Optimal control of a flexible manipulator and controller order reduction

Presented is a control system design study for a flexible manipulator consisting of a DC electric motor drive connected via flexible links to an end effector. Output feedback H₂ and H _∞ control are synthesized. The resulting controller is high order for implementation and so controller order reduction methods are considered. It is shown, for this plant and with good theoretical choices for controller reduction weights, that it is difficult to reduce the controller order beyond a nominal amount without significantly compromising performance. A reason for this is postulated using perturbation models