Conceptual Study Of Spacecraft Replacement Unit For On-orbit Servicing

By performing on-orbit repair, upgrade, fuel adding and other operations, satellite on-orbit servicing technology can effectively reduce the cost of space missions and extend the life of satellites. Therefore, it has been implemented for a long time. In order to further reduces the servicing cost and the hazard to humans, autonomous on-orbit servicing technology which uses space robots to perform servicing behavior has been the world’s research emphasis in recent years. Modular satellite technology which references widely the modularization concept of design, manufacture and maintenance in fields of industry, can improve the speed of satellite development and reduce its cost. At the same time, modular satellite technology has great potential in reducing the difficulty of on-orbit servicing operation, so it is an important supporting technology for on-orbit servicing.This paper conducts a conceptual study focusing on key technologies of satellite replacement unit for on-orbit servicing. First, this paper analyzes and summarizes features of modular satellites and orbital replacement unit abroad, designs the overall concept modular satellite, orbital replacement unit and unit adaptor. The satellite’s overall design includes its shape, main structure and assembly sequence of modules. The design of orbital replacement unit and unit adaptor includes structure, mechanism and control circuit which can achieve the requirement of connection and release function. Secondly, this paper analyzes and summarizes features of Space Plug-and-Play Avionics and Satellite Data Model, and depending its principle of plug-and-play, develops Modular Satellite Data Model; to a certain extent, this model realizes the self-identification and self-configuration of modular avionics, then supports modular satellites’ on-orbital replacement and upgrading. Finally, this paper manufactures the principle prototype of orbital replacement unit and unit adaptor, and adjusts it to the normal working condition; develops a set of demonstration system of plug-and-play function which can monitor module’s connection state, process and display the data from the avionics and command the principle prototype to release the module; conducts simulation experiment of on-orbital module replacement in which industrial robot operates the orbital replacement unit to connect and release from the adaptor, and this experiment verify the rationality and reliability of the module and adaptor.