Astroscale’s End-of-Life Services demonstration (ELSA-d) announced that it has proven the ‘core technologies capability’ required for on-orbit satellite servicing. ELSA-d was designed to help deal with the issue of space debris removal from low earth orbit.
ELSA-d is made up of two satellites, the servicer and the client. They were launched together in Kazakhstan in March 2021. The first demonstration was completed in August 2021, in which the servicer released the client and then a manual redocking was successfully performed.
The ELSA-d mission completed on 4 May 2022, demonstrated the reality of several key technologies involved in capturing space debris. These include autonomous guidance and navigation, using closed loop control from on board sensors and handover between absolute navigation to relative navigation.
Seita Iizuka, ELSA-d Project Manager said, “Proving these capabilities gives us, and our partners, greater confidence in our debris removal service developments, and I congratulate the team on this impressive achievement.”
The mission began back on January 25th the servicer was able to maintain a 30 metre distance from the client using autonomous relative station keeping algorithms, however anomalous spacecraft conditions were detected so the ELSA-d team decided for safety reasons not proceed with a full capture attempt on this mission.
After allowing the client and servicer to drift approximately 1,700 km apart on April 7th the servicer was able to get back to just 159m from the client. This was when the hand off from GPS based absolute navigation was switched to relative navigation using on board sensors.
The client and servicer satellites have been allowed to drift apart again, while the team plan for the next stage of the mission and decide if a safe recapturing of the client using the magnetic recapturing system is viable.
Photo credit: Astroscale
