On adaptive control of flexible joint manipulators: theory and experiments

In this paper we consider a control scheme for manipulators with elastic joints. The proposed algorithm requires only position signals measurements. This algorithm is an extension of the control algorithm proposed by Loria and Ortega (1995). We have assumed that Loria's and Ortega's model has in addition dynamic friction components on both link and motor sides. We have developed for the proposed model of the manipulator an adaptive version of the control algorithm based on Lyapunov stability theory. In a first part of this paper we present a control algorithm in general. We consider two problems of controlling the position of the end effector of the manipulator and tracking control. Simulation and experimental results are presented. The verification of the new algorithm was investigated a simulation way in MATLAB and SIMULINK and at experimental set-up. An experimental set-up consists of a manipulator with two degrees of freedom, and a control system based on a card with signal processor DS 1102. Simulation and experimental results illustrate properties of the new adaptive control algorithm.