In the frame of the development of the Alphabus telecommunication platform, a system study is being carried out to explore one way of increasing the spacecraft autonomy in orbit.
The main autonomy limitation of geostationary telecommunication spacecraft using electric propulsion for their North/South station keeping (orbit inclination and eccentricity control) comes from the manoeuvre triaxiality. Indeed, the diffuse plume of electric thrusters results in forces applied on the spacecraft in the direction tangential to the orbit, which is called triaxiality. Since tangential thrust creates longitude drift, the longitude has to be controlled frequently enough so that the spacecraft remains in its longitude window. |
The key issues to be addressed in this project are:
The main benefit expected from this project is to reach a higher level of autonomy for the future high power telecommunication platform Alphabus that will directly results in cost savings in the spacecraft operations.
The system architecture is the current architecture of a telecommunication spacecraft (or a constellation of spacecraft) and its ground control segment.
The project plan consists in two phases:
The first phase of the activity has been successfully completed, showing the feasibility of a new concept using accelerometers for increased on-orbit autonomy. For Alphabus an alternative option has been chosen to achieve on-orbit autonomy, and it has therefore been decided not to pursue the activity.