Two-arm manipulation: what can we learn by studying humans?

This paper addresses determination of trajectories and force distribution for cooperative manipulation with two arms through optimizing an integral cost function that depends an the actuator forces. We compare the calculated trajectories with the measurements on human subjects performing planar manipulation tasks. Our findings suggest that the trajectories and forces used by humans can be predicted by minimizing the integral of the rate of change of actuator torques over the trajectory. Good match is shown for a class of manipulation tasks in which the person-to-person variability is small. The theoretical foundation for computing the optimal solutions is briefly presented and the advantages of using such schemes for robotic systems are discussed.