Perfect tracking for maximum-phase nonlinear systems by iterative learning control

A method to track a desired trajectory by iterative learning control is proposed for uncertain maximum-phase nonlinear systems. The relation between the variations in the initial state, input and output is derived and it is shown that the inverse mapping from the desired output to the initial state and input is stable using the time reversal of unstable manifolds for a maximum-phase system as given by Doyle et al. Based on these facts, an input update law is proposed to find the initial state and the input for perfect tracking. Also, it is shown that perfect tracking can be made possible over a finite control horizon by using a non-causal input starting at any fixed state. Simulation results show that the proposed method works well.

[1]  C. Melchiorri,et al.  Comparison of noncausal inversion techniques for discrete time linear systems: application to a flexible link , 1998, Proceedings of the 1998 IEEE International Conference on Control Applications (Cat. No.98CH36104).

[2]  Masayoshi Tomizuka,et al.  Experimental flexible beam tip tracking control with a truncated series approximation to uncancelable inverse dynamics , 1994, IEEE Trans. Control. Syst. Technol..

[3]  B. Paden,et al.  Nonlinear inversion-based output tracking , 1996, IEEE Trans. Autom. Control..

[4]  Chong-Ho Choi,et al.  Iterative learning control of nonlinear systems with consideration on input magnitude , 1996 .

[5]  Mingxuan Sun,et al.  An iterative learning controller with initial state learning , 1999, IEEE Trans. Autom. Control..

[6]  B. Paden,et al.  Iterative learning control for nonlinear nonminimum phase plants with input disturbances , 1999, Proceedings of the 1999 American Control Conference (Cat. No. 99CH36251).

[7]  P. Lucibello,et al.  Inversion of nonlinear time-varying systems , 1993, IEEE Trans. Autom. Control..

[8]  Suguru Arimoto,et al.  Bettering operation of Robots by learning , 1984, J. Field Robotics.

[9]  P. Lucibello Inversion of linear square systems by learning , 1991, [1991] Proceedings of the 30th IEEE Conference on Decision and Control.

[10]  J. Grizzle,et al.  Observer design for nonlinear systems with discrete-time measurements , 1995, IEEE Trans. Autom. Control..

[11]  Michael J. Grimble,et al.  Iterative Learning Control for Deterministic Systems , 1992 .