Design And Analysis Of The Orbital Replacement Unit Of Spacecraft

With the rapid development of space science and technology, the number of on-orbit spacecrafts is increasing. The spacecrafts can’t be maintained frequently as the ground equipment because of the launching costs and space environment. So the spacecrafts appear functional failures very often in their missions. This will cause a great loss to us. However, on-orbit unit replacement technology makes use of the space manipulator’s own fault on the serviceable spacecraft to replace the failure units, upgrade the spacecrafts and add the consumables and so on. It extends the spacecrafts’ life and keeps the missions consecutive through replacing the failure components and replenishing consumables; It improves the spacecrafts’ performance through upgrading the old components and replacing the degraded battery or sun array and so on; If the components of spacecraft can be replaced and upgraded on orbit, some of the components will not be designed redundantly, so that reduces the designing, making and launching cost.On the basis of the background above and some understanding of the replacing way of orbital replacement unit and its designing criteria, this paper has designed the mechanism and structure, established3D models and did some kinematics simulation and finite element analysis. The main work done in this paper is as follows:(1) After having studied the background, concepts, working principles, missions, the ways of replacement, designing criteria and so on the mechanism designing scheme has been raised and the structure has been designed according to the scheme. At last the3D models of the structure was established by using SolidWorks software.(2) The orbital replacement unit’s docking process has been simulated by Motion software, the plugin of SolidWorks software, while setting physical contacts, motors, springs and so on. These have proved that the mechanism and structure designing are right.(3) Static analysis and model analysis have been performed on the orbital replacement unit by using MSC.Patran&MSC.Nastran.This paper studied on-orbit unit replacement technology and made out the designing scheme about mechanism and structure which has been raised. This will have some reference value to the development of space technology on-orbit service in the future.