Robot arm dynamic control by computer

A new dynamic control method is discussed for robot arms. It is based on nonlinear feedback and diffeomorphic (state) transformation which externally (or exactly) linearizes the whole system and provides simultaneous output decoupling. The non-linear feedback is augmented with optimal error correcting controller, which operates on the task error level. Several computer simulations were performed to evaluate the performance of the new dynamic control method. The simulation results are discussed in detail. The simulations show that the new dynamic control method provides very good tracking performance even in cases when the dynamic model parameters of the robot arm are only known with 10-30% error. The functional characteristics of the nonlinear feedback law and optimal error correcting controller are discussed briefly.