Research On Adaptive Backstepping Control Of Hypersonic Vehicle With Performance Constraint

Hypersonic vehicle has extremely complex characteristics and has become a key research object in the field of aerospace at home and abroad.Due to the complex flight environment and high velocity,the tracking control of hypersonic vehicle still faces many problems.Aiming at the tracking control of hypersonic vehicle under the influence of performance constraint,uncertainty,actuator faults and input saturation,this paper proposes a tracking control strategy based on backstepping control method by using adaptive technology,performance function method,barrier Lyapunov function method and auxiliary system.The main contents are as follows:Firstly,aiming at the tracking control problem of hypersonic vehicle with output error constraint and uncertainty,an adaptive backstepping control strategy with predetermined time prescribed performance is proposed.The hyperbolic cosecant performance function is used to constrained the output error of the system to ensure that the tracking error meets the prescribed performance requirements within the predetermined time.An adaptive law is designed to estimate the upper bound of uncertainty and solve the problem of uncertainty.Based on the dynamic inverse control method and backstepping control method,the controllers are designed for velocity subsystem and altitude subsystem respectively.The bounded stability of the system is proved by Lyapunov theory,and tracking error converges to constrained boundary at the predetermined time.The effectiveness of the control strategy is verified by comparative simulation.Furthermore,considering the tracking control problem of hypersonic vehicle under the impact of output error constraint,actuator faults and uncertainties,an adaptive predetermined time prescribed performance backstepping control strategy is designed.A exponential predetermined time performance function is constructed to deal with the asymmetric constraint of tracking error,and predetermined time prescribed performance controllers are designed for velocity subsystem and altitude subsystem respectively.Adaptive law is used to deal with elevator fault.Combined with prescribed performance function,backstepping control and adaptive technology,a adaptive predetermined time prescribed performance fault-tolerant backstepping control strategy is designed.Based on Lyapunov theory,it is proved that the system is bounded and stable,and tracking error converges to constrained boundary in the predetermined time.Comparative simulation is used to verify the effectiveness of the control strategy.Finally,taking tracking control problem of hypersonic vehicle with full state constraint,input saturation and uncertainty,an adaptive barrier backstepping control strategy is proposed.Through the barrier function,all states are guaranteed to meet the preset constraint.An auxiliary system is constructed to eliminate the problem of input saturation.Adaptive barrier controller and adaptive barrier backstepping controller are designed for velocity subsystem and altitude subsystem respectively.Based on Lyapunov theory,it is proved that the system is bounded and stable,and all states meet the constraint requirements.The effectiveness of the control strategy is verified by comparative simulation.