Design Of Spaceborne Deployable Biaxial Pointing Mechanism For Dual-reflector Offset Antenna

Satellite Internet systems have gradually become the main trend in the development of satellite communication technology with the advantages of wide coverage,low latency,large capacity,and freedom from geographical influence,and have great commercial value and important strategic significance.The spaceborne antenna pointing mechanism is at the forefront of the satellite communication system,and its performance will directly affect the communication quality of the satellite system.The development of a high-performance,low-cost spaceborne antenna pointing mechanism has become one of the main research directions for the future development of satellite Internet systems.This article combines the actual needs of the low-orbit satellite Internet project,through a combination of optimized design analysis,dynamic simulation and experimental verification,and proposes a design scheme of light,miniaturized and wide coverage deployable biaxial pointing mechanism for spaceborne dual-reflector offset antenna.This solution effectively solves the problem that traditional X-Y and azimuth-pitch pointing mechanisms are difficult to obtain a larger range of motion while considering the volume and weight.This article antenna pointing mechanism design work is as follows:(1)Summarized and analyzed the advantages and disadvantages of various types of spaceborne antenna pointing mechanism configurations at home and abroad,and based on the characteristics of the dual reflector offset antenna and the special requirements of the aerospace system,a design proposal of light,miniaturized and wide coverage deployable biaxial pointing mechanism for spaceborne dual-reflector offset antenna is proposed.(2)Through the study of the theory of composite material classic laminates and the theory of structural size optimization,with the smallest linear expansion coefficient and the highest structural rigidity as the optimization goals,the layering optimization and the cross-sectional size optimization design of the connecting rod components are carried out.The optimized design effectively improves the thermal stability and dynamic performance of the connecting rod.(3)To avoid quality redundancy,the lock release device and structural support are integrated design based on the SMA linear two-way offset drive.By establishing a mathematical model to analyze the influencing factors of the anti-overturning moment performance of the locking support structure,the optimal configuration parameters of the locking support structure are finally obtained,which improves the light and miniaturized of the pointing mechanism.(4)Through the combination of dynamic simulation and experimental verification,the dynamic performance of the pointing mechanism is verified.Then the pointing accuracy,speed stability,and angle accuracy of the pointing mechanism was measured.The results show that the performance indicators of the pointing mechanism meet the requirements.The above design optimization and experimental testing will have important theoretical and engineering reference significance for promoting the application of dual reflector offset antennas in aerospace systems and improving the communication capabilities of our national satellite systems.