Research On Imaging Distortion Correction Of Linear Array Lidar For Space Instability Target

The space instability targets include the fault spacecraft,space garbage,and failure satellite and so on.The non-cooperative space instability target brings great threat to the spacecraft and astronauts because of its uncontrolled characteristics.Therefore,the requirement of the orbit capture,maintenance and cleaning of the space instability target is very tight,and target 3D measurement technology is one of the key technologies to solve the problem.In recent years,Lidar has become the first choice of space target measurement tools in the field of space technology due to its small influence on light and distance,and strong ability to resist active jamming.The common imaging methods include line form and surface formation.In the space operation,the surface array Lidar is limited by the number of elements in the array element.The linear array Lidar has a higher imaging resolution than the surface array Lidar,and the load of the space spacecraft is small.And the acquired line array data can also be used for motion parameter estimation and three-dimensional pose measurement.The research on linear array Lidar imaging technology for space instability targets is currently in its infancy.Data acquisition is relatively cumbersome,and the selection of Lidar parameters needs to be studied.At the same time,due to the relative motion relationship between the linear array Lidar and the space instability target,the Lidar imaging is distorted,and the obtained target topography information is distorted.This dissertation focuses on the method of distortion correction of linear array Lidar for space instability target.Firstly,the motion characteristics of the space instability target and the imaging mechanism of the linear array Lidar are studied.From the relative motion relationship between the Lidar and the target,the reason of Lidar imaging information distortion is analyzed.Then,the imaging modeling for space instability targets and parameter optimization of linear array Lidar are realized,including the proposed target spin motion model and nutation motion model,the identification of target surface visible point,Lidar imaging modeling algorithm,and proposed Lidar parameter optimization method and analysis of the influence of Lidar parameters on the assessment of target acquisition integrity.Finally,the method of distortion correction of the linear array Lidar imaging information for space instability targets,the calibration method uses the target topography feature to obtain the target motion parameters,and apply the target motion mathematical model in reverse to transform each group of linear array information at different times of the Lidar to the same time.That is to say,linear array information is reassembled to achieve the purpose of correcting Lidar imaging distortion information.The experimental results show that the error between the target motion parameters from the correction algorithm of this dissertation and the target motion parameters set by Lidar imaging modeling is less than 1°/s.In addition,the degree of curvature of the target solar panels edge in the Lidar imaging information after correction is up to the standard.Therefore,the proposed method of distortion correction of linear array Lidar for space instability target is feasible.At the same time,it can also provide technical reference for other linear-array measurement techniques of different forms of motion targets.