Research On Missile Terminal Guidance Based On Non-smooth Control

As a modern weapon,the missile can achieve long-distance and high-precision mission through the guidance system.So,it has become the national defense force weapon.At the terminal stage of the guidance,the time left to precision is very short,and the targets often have large maneuvering.Therefore,the performance at this stage will ultimately determine whether the missile can successfully hit the target and achieve the goal of attack mission.During the terminal process,expect for the target manervering,the autopilot dynamic,the terminal impact angle constraint and the output constraint are the important factors during the terminal guidance.Therefore,the above factors are taken into consideration in this paper to improve the missile guidance precision.In this paper,the planar and the three-dimensional terminal guidance problem of the missile intercepting the maneuvering target is studied based on the non-smooth control method.The main results can be abstracted as follows:The planar terminal guidance problem of missile intercepting maneuvering target problem is studied based on adding a power integrator method.Firstly,the terminal impact angle constraint is taken into consideration,and a nonlinear disturbance observer is used to estimate the target maneuvering information.Terminal guidance law is designed using adding power method.Then,the dynamic of the missile autopilot is taken into consideration.Terminal guidance law is designed using adding power method,in which the target acceleration has the boundness.Considering the terminal impact angle constraint and the missile autopilot dynamics,aiming at the three-dimensional terminal guidance system,the terminal guidance law of three-dimensional space is designed combining the barrier Lyapunov function and adding a power integrator method with the line-of-sight constraint.Firstly,decouple three-dimensional space into two channels: azimuth channel and pitching channel.Then taking the terminal impact angle constraint into consideration,adding a power integrator guidance law is designed on azimuth channel and pitching channel,respectively.This paper further takes the autopilot dynamic and LOS angle constraint of the missile into consideration,adding a power integrator guidance law is designed.Aiming at the characteristics that the guidance instruction response has the discrete working mode,a feedback controller based on the output sampled-data method is designed.First of all,supposed that the parameter information of the system can be accurately measured.The full-order observer is used to estimate the system state information,and combined the output sampled-data method design the discrete terminal guidance law.However,the state information in the system is difficult to measure accurately in practice,for example,the relative distance between missile and target.But the upper and lower bounds of the parameters are known.Besides,the output is known,so the reduced-order observer is used to estimate the other state information.The terminal guidance law of the missile guidance system is designed by using the bound of the parameters and combining with the the output sampled-data feedback control.Finally,the simulation results show the effectiveness of the proposed control method.