Research And Implementation Of Relative Pose Measurement Method For Ring Target

Human beings have never stopped exploring space and the increasing space activities in the near future.For example,the establishment of the Beidou satellite navigation system in China has brought great convenience to human production and life,and has injected new impetus into global economic and social development.Vitality.However,frequent near-Earth space activities have also brought about a series of problems.Due to the limited resources of the geo Earth orbit,the satellites that failed in this orbit have not only caused serious economic losses,but also occupied precious orbital resources.For this strategic resource,the research on on-orbit service technology for satellite maintenance,life extension and orbital garbage removal is of great significance,and spacecraft close-range relative navigation technology is a key link.In recent years,research results in computer vision have been successfully applied in the industrial and commercial fields,improving human productivity and quality of life.However,due to the high risk,high cost and high reliability of space exploration,on the one hand,it is impossible to provide the equivalent of ground power and equipment support in the orbit,so that the theory and method of image processing and computer vision are in the field of spacecraft navigation and positioning.There is a big gap between the applications;on the other hand,at close range,visual navigation is the only relative navigation method.The subject is to study some key problems of the relative pose measurement of the ring target on the spacecraft.According to the practical application background,a complete and feasible visual relative measurement scheme is proposed and implemented to meet the relative pose measurement method of the ring target.Requirements for real-time,accuracy and stability.The subject divides the relative pose measurement of the ring target into two phases,which are based on the ring target edge point measurement method and the ring object based square point detection method to detect the known size of the ring target pose.The research content of the subject includes:1.In the long-distance phase,complete ring target imaging can be observed,and the first position and tracking are used to detect the pose.For the first frame ring target imaging detection,the stability of the Hough circle and four-point co-circle constraint method is discussed.For the tracking method,the real-time performance of template matching and scribing edge gradient method is discussed.For the edge point detection method,the discussion is discussed.The accuracy of the pixel-level and Gaussian-based sub-pixel detection method;for the pose-based method based on the ring target edge point,the real-time performance of the single circle based position calculation and ring modeling detection method is discussed.2.In the short-distance phase,since the complete ring target imaging cannot be completely observed,the measurement method in the long-distance phase is not feasible,and the detection method of the 3-D Points is proposed.For the detection of square target points,the applicability based on the marker detection method and the linear structure based light detection method is discussed.For the pose calculation method based on the 3-D Points,the multi-point fit space circle is used for calculation.In addition,the paper proposes a simple and easy linear structure cursor setting method for 3-D Points detection based on linear structured light.In order to verify the feasibility of the proposed scheme,several sets of semiphysical simulation experiments were designed and completed,which verified that the proposed scheme satisfies the real-time,accuracy and stability of the relative pose measurement of the ring target.Several methods for the study of relative pose measurement of ring targets are an exploration of image processing and computer vision in the field of aerospace engineering applications.The theoretical methods,data resources,lessons learned and test results in the research process will form the technical accumulation of China's onorbit service tasks.