Research On Laser Communication And Sighting System For Micro-nano Satellite

With the rapid development of space technology,the construction of communication network using LEO micro-nano satellite platform has become a hot spot in the future.Because of the outstanding advantages of large communication capacity,light weight,low power consumption,small size and good confidentiality,laser communication provides a new way to solve the bottleneck problems of traditional microwave communication methods in communication capacity and confidentiality,as well as the requirements of micro-nano satellites in terms of load volume,weight and power consumption.It has been highly valued by Europe,the United States,Japan and other countries and invested a lot of resources to carry out relevant research,and it is actively developing towards commercialization and practicality,and it is an inevitable trend to establish a global micro-nano satellite laser communication network.Aiming at the application background of laser communication system for leo micro-nano satellite,the laser communication tracking and pointing system is deeply studied in this paper.The main research contents are as follows: 1)Through the index analysis,the tracking and pointing system is designed in detail,including the analysis of structural form,the selection of materials and the design of shafting,and the mirror assembly is studied,and the bottom arc groove structure is adopted.The stiffness and thermal deformation of the mirror assembly are optimized and analyzed by ANSYS,which provides the basis for the parameter design of the mirror assembly.2)In the process of designing and adjusting,the problem of different axes between the optical axis of the telescopic unit and the rotation axis of the azimuth shafting is encountered,through the analysis of the problem,the coaxiality adjustment device of the rotation axis and the optical axis based on the optical wedge is studied and designed,which is based on the refraction principle of the double optical wedge,by rotating the wedge angle,the optical axis is effectively adjusted to ensure its coaxial;3)In view of the fact that there is no suitable conductive slip ring for micro-nano satellite tracking and pointing system in China,the technical research of rotary flexible conductive slip ring is carried out,firstly,the preliminary model of conductive slip ring is established.The mathematical model and mechanical model of the structure are studied and analyzed,then,and the fatigue analysis of conductive slip ring is carried out by ANSYS.Based on the multi-objective genetic algorithm,the optimization analysis of the conductive slip ring is carried out,which provides guidance for the design of the conductive slide ring.Finally,the parameters of the conductive slip ring are tested and the analysis is verified.In this paper,the problems of light and miniaturization of laser communication tracking and pointing system for micro-nano satellite are solved,such as the problem of different axes between optical axis and mechanical axis when compressing the volume of tracking and pointing system,and a double wedge adjusting device is studied and designed.The rotary flexible conductive slip ring is developed,the volume,weight,friction torque and fatigue life of the rotary flexible conductive slip ring are better than those of the existing slip ring and the mathematical model and mechanical model are analyzed.It has important theoretical value and guiding significance for the subsequent research of laser communication system for micro-nano satellite.