpected circumstances
Practical Design Range• Common to use 5th %ile female and 95th %ile male• Results in accommodation of 95% (not 90%) of 50/50
male/female pop. group because of overlap in male and female body dimensions
Examples• Car seats, desk height, footrests, office furniture
Questions• Use: one shot vs. continual?• Use: one user or shared?• Ease of and Training for using “adjustments”?• What happens if design range misused?
Ergonomic Design Approach
1. Determine important body dimensions
2. Define population group (men, kids, Swedes?)
3. Decide on which design principles will be used (design for extremes, average, adjustment?)
4. Select which sub-group of pop. group will be designed for (5th, 50th, 73rd, %ile?)
5. Extract values from Anthropometric Tables
6. Add dimensional allowances for any clothing, equipment, safety precautions, and task performance.
7. Build “prototype” or “mock up” of product, device, procedure, or facility.
8. Test prototype with human subjects.
Sources Used• Chaffin et al., Occupational Biomechanics, 1999.• Dempster, Space Requirements of the Seated Operator,
1955.• Hay and Reid, 1988.• Kreighbaum & Barthels, Biomechanics: A Qualitative
Approach for Studying Human Movement, 1996.• Kroemer, “Engineering Anthropometry”, Ergonomics,
32(7):767-784, 1989• Sanders and McCormick, Human Factors in Engineering
and Design, 1993.• Moore and Andrews, Ergonomics for Mechanical Design,
MECH 495 Course Notes, Queens Univ., Kingston, Canada, 1997.
• Oskaya & Nordin, Fundamentals of Biomechanics, 1991.• Winter, Biomechanics of Human Movement, 1992.