An inter-segment allocation strategy for postural control in human reach motions revealed by differential inverse kinematics and optimization

This paper describes a unique approach to represent the postural control strategy in human motion as a strategy of allocating effort among body segments. With differential inverse kinematics, this approach quantifies the inter-segment allocation using a set of weighting parameters. The parameter values are estimated through optimization procedures based on simulated annealing such that the reproduced movement profiles best emulate the measured ones. An illustration is provided by testing the approach against experimental seated motion data. Results show that accurate reproductions of measured movements can be achieved, while different strategies during distinctive types of motions are revealed by the relative magnitudes of weighting parameters.