In this paper, the model-based robotic control problem with disturbance attenuation (or robotic H<FONT FACE=Symbol>¥</FONT> 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 UArm II manipulator, considering fully actuated and underactuated configurations, are presented.
Robust control; nonlinear H<FONT FACE=Symbol>¥</FONT> control; underactuated manipulators