Adaptive control of a class of nonlinear systems using multiple models with smooth controller

SummaryThe idea of using multiple models to improve transient performance in adaptive control systems with large uncertainty or time varying parameters was introduced in 1990s. However, the commonly used scheme with switching has some potential drawbacks. In this paper, a new multiple model scheme is proposed for strict-feedback nonlinear systems. In order to avoid the possible chattering resulted from the controller's switching, a continuous controller based on the convex combination of parameter estimates of identification models is presented, which ensures the better use of the information of identification models than the switching scheme. Also, the number of necessary models is just one more than the dimension of the unknown system parameter, which is more practical. Simulation studies are presented to demonstrate the efficiency of the proposed scheme.