Feedback control of elastic robots by pseudo-linearization techniques

A method to control robots with and without an amount of joint elasticity is presented. The method is based on the pseudolinearization technique. For a two-rotary-joint robot, both a state-feedback control law and an output feedback control law, where the rigid and elastic positions are assumed as outputs, are derived. In the latter case the state vector is reconstructed by an observer that is also designed with the pseudolinearization method. The results of the simulation runs are satisfactory, showing a tracking error in the joint coordinates of the order of 10-**5 rad