Multivariable self-tuning control with decoupling robotic manipulators

The paper presents two self-tuning control schemes for robotic manipulators, based on two canonical multivariable difference models. The controllers are designed such that the variances of generalised cost functions are minimised and the controller parameters are directly estimated. The weighting factors in the cost function can be prespecified in such a form that the manipulator system is decoupled and closed-loop pole assignment is achieved. Simulation results on a robotic manipulator with three degrees of freedom are presented to demonstrate the effectiveness of, and to make a performance comparison between, these two schemes.