Weighing in at 8 tons at the moment of its launch and now decommissioned and following the already crowded Sunsynchronous orbit, Envisat was ESA’s last EO satellite and the first on the active space-debris removal list due to the high probability of its collision with other objects.

The ongoing phase, in which GMV is playing a key role in an Airbus-led team, focuses on implementation of the findings from the intermediate System Requirements Review (SRR) for adaptation of a GEO servicing vehicle (Spacetug concept) to the e.Deorbit mission.

Specifically, a team made up by members from GMV’s Portugal and Poland subsidiaries is responsible for adapting the guidance, navigation and control (GNC) system for the orbitalrendezvous, inspection and stackorbit phases, comprising a bespoke guidance system, a camera-based relative navigation filter and an H-infinity robust controller. The study includes the carrying out of high-fidelity, worstcase-scenario simulations to study

GNC performance in unfavorable conditions. A study will also be made of the performance of the complete camera-based navigation chain and a high-fidelity image generator will be developed, plus a vision-based navigation model to be included in the simulator.