Prescribed performance safe tracking control for the unmanned helicopter with input and output constraints
This paper deals with the problem of prescribed performance safe tracking control for the attitude and alti-tude system of unmanned helicopter with unknown external disturbances,input saturation,and constraints of attitude and altitude.Firstly,by considering the constraints of attitude and altitude,a safe desired tracking signal is constructed with the application of an output boundary protection algorithm.Furthermore,combining with the proposed output boundary protection algorithm,the prescribed performance function is developed to guarantee the tracking performance of the safe desired tracking signal.A Sigmoid function is utilized to tackle the problem of saturation input.To compensate the com-pound disturbances which include external disturbances and the estimation error of Sigmoid function,a parameter adaptive method is adopted to approximate its upper bound.Combining with the backstepping technology,the safe tracking con-troller is investigated.The Lyapunov stability theory is employed to guarantee the boundedness of all closed-loop signals and the safe tracking performance of the unmanned helicopter system.Simulation results of an example are provided to illustrate the effectiveness of the proposed control scheme.
万方数据
维普
