| The integrated design of missile guidance and control system has better performance than the traditional separated design because it can fully consider the coupling information between the guidance system and the control system.Therefore,in order to improve the missile’s hit accuracy,the integrated design of guidance and control system has very important application value.The integrated guidance and control system is a high-order nonlinear system with unknown unmatched interferences and uncertain terms.The design difficulty is how to solve the impact of unmatched interferences and stabilize the system.At the same time,when the states of the system are unmeasurable,the unknown states and the unknown unmatched interferences will constitute the problem of observation dead circulation.In view of the above problems,this paper mainly researches the integrated design method based on sliding mode control and backstepping control.The specific work is as follows:Firstly,the integrated design method of multi-sliding mode backstepping control based on disturbance observer is studied.Taking the backstepping control as the basic framework,the error planes are designed as sliding mode surfaces.Unmatched interference,uncertain nonlinear terms,and the derivative terms of the virtual control law are combined into a comprehensive interference term and observed and compensated by the interference observer.Considering the problem of input limitation,the sliding mode surfaces are improved by the signal exponential recovery method to solve the problem of too large input signal at the initial time.Through theoretical analysis and simulation experiments,the feasibility and effectiveness of this method are verified.Then,considering the observation dead circulation problem caused by the unknown state of the system and the inherent delay problem of backstepping control,the integrated design method based on full-state sliding mode control is studied.The state of the original system is estimated by the measurable input and output signals,and the auxiliary system is designed to visualize the state and transfer the control object.The sliding mode surface is designed,and the control signal is solved by the current system state in one step,which improves the response speed of the system.Finally,in order to further improve the quality of full-state sliding mode control,a new approach law with no chattering and speed controllability was designed by combining constant velocity approach law and power approach law to reduce sliding mode variable structure System chatter.The tracking differentiator is used to design the indirect interference observer that can observe the high-order derivative of interference,which improves the anti-interference ability of the system.The theoretical analysis and simulation experiments verify the feasibility and superiority of the method. |
