Research On Near Space Hypersonic Target Tracking Technology

In recent years,with the rapid development of Near Space Hypersonic Vehicles(NSHVs),the detection and tracking of high-speed and high-maneuvering targets has gradually become a hot issue in academic and engineering research.Conventional maneuvering target tracking methods can achieve better tracking results in scenarios where the target is weak and the model parameters are known.However,the NSHVs have characteristics of long-distance,ultra-high-speed and strong maneuvering,which lead to great uncertainty in the target movement.If the traditional maneuvering target tracking methods are adopted,the tracking accuracy will be reduced due to the model mismatch,and even the filtering will fail.Therefore,in order to meet the urgent needs of high-precision,strong-robustness and real-time performance of NSHVs,this paper takes the trajectory of the gliding segment of NSHVs as the research object,and conducts in-depth research on its tracking methods.The main contents include:Firstly,starting from the dynamic model of NSHVs,the necessity of modeling and filtering algorithm design for high-speed and high-maneuvering targets is derived.At the same time,a detailed introduction of typical maneuvering target tracking models and filtering algorithms is given,and the applicable scope of different models and filtering algorithms is compared and analyzed through simulation experiments.Nextly,the trajectory of gliding segment of NSHVs is analyzed,and the tracking model combining‘kinematics and dynamics’is established.Through the dynamic decomposition of the trajectory of aircraft,the typical longitudinal and lateral motion patterns are obtained.The model combining"damping oscillation"and acceleration is used to deal with the longitudinal motion with actuator failure;the Sine-CS model is used to deal with the lateral maneuvering.Moreover,and the effects of parameters such as state dimension and model number on the tracking models are discussed.Simulation experiments shows that the proposed model can significantly improve tracking performance of high-speed and high-maneuvering targets,and the tracking accuracy is increased by more than 3 times when actuator fault occurs.Aiming at the nonlinear measurement problem introduced by Doppler Radar,an augmented IMM filtering algorithm based on pseudo-doppler state measurement is proposed,which can correct the nonlinear conversion deviation and achieve better filtering effect.Then,for the situation where noise characteristics are unknown,an improved IMM algorithm based on the H_∞filtering theory is proposed to ensure the best performance estimation in the case of noise uncertainty.It can be seen from the simulation analysis that the filtering accuracy of the proposed filtering algorithm is increased by more than 2 times,and it also has stronger robustness.In addition,due to the arbitrary switching of the maneuvering mode of aircraft,the maneuver detection and fault identification algorithms are designed on the basis of the state observability analysis,which ensures the real-time tracking after the maneuver occurs.