Attitude Fault-Tolerant Control Of Hypersonic Vehicle Based On Extended State Observer

Hypersonic vehicles are widely employed in military fields because of their fast flight speed and high combat capability.The flight environment of a hypersonic vehicle is complex and variable,and its mathematical model has strong coupling,strong nonlinearity,and strong uncertainty,which makes the design of the controller more difficult.In addition,the possibility of system failure increases during flight due to frequent actuator action.Therefore,a six-degree-of-freedom dynamics model of the hypersonic vehicle is used as the object of study,and the following aspects of research are carried out.1 、 Attitude fault-tolerant control design for hypersonic vehicles with active disturbance rejection control.Firstly,the dynamics model of hypersonic vehicle is given,and an attitude angleoriented control model is developed.Secondly,The extended state observer is used to estimate and compensate the unmodeled dynamics,inter-channel coupling,parameter uncertainties,and external environmental disturbances.Then the corresponding error feedback control law is designed.The simulation results show that the proposed strategy has good control performance under three conditions: no disturbance,added disturbance,and actuator failure.2、Neural network sliding mode attitude fault-tolerant control design for hypersonic vehicles based on extended state observer.A fault tolerant attitude control method of neural networks based on extended state observer is proposed.Firstly,the extended state observer is employed to estimate and compensate the total disturbances.Secondly,the attitude control law is designed by combining the neural network minimum parameter learning method,and the closedloop stability analysis is completed with the Lyapunov theory.Finally,the simulation results show that the proposed control strategy has better control performance.3、Neural network attitude fault-tolerant control design for hypersonic vehicles based on super-twisting extended state observerAn adaptive fault-tolerant control scheme based on a super-twisting extended state observer is proposed,which employs a finite-time convergence control method instead of the traditional asymptotic convergence method.Firstly,the super-twisting extended state observer is utilized to estimate and compensate for the total perturbation of each channel.The error processing of attitude control is realized by combining the adaptive algorithm and the neural network minimum parameters.Secondly,the finite-time stability of the closed-loop system is proved by the Lyapunov function.Finally,the simulation results show that the designed control algorithm improves the antidisturbance performance of the hypersonic vehicle.