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Overview
The geometric human
body model designed by Hanavan (1964) was modified as follows:
 | The segment masses were estimated based on the
regression equations of Clauser et al. (1969) instead of those of
Barter (1957). This was
originally tried by Miller & Morrison (1975). |
| The trunk was divided into three segments at the
omphalion (navel) and xyphion level: upper
(elliptical column), middle (elliptical solid) and lower (elliptical column). |
| The hand was defined as an ellipsoid of
revolution. |
| The foot was defined as an elliptical solid with
the base (proximal end) being circular. |
| The thigh was defined as an elliptical solid with
the top (distal end) being circular. |
A total of 41 anthropometric parameters need to be measured in this model (Table 1).
TABLE 1. Anthropometric Parameters Used in the
Modified Hanavan Model
| No |
Parameter |
No |
Parameter |
| 1 |
Length, Hand |
21 |
Circumference, Toe |
| 2 |
Length, Wrist to Knuckle |
22 |
Circumference, Ankle |
| 3 |
Length, Forearm |
23 |
Circumference, Shank |
| 4 |
Length, Upperarm |
24 |
Circumference, Knee |
| 5 |
Length, Elbow to Acromion |
25 |
Circumference, Upper Thigh |
| 6 |
Length, Foot |
26 |
Circumference, Head |
| 7 |
Length, Shank |
27 |
Circumference, Chest |
| 8 |
Length, Thigh |
28 |
Circumference, Xyphion Level |
| 9 |
Length, Head |
29 |
Circumference, Omphalion Level |
| 10 |
Length, Upper Trunk |
30 |
Circumference, Buttock |
| 11 |
Length, Xyphion to Acromion Level |
31 |
Width, Hand |
| 12 |
Length, Middle Trunk |
32 |
Width, Wrist |
| 13 |
Length, Lower Trunk |
33 |
Width, Foot |
| 14 |
Circumference, Fist |
34 |
Width, Toe |
| 15 |
Circumference, Wrist |
35 |
Depth, Hip |
| 16 |
Circumference, Forearm |
36 |
Width, Chest |
| 17 |
Circumference, Elbow |
37 |
Width, Xyphion Level |
| 18 |
Circumference, Axillary Arm |
38 |
Width, Omphalion Level |
| 19 |
Circumference, Foot |
39 |
Width, Coxae |
| 20 |
Circumference, Ball of Foot |
40 |
Length, Xyphion Level to Chin/Neck Intersection |
| 41 |
Length, Hip to Chin/Neck Intersection = P12
+ P13 + P40 |
Top
Mass Computation
The masses of the segments were obtained from the
prediction equations of Clauser et al. (1969) while the densities of the segments were
calculated from the masses and the volumes of the segments in this method. Each segment was defined as a simple geometric shape and
the density throughout the segment was assumed to be constant.
TABLE 2. Mass Prediction Equations
(Adapted from Clauser et al, 1969)
| Segment |
Prediction Equation |
| Hand |
m = 0.038*P15 + 0.080*P32
- 0.660 |
| Forearm |
m = 0.081*M + 0.052*P16 -
1.650 |
| Upperarm |
m = 0.007*M + 0.092*P18 +
0.050*P5 -3.101 |
| Foot |
m = 0.003*M + 0.048*P22 +
0.027*P6 - 0.869 |
| Shank |
m = 0.135*P23 - 1.318 |
| Thigh |
m = 0.074*M + 0.138*P25 -
4.641 |
| Head |
m = 0.104*P26 + 0.015*M -
2.189 |
| Trunk |
m = 0.349*M + 0.423*P41 +
0.229*P27 - 35.460 |
M = whole-body mass Pi
= anthropometric parameter shown in Table 1
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Modeling
As shown in Figure 1,
the hand and head were defined as ellipsoids of revolution while other body segments were
defined as variations of elliptical solid such as truncated circular cones (forearm,
upperarm and shank), elliptical columns (upper trunk and lower trunk), elliptical solid
(middle trunk), or elliptical solids with one face being circular (foot and thigh). See
Table 2 for the details.
Figure 1
TABLE 3. Geometric
Shapes and Arguments of the BSP Functions
| Segment |
Geometric Shape |
Group |
Arguments of the BSP Functions |
| Hand |
ER |
SE |
 |
| Forearm |
TCC |
ES |
 |
| Upperarm |
TCC |
ES |
 |
| Foot |
ES with
Circular Base |
ES |
 |
| Shank |
TCC |
ES |
 |
| Thigh |
ES with
Circular Top |
ES |
 |
| Head |
ER |
SE |
 |
| U Trunk |
EC |
ES |
 |
| M Trunk |
ES |
ES |
 |
| L Trunk |
EC |
ES |
 |
EC = Elliptical Column, ER =
Ellipsoid of Revolution, ES = Elliptical Solid,
SE = Semi-Ellipsoid, TCC = Truncated Circular Cone
Pi = anthropometric parameter shown in Table 1
a, ao, a1, b, bo,
b1, c & L = symbols used in the BSP equations
The whole trunk mass is calculated from the
prediction equation while those of the individual segments are calculated based on the
volumes and the density factors (0.92 for the upper trunk and 1.01 for both middle and
lower trunks) of the trunk segments:
[1]
where UT, MT & LT
= upper, middle & lower trunk, respectively, m = mass, V = volume,
and sf = scaling factor. The BSP estimation procedures are as follows:
| Computation of the segment masses using the
prediction equations in Table 2 |
| Computation of the segment volumes and CMs using
the BSP functions (Table 3) |
| Computation of the masses of the trunk segments
using [1] |
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References and Related Literature
Barter, J. T. (1957). Estimation of the mass of body segments.
WADC-TR-57-260. Wright-Patterson Air Force Base, Ohio.
Hanavan, E. P. (1964). A mathematical model of the human body.
AMRL-TR-64-102, AD-608-463. Aerospace Medical Research Laboratories, Wright-Patterson Air
Force Base, Ohio.
Miller, D. I. and Morrison, W. (1975).
Prediction of segmental parameters using the Hanavan human body model. Med. Sci. Sports 7, 207-212.
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