Robust model free adaptive control with measurement disturbance

This study discusses the robustness of model free adaptive control (MFAC) algorithms. It is shown that the robust stability of MFAC system with bounded measurement disturbance can be guaranteed, and the bound on tracking error depends on the bound on the measurement disturbance. The statistical analysis approach is also introduced to investigate the influence of measurement disturbance. Then, a modified MFAC algorithm with decreasing gain is proposed. Theoretical analysis indicates that the proposed algorithm can attenuate measurement disturbance effectively and obtain better output performance. The analysis is supported by simulations.