The objective of the activity is to develop the critical features on the customer telecommunication platform for ready on-orbit servicing. The activity willconsider at least aids to facilitate the servicer to approach, rendezvous and perform proximity operations(e.g. visual/thermal markers, retro-reflectors), grapple fixture(s) for capture, and a re-fuelling interface. The technologies and provisions developed shall be validated by modelling and/or testing.
Targeted Improvements:Enabling telecommunication satellites, which are prepared for on-orbit servicing in terms of technologies (e.g. Xenon refuelling) and provisions.
Description: Currently, European communication satellites are not prepared for On-Orbit Servicing (OOS). On the other hand, companies have already signed contracts with satellite operators for servicing missions. This demonstrates the interest of operators for on-orbit servicing. However, this is a complexand risky operation that may still deter some of them from taking advantage of OOS. To reduce the risk,it is necessary to provide the customer satellitewith the proper means to enable capture and servicing. In particular, most futuresatelliteswill employ electric propulsion using Xenon. The transfer of Xenon is complex given its behaviour as a function of pressure and temperature. As a first step in refuelling, the TRP study ASSIST (completed Q4 of2017) developed an interface to enable chemical propellant transfer.
This activity is intended to propose the features that need to be developed to enable telecommunication satellites to be serviced on-orbit. This activitywill be limited to modifications of the client telecom spacecraft. At least markers, grapple provision, re-fuelling interface and associated modificationsof the Chemical Propulsion System and Plasma Propulsion System to enable re-fuelling, and AOCS modifications will be considered. Heating and/orpressurising the tank of the servicer and cooling of the (tank of the) client may be needed during Xenon transfer. These features shall be integrated intwo different configurations: one targeting a single assembly allowing capture and refuelling and another dedicated to support close approach andcapture aiming at different servicing options (e.g. deorbit/graveyard).
The activity will also derive a set of configuration guidelines for the integration ofthe features onto future telecom satellites to avoid any potential issue with servicing vehicles during the rendezvousand captureoperation.