Research On Vision-based Relative Position And Attitude Measurement Technology For Close-range Spacecraft

As more and more space vehicles are sent into space,rendezvous and docking technology of space non-cooperative target spacecraft is becoming more and more important.This paper focuses on the research of vision-based relative pose measurement technology for short-range spacecraft.Based on the analysis of the research status and trends of monocular vision measurement technology at home and abroad,several key issues such as camera calibration,feature extraction,target location and relative pose determination are studied.Firstly,this paper analyses the calibration method based on moving plane template.This method can not only get the important parameters from two-dimensional image to three-dimensional,but also eliminate the distortion caused by the lens.The experimental results show that the algorithm has high accuracy.Secondly,this paper proposes Otsu threshold segmentation method and ellipse detection method based on artificial bee colony algorithm.The elliptical docking ring is separated from the image and the coordinate information of the feature points on the ellipse of the docking ring is extracted,which provides solid basic information for subsequent target location and relative pose measurement.Finally,a method of pose measurement based on flight marker is proposed.On the basis of easy extraction of the feature points of the center of the docking ring and easy identification of the flight marker,the relative pose accuracy obtained is higher.In addition,this paper also designs a method to determine the position of the flight marker on the target spacecraft.Compared with the actual relative attitude,the error is always within 2°,so it can be used as an effective method for relative attitude measurement of target spacecraft.