Adaptive backstepping with a high-order tuner

The paper proposes a new type of adaptive backstepping design. At each step of the design procedure a virtual control directly counteracts the transie nts of adjustable parameters, while the time derivatives of these parameter s up to the desired order are generated by a special adaptation law (high-o rder tuner) defined at the final step. Thus, the proposed approach combines adaptive backstepping with high-order tuners. The resultant control law do es not involve tuning functions and, at the same time, is free of overparam etrization. (C) 2001 Elsevier Science Ltd. All rights reserved.