Robust adaptive tracking control for full state-constrained nonlinear systems with unknown control direction
WANG Chun-xiao
WU Yu-qiang
Abstract：To consider a class of full state-constrained nonlinear systems with completely unknown control coefficients, uncertain time-varying parameters and disturbances, a Barrier Lyapunov function (BLF) based adaptive robust control design method is proposed.BLFs are to ensure that the full state constraints be not violated,the unknown control direction is resolved effectively by the Nussbaum gain function and the boundedness of uncertain time-varying parameters is guaranteed by using the continuous projection algorithm. It is the first time that the BLF,Nussbaum gain function and continuous projection algorithm effectively combine with backstepping adaptive control to solve the tracking control problem for full state-constrained nonlinear system with unknown control direction. As shown as the control result, all the closed loop signals are bounded and full state constraints are not violated. Moreover the system output tracking error will converge to a bounded compact set of zero through select proper parameters.At last,The effectiveness of the proposed control scheme is further verified with a numerical example.
Keywords：barrier Lyapunov functionNussbaum gain controlunknown control directionfull state constraintsadap-tive control
Publication Date：2018-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 153-161 )