1. Technical background, subject and technical field The project belongs to the field of aerospace technology. The long-life and high-precision relay terminal antenna pointing mechanism is applied to my country's low-orbit spacecraft. It has the characteristics of high deployment/pointing accuracy, stable acquisition and tracking, and long operating life. It is a solution to the problem of narrow beam between low-orbit spacecraft and relay satellites. Core technology for tracking and real-time two-way data transmission. 2. Main technical innovations Since 2009, this project has focused on application requirements such as full-area and full-time mission information injection of low-and-low orbit mobile spacecraft at any time, space-based measurement and control random access, and has broken through long-life and high-precision relay The key technology of the terminal antenna pointing mechanism has achieved high-precision deployment and locking, high-precision acquisition and tracking, and long-term stable operation of the antenna mechanism in harsh space environments, and has achieved the following important results: (1) Aiming at the difficulties of high-precision stable deployment and capture and tracking of large inertia antennas, a comprehensive design method of a passive speed-stabilizing deployment mechanism with centrifugal force sensing speed and frictional damping dissipation adjustment is proposed, as well as a drive assembly process for integrating high-precision short-cup harmonic reducers. A nonlinear speed control model and algorithm for the pointing mechanism under external disturbance factors are established, and a high-precision passive deployment relay terminal antenna pointing mechanism is successfully developed. The unfolding repetition accuracy is less than 0.025& deg;, the pointing accuracy is not greater than 0.017& deg; and the stable tracking speed deviation is less than 5%;(2) Aiming at the incompatibility between precision transmission and long-life lubrication of short-cup harmonic reducers in harsh space environments such as large atomic oxygen doses and large temperature alternates, a preparation method for low-temperature deposited thin film materials was invented, and a& physical vapor-deposited Ti film with omega; phase structure and a solid lubricating film based on nano-composite/multilayer technology were developed to improve the life of the solid lubricating film 4~5 times; independently developed a solid-lubricated harmonic reducer with a transmission accuracy of less than 1& prime;, and its operating life exceeded 1& times; 107 revolutions solve the problem of long-term stable operation of the pointing institution;(3) Aiming at the difficulties in ground testing of pointing mechanisms such as difficulty in external measurement of motion speed and complex trajectory of large-range motion center of mass, a high-precision pointing mechanism performance measurement method sensed by highly integrated strapdown components is proposed, and a parallel time-frequency domain adaptive filtering method is invented., solving the technical problem of narrowband interference during multi-sensor fusion, improving the test accuracy by more than 30%, and successfully developing an integrated high-precision multivariate data performance testing device and a multi-dimensional follow-up gravity unloading device. It provides speed and position measurement and evaluation methods for large-scale motion pointing mechanisms. 3. Intellectual Property Rights and Promotion Status This project has core intellectual property rights and core technologies are independently controllable. It authorized 12 invention patents, 4 utility models, 2 registered software copyrights, and published 15 SCI papers. The overall technical level has reached the domestic leading and international advanced level. It has been directly equipped in multiple satellites such as Shijian 16 01/02, Remote Sensing 19/Remote Sensing 22/Remote Sensing 27/Remote Sensing 29, Gaofen 10 and Yunhai 1. In-orbit flight has significant social and economic benefits, and has wide application prospects.