The Relationship between Hand Force Direction and Posture during Two-Handed Pushing Tasks

Abstract

Posture and external loads such as hand forces have a dominant effect on ergonomic analysis outcomes. Accurate job analyses require accurate representation of working postures and knowledge of external loads. The effects of hand force location, magnitude, and direction on whole-body posture for standing tasks were quantified in a motion-capture study of 20 men and women with widely varying body size. A subset of the data was analyzed to study the relationship between hand force direction and posture during two-handed pushing tasks performed with and without a constraint on hand force direction. Analyses demonstrated that force direction is a significant determinant of posture, and that pushing postures are consistent with several biomechanical principles.

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