A function description for the human upper limb pointing movements performance

The human motor system is mechanically complex and need to be described by using a large number of degrees of freedom. The controlled operation of such a system requires a reduction of mechanical redundancy. The coordination and synergies among the muscles and joints can be used for the reduction. In this paper, synergy is discussed through the analysis and comparison of human upper-limb pointing movements. All movements were recorded by a Vicon 3D motion analysis system. The synergy in the pointing movement of upper-limb was found among the different joint angles. A function method is used to describe the pointing performance. The different joint angles can be fitted by the same function curve. The pointing movement performance can be determined by the fitting parameter vector and the start and end states. Based on this result, a typical motion pattern can be described by a smaller set of variables.