Robust tracking control based on long range prediction

The design and implementation of long-range predictive control for accurate trajectory control of a servo system with a highly nonlinear load are described. The experimental set-up imitates a joint of an industrial manipulator. The control system is implemented around a digital signal processor, which is used to calculate the voltage to be applied to the servo motor. The control algorithm aims for the minimization of a performance index which is chosen as the norm of the tracking error over a future control horizon. For the prediction of the future output, a very simple approach with a physical meaning is followed, and it is shown that this results in the same predicted values as an optimal predictor widely reported in the literature. The experimental results presented show that highly accurate trajectory following is possible in spite of the very simple structure assumed as the model of the servo motor and its nonlinear load