Adaptive H∞ approach based on energy-shaping for robotic force/position regulation and motion control

An adaptive H_∞ SP-D (saturated proportional and differential) control law is proposed for robot manipulators interacting with a compliant environment. The proposed control law is derived from a concept of energy-shaping. It achieves both motion control on a contact plane of the environment and force/position regulation along a perpendicular direction to the plane, simultaneously. Furthermore, disturbance attenuation is analyzed by exploiting an L₂-gain of the manipulator system. The energy-based control approaches for manipulators such as the Lyapunov-based method and the passivity-based method have attracted much attention. In order to investigate for essences of the energy-based control, the concept of energy-shaping is useful. The contribution of the article is to research into some abilities of the energy-shaping control for manipulators in contact with the compliant environment