Digital human model simulation of fatigue-induced movement variability during a repetitive pointing task

Abstract

Movement variability is an essential characteristic of human movement. It occurs in all kinds of activity including work-place tasks. However it is almost ignored in workstation design, where expected movements are highly standardized for productivity and quality considerations. Neglecting this variability may lead designers to omit parts of the future operator’s movements, thus leading to incomplete assessment of biomechanical risk factors. This article describes a model-based virtual human controller intended to simulate the movement variability induced by muscle fatigue during a repetitive activity. It is built using a multibody dynamics framework and a 3-compartments muscle fatigue model. The simulation of a repetitive pointing activity is described. Our demonstrator reproduces some of the adaptive behaviors described in the literature. This demonstrator must still be validated by experimental human data, but it opens interesting perspectives for DHM software improvements and more reliable ergonomic assessments from the early stages of workstation design.