A globally stable saturated desired compensation adaptive robust control for linear motor systems with comparative experiments

This paper integrates the recently proposed saturated adaptive robust controller with desired trajectory compensation to achieve global stability with much improved tracking performance. The algorithm is tested on a linear motor drive system which has a limited level of control effort and is subject to parametric uncertainties, unmodeled nonlinearities, and external disturbances. Global stability is achieved by employing back-stepping design with bounded (virtual) control input in each step. A guaranteed transient performance and final tracking accuracy is achieved by incorporating the well-developed adaptive robust controller with effective parameter identifier. The noise effect is further alleviated by replacing the noisy velocity signal with the cleaner position feedback when implementing the adaptation function. Furthermore, asymptotic output tracking can be achieved when only the parametric uncertainties are present