Pseudo-reference based on autonomous control system with an orbit attractor

Abstract

For robot-robot or human-human motion instruction, a reference motion pattern is required to show how to move. The reference will be an enhanced motion pattern because of time delay or latency of the closed loop system. In this paper, we propose "Pseudo-reference" that is derived from an autonomous control system based on an orbit attractor. The nonlinear controller is decomposed into a feedback gain and pseudo-reference which is a virtual target posture. Even though the feedback controller is unknown, it can be estimated from the nonlinear controller, and pseudo-reference is obtained. The simulations using an inverted pendulum system show the appropriateness of the pseudo-reference for a reference pattern, and the experiments using a tap dancing robot demonstrates that the estimated controller also leads an appropriate reference pattern. © 2013 The Japan Society of Mechanical Engineers.