Adaptive hierarchical control for uncertain underactuated systems

This paper presents an adaptive controller with wavelet neural network tuner for a class of uncertain underactuated systems. Proposed scheme utilizes the concept of hierarchical structure error surface. Hierarchical structure is obtained by recursive coupling of error surfaces designed for individual subsystems. Error surface coupling is carried out such that the last level error surface includes the error surfaces of all the subsystems. An adaptive control scheme which utilizes wavelet neural network as an adaptive approximator for system uncertainties is proposed to solve the tracking control problem of various subsystems. Stability of integrated error surface and boundedness of closed loop signals is proved in Lyapunov sense. Effectiveness of proposed scheme is illustrated through simulation. low retrieval by CD-ROM software, please include.