Research On Measurement Of Relative Pose Between Space Non-cooperative Targets Based On Vision And Laser

Relative navigation between non-cooperative spacecrafts is an important subject in the field ofon-orbit service. In this issue, the measurement of relative pose between non-cooperative spacecraftsis the key to realize relative navigation. The relative pose measurement between non-cooperativetargets based on vision and laser is studied in this thesis.Firstly, aiming at the problems of complicated calibration process, needing specially designedcalibration board and calculation complexity in traditional methods, a new method based on featurepoints matching of natural scene for joint calibration of camera and laser is proposed. First, the laserpoints and image pairs are acquired respectively, and the corresponding feature points are selected.Then, the extrinsic calibration parameters are obtained by matching feature points. Finally, thethree-dimensional reconstruction of the scene is achieved. Compared with checkerboard-basedcalibration method, experimental results indicate that the proposed method can not only improve thecalibration precision by83%, but also simplify the calibration process.Secondly, a stereo vision-based method is discussed to measure the relative pose betweennon-cooperative spacecrafts. This method neither needs the corner reflectors or luminous signs whichare used for aided measuring, nor needs the knowledge of the target’s geometry size. The spacecraftwindsurfing is used as the identification target. The four pose measurement results are obtained byextracting four feature points, and the average of the results is regarded as the pose relative to thetracking spacecraft. Computer simulation and semi-physical simulation results indicate that the poseerror of the method is less than1.5°, and the precision is improved by15%.Finally, according to the fact that vision technology is susceptible to lighting conditions, lack offeatures and low contrast, the new method based on stereo vision and laser scanning is proposed. Theselection of sensors, the designing of hardware and the workflow of system are also studied.Meanwhile, the pose measurement method based on visual and laser is proposed. The methodcombines the advantages of vision and laser to achieve high precision and can adapt to differentillumination conditions, which can provide a new method for measurement of relative pose betweennon-cooperative targets in space.