Nonlinear H∞ control for underactuated manipulators with robustness tests

Abstract

In this paper, the model-based robotic control problem with disturbance attenuation (or robotic H∞ control problem), presented in Chen et all (1994), is extended to underactuated manipulators. The dynamic coupling between the links is used to control all manipulator's free joints. A global explicit solution is found solving a minimax Bellman-Isaacs equation, generated via differential game theory. Experimental results, obtained from U Arm II manipulator, considering fully actuated and underactuated configurations, are presented.