Research On Key Technologies Of Space Situational Awareness Based On Binocular Vision Satellite Formation

Space situational awareness includes the detection,tracking,and identification of space targets,and the evaluation and prediction of space events.It is the basis for understanding and responding to space threats and ensuring space security.Space-based space situational awareness systems can be divided into integrated single-star platforms and distributed multi-star platforms,the latter of which has the advantages of large-scale spatial and three-dimensional comprehensive observations,and is the future development trend.This article focuses on non-cooperative target tracking in distributed formations.The research is based on the binary star formation system to realize the positioning and tracking of non-cooperative targets within 100 km.The visible light camera installed on a single star is used to image the target synchronously.The dynamic equation of the target star orbit is established.The relative position information obtained by binocular vision positioning is used instead.Angle measurement information enables high-accuracy and fast tracking of noncooperative targets in space.The main research results of the paper are as follows:(1)Based on the constraints of the imaging system,a non-cooperative target within 100 km was constructed,and a variable external parameter binocular model error transmission algorithm was constructed,and the core indicators of the binocular formation system were evaluated,including the baseline requirements of the binocular formation,the focal length of the visible light camera,Field angle,target centroid extraction accuracy,and attitude measurement accuracy,etc.,complete the selection and design of the system scheme.(2)Analyze the configuration requirements of the positioning algorithm for the double-star formation,including the shortest baseline length,baseline stability,and baseline measurement accuracy,etc.,and study the double-star formation configuration design method,and use the nonlinear optimization algorithm to improve the influence of J2 perturbation.Stability of Double Star Formation.For a formation baseline with a design value of 100 m,the method optimizes the baseline drift amplitude from 28.1166 m to 4.4047 m.(3)A non-cooperative target tracking method based on the binocular formation external reference self-calibration method is proposed,and the self-calibration of the binocular camera relative to the external reference is achieved using a pose sensor.The results show that the selfcalibration method corrects the positioning deviation caused by the non-fixed external parameters of the binocular camera,and achieves high-accuracy fast target tracking without initial track determination.The target three-axis positioning error within 100 km is controlled in the order of 10 m,the speed measurement error is controlled within 10 m / s,and the convergence time is better than 100 s.In summary,by modeling the error of the non-cooperative targets of the double star formation,this paper gives a formation configuration design and optimization method that meets the requirements,and solves the positioning deviation introduced by the fixed external parameters of the binocular camera.A space-based space situational awareness technology solution based on the double-star formation was proposed,and the effectiveness of the method was evaluated through simulation verification,which provided a certain reference for the subsequent construction of a space-based distributed situational awareness system.