TIME-SCALING CONTROL OF AN UNDERACTUATED MANIPULATOR

Position control of an underactuated manipulator that has one passive joint is investigated. The dynamic constraint caused by the passive jo int is second-order nonholonomic. Time scaling of the active joint tra jectory and bidirectional motion planning from the initial and the des ired configurations provide an exact solution of the positioning traje ctory. The active and passive joints can be positioned to the desired angles simultaneously by swinging the active joints only twice. Feedba ck control constrains the manipulator along the planned path in the co nfiguration space. Simulation and experimental results show the validi ty of the proposed methods. (C) 1998 John Wiley & Sons, Inc.