Design of Controls Using Force as a Criterion

Abstract

A force platform was used to study the effect of varying the height and handle orientation of a push-pull task. Each of the ten subjects performed the task at knee, hip, waist, chest, and eye heights and at each of the heights the handle was oriented in five different positions. Even though the force required for the task itself did not vary, changing the height of the handle forced each subject to exert a force to maintain his own body position. This force exerted by the subject was minimized when the handle was at chest height. The only previous studies on optimum work heights have concerned work surface location. Since their usual recommendations are to place a work surface below rather than above the elbow, it seems additional experimentation is desirable.