c © 1997 Kluwer Academic Publishers. Printed in the Netherlands. Adaptive Impedance Control Applied to a Pneumatic Legged Robot

Abstract. An adaptive impedance control scheme with estimation of robot and environment param-eters is proposed in this paper. It consists of two stages of adaptation and control. The first one performs an on-line estimation of the robot inertial parameters, during the complete (constrained or not) motion of the leg, while the second one compensates for the uncertainties on the charac-teristics of the ground (position and stiffness). Simulation results obtained for a single leg of a pneumatic driven, quadruped robot show the effectiveness of the proposed control scheme in case of considerable uncertainty both in the robot and ground parameters. Key words: adaptive impedance control, passive feedback systems, robust control, pneumatic legged robot. 1