Tracking of High Acceleration Movements With a Pneumatic Impedance Controller

Abstract

An original structure to simulate the vertical dynamic jump of one leg is proposed in this paper. The aim is to reproduce a motion composed of an upward propulsion, a flying and a landing phase. The leg is modeled as a three rigid body moved by three pneumatic actuators. A dynamic model of the structure is first presented and the design of the impedance controller is developed based on the nonlinear control theory. The originality of the controller lays in the consideration of impedance behavior at each joint during free and constrained phases. The asymptotic stability is ensured using Popov criteria. The simulations proposed are based on physiological data coming from experiments of a human performing a jump. This specific motion will show the performances of the controller especially during the propulsion and the landing phases because of their high acceleration characteristics.