Ergoniza Intelligent

5.3.1 Centers of gravity

Once the model's posture and the mass and center-of-gravity location of each segment are known (the segmental centers of gravity shown in Figure 10), Ergoniza Intelligent calculates the position of the body's center of gravity using the segmental method1. The resulting position is obtained as the weighted average of the segmental center-of-gravity positions, so that each segment's contribution is proportional to its mass.

External loads and moments applied at the hands are not included in the calculation of the body's center of gravity. Their effect is incorporated into the center-of-pressure calculation described in Section 6. Forces applied to other parts of the body are, however, included in the calculation, taking into account the segment and the point on which they act.

Calculating the body's center of gravity from segmental centers of gravity.

Figure 10: Calculating the body's center of gravity from segmental centers of gravity.

Under the conditions considered, the body's center of mass and center of gravity are treated as coincident. To analyze stability, Ergoniza Intelligent represents their vertical projection onto the floor, identified in the interface as the Body Center of Mass (BCM).

  1. D. G. E. Robertson et al., Research Methods in Biomechanics, 2nd Ed. (Human Kinetics Publishers, 2014), doi:10.5040/9781492595809.↩︎

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