Vibration suppression control of constrained spatial flexible manipulators

For free motions, vibration suppression of flexible manipulators has been one of the hottest research topics. However, for constrained motions, little effort has been devoted to vibration suppression control. Using the dependency of elastic deflections of links on contact force under static conditions, vibrations for constrained planar two-link flexible manipulators have been suppressed successfully by controlling the contact force. However, for constrained spatial multi-link flexible manipulators, the vibrations cannot be suppressed by only controlling the contact force. So, the aim of this paper is to clarify the vibration, mechanism of a constrained, multi-DOF, flexible manipulator and to devise the suppression method. We apply a concise hybrid position/force control scheme to control a flexible manipulator modeled by a lumped-parameter modeling method. Finally, a comparison between simulation and experimental results is presented to show the performance of our method