One of the important applications for the resolution of redundant mani
pulators is torque optimization, due to the fact that the actuators us
ed for driving a manipulator have finite power ratings. Nevertheless,
not many algorithms have been proposed to accomplish this objective. A
survey of the existing local torque optimization control schemes is g
iven in this article. It will be shown that all of them either encount
er instability problems for long trajectories or fail in certain cases
. For remedying these problems, the authors present the Minimum Veloci
ty Norm (MVN) method, which is the most common approach for kinematic
redundancy resolution and has never been adopted for torque optimizati
on by other researchers. Simulation results show that the simple MVN m
ethod is moderate for short movements and is stable for long movements
. Also, the MVN method can be applied to cases that may not be accompl
ished by some other approaches. Therefore, the MVN method is better th
an the other existing approaches for torque optimization. (C) 1994 Joh
n Wiley & Sons, Inc.