Model reference adaptive control of a nonsmooth dynamical system

摘要

In this paper a modified model reference adaptive control (MRAC) technique is presented which can beudused to control systems with nonsmooth characteristics. Using unmodified MRAC on (noisy) nonsmoothudsystems leads to destabilization of the controller. A localized analysis is presented which shows that theudmechanism behind this behavior is the presence of a time invariant zero eigenvalue in the system. Theudmodified algorithm is designed to eliminate this zero eigenvalue, making all the system eigenvalues stable.udBoth the modified and unmodified strategies are applied to an experimental system with a nonsmoothuddeadzone characteristic. As expected the unmodified algorithm cannot control the system, whereas theudmodified algorithm gives stable robust control, which has significantly improved performance over linearudfixed gain control.ud