Research On Identification Of Motion Elements For The Underwater Target And Search Strategy

UUV is an unmanned submersible capable of performing combat or operational tasks underwater for a long time,and plays an indispensable role in both civil and military applications.When used as an underwater platform,UUV often detects the bearing information of underwater targets by passive sonar carried by itself to identify the moving elements of underwater targets.This thesis focuses on the identification of underwater target motion elements,based on the identification of target motion elements and the optimization of UUV search strategy.The main research contents are as follows:Firstly,for the characteristics of the target moving element only by using the underwater target bearing information,the kinematics models of different motion forms of underwater targets are analyzed,and the system equations and measurement equations in discrete forms are given.The search strategy of UUV under the observable condition of underwater target is analyzed.The performance index of underwater target motion element identification is given,which lays a foundation for the research of subsequent target motion element identification algorithm.Secondly,the identification problem of underwater target motion elements has a high correlation with the research content of nonlinear estimation theory,based on the particle filter algorithm,the research on the underwater target motion element identification is carried out.In order to improve the identification accuracy of target motion elements,an improved extended kalman particle filter algorithm is designed.This algorithm can effectively reduce the influence of particle degradation and depletion on the recognition of underwater target motion elements in particle filter algorithm,and the effectiveness of the improved extended kalman particle filter algorithm is verified by simulation.Thirdly,in the complete target motion element identification for UUV,the measurement accuracy of passive sonar is impossible to improve in a short time,and the identification algorithm used cannot be changed in this identification.At this time,optimization UUV's search strategy has become an important means of improving recognition.Based on the CRLB as the evaluation index,the optimization algorithm of UUV search strategy is designed based on the target of underwater uniform linear motion,and the effectiveness of the UUV search strategy optimization algorithm is verified by simulation.Finally,a typical case is designed.For the target of underwater uniform linear motion and the target of underwater shifting motion,the contrast experiment of target motion element identification is carried out.The target motion element identification algorithm proposed in this paper and the optimization algorithm of UUV search strategy are carried out.The simulation proves that the performance of the underwater target moving element identification is compared and analyzed,and the effectiveness and superiority of the algorithm are proved.The aim is to provide reference for the next engineering application.