NONLINEAR ADAPTIVE FUZZY CONTROL FOR HYDRAULIC ROBOTS

Abstract –In this paper, a novel adaptive fuzzy controller (AFC) is proposed to deal with the control problem of a parallel robot consisting of a Stewart platform and hydraulic actuators. Specifically, only two signals are measured from the robot system, namely, the leg displacements through Linear Variable Differential Transformer (LVDT) and the current change with Hall sensor. To cope with the difficulty of obtaining the full parametric model of the Stewart platform and that of the complete actuator dynamics, an adaptive fuzzy control method is then adopted. Simulations are done to compare the performance of the presented AFC and that of an appropriately designed adaptive controller. Apparently, the proposed control shows that the tracking errors of the present design are almost an order less than that of the otherwise designed adaptive controller. Copyright © 2005 IFA