On-Orbit Servicing system architectures for GEO and MEO constellations

Paper number

IAC-06-D1.4.04

Author

Mr. Claude Cougnet, EADS Astrium, France

Coauthor

Mr. Bernard Gerber, EADS Astrium, France

Coauthor

Mr. Gianfranco Visentin, European Space Agency (ESA)/ESTEC, The Netherlands

Year

2006

Abstract

Currently, satellites in orbit can be functionally reconfigured through automatic or ground commands, or software modifications. This on-board evolution is limited by the architecture, the redundancy approach, and the on-board resources. On-Orbit Servicing seems an attractive approach as providing the satellite with additional degree of freedom in the management of its configuration and in its mission evolution.
A lot of studies have been carried out on the on-orbit servicing and some programmes are on going, at least to verify the feasibility of key technologies enabling the servicing. 
Different types of services can be provided to the satellite, from orbit transfer to refuelling and exchange or addition of replaceable elements. Rationales for selecting services depend on the type and mission of the satellite. Thus, on-orbit servicing could be a mission need, or result from an economical approach. 
The On-Orbit Servicing of a fleet of geostationary satellites and of a MEO constellation like Galileo is currently analysed in an ESA funded study named Satellite Servicing Building Block. This paper presents preliminary results of this study led by EADS Astrium.
The first point consists in identifying the user interest and needs that means the type of on-orbit servicing that could be done, its rationale and impacts on satellite design. Thus, for instance, the on-orbit servicing could allow to maintain operational a satellite that has a high economical value, to reduce the initial investment (reduce number of equipment, size of resources through scheduled maintenance), to support a mission evolution and a technology upgrade, to extend the satellite lifetime, or to transfer it to a graveyard orbit. The economical aspects will be one of the drivers to assess the attractiveness of the servicing tasks. A review of the satellite elements that could be subject to servicing supports this assessment. 
Based on these user interests, candidate servicing system architectures are defined and assessed. They depend on the type of servicing and to which extend the satellite is designed for serviceability. They include the servicing scenario, the servicer vehicle, logistic resupply elements like specific containers if necessary, ground segment. The composite satellite-servicer vehicle configuration will be a driver for the servicer vehicle configuration. The servicer vehicle could be sized for servicing several client satellites, in order to reduce the cost of a servicing mission. It could be supported by logistic container launched periodically, or designed for a number of missions compatible with its payload capability. 
Finally, the paper will give a preliminary description of selected candidate architecture, listing the servicing tasks, the impacts on the satellite design, the servicer vehicle mission scenario and configuration and the composite configuration. 

Abstract document

IAC-06-D1.4.04.pdf

Manuscript document

IAC-06-D1.4.04.pdf (🔒 authorized access only).

To get the manuscript, please contact IAF Secretariat.