Reconfiguration of redundant robots under kinematic inversion

Abstract

We consider the problem of reconfiguring the joints of a redundant robot driven only through end-effector velocity commands. Depending on the chosen kinematic inversion scheme, this system behavior is subject to differential constraints that may be integrable or not. An analogy is established with non-holonomic systems, allowing the use of existing techniques to design cartesian inputs that bring the robot to the desired configuration. Two different control approaches are presented for a robot with a single degree of redundancy, based on the holonomy angle concept and on sinusoidal steering of chained-form systems. Simulation results are reported and generalizations are briefly discussed.