A satellite bus, satellite platform or service module is referred to the supply unit of a satellite or a space probe, which enables the operation of the actual payload (in analogy to the spacecraft ). Here, the satellite bus remains largely the same and it is only adjusted to the appropriate payload, so that the development costs are reduced accordingly. Especially they are often used for communications satellites, whereas research satellites are rather special designs.
A satellite bus consists first of the basic mechanical structure as a support for the various subsystems. This is fixed in the development first and largely determines the subsequent configuration of the satellite bus and thus the building on the bus satellites. It refers to the static and dynamic loads during start and operation of the satellite and is responsible for its thermales behavior for the vibration and resonance behavior of the satellite bus and in broad terms. Then the subsystems are integrated in the primary structure, such as energy supply (solar cells, batteries ), the temperature control system, the drive system for the attitude and position control ( web control ) and the on-board computer system for control and data management. For manned satellites nor is added the life support system.
Technical data of different platforms
The best-known provider for satellite platforms are Boeing, Space Systems / Loral, Thales Alenia Space and EADS Astrium. They differ except in size, performance and price, especially with regard to their life and their orientations on specific tasks.