H-infinity robust control design for an arm manipulator
This paper deals with the application of the optimal H-infinity control design technique to derive a controller for a 3 DOF arm manipulator affected by nonmodeled dynamics, nonlinearities, actuator dynamics and sensor noise. The control objectives were to obtain a robust stable with robust performance controlled system. A family of nonparametric models for a finite number of the arm configurations was obtained. Then, a multivariable nominal model was proposed and derived together with additive nonparametric uncertainty bounds. Weighting functions were used to normalize the H-infinity norm of the uncertainty and to act on the command, sensor, and error signals. Finally, a controller was computed by solving the corresponding H-infinity optimization problem. The controller was tried on the nominal and worst case configuration models. The results showed robust stability and robust performance of the controlled system.
robust performance nonparametric model weighting functions robust stability additive unstructured uncertainty