Robust control of manipulators using the computed torque plus H∞ compensation method

A new robust control scheme called the computed torque plus H_∞ compensation method is developed to control a robotic manipulator with payload and actuator uncertainties. The method linearises and decouples the nonlinear and coupled dynamic equations of a manipulator by the computed torque approach. Then the remaining uncertainty is compensated by the H_∞ control technique. In the H_∞ control synthesis process the technique of internal weight is applied to select the proper weights. Simulation results indicate that the computed torque plus H_∞ compensation method indeed exhibits better tracking performance than computed torque alone. Indexing terms: Robust control, H_∞ compensation. Robotics