The RemoveDebris mission was an EU-funded project aimed at demonstrating key technologies for active debris removal (ADR) in space. While not a full end-to-end ADR demonstration, RemoveDebris tested critical components needed for future debris removal missions.
Overview
The RemoveDebris spacecraft was based on a 100kg satellite platform developed by SSTL called the SSTL-50. It was equipped with several payloads to demonstrate debris removal techniques:
- A net to capture a target CubeSat
- A harpoon to spear another target CubeSat
- Vision-based navigation using cameras and LiDAR to track targets
- A drag sail to quickly deorbit itself after the experiments were complete
Two target CubeSats called DebrisSats were housed inside the main spacecraft. These were ejected and used as artificial debris to test the capture mechanisms.
The project brought together a consortium of companies and academic institutions including Airbus, SSTL, ArianeGroup, ISIS Space, CSEM, and the University of Surrey. It received funding from the European Union FP7 program.
Mission Timeline
RemoveDebris was delivered to the International Space Station (ISS) in 2018 aboard a SpaceX Dragon capsule. It was deployed into orbit from the ISS Kibo module on June 20, making it the largest satellite ever deployed from the station at that time.
Shortly after deployment, the two DebrisSats were ejected. DebrisSat-1 was designed to be captured by the net while DebrisSat-2 was the target for the harpoon.
On September 16, 2018, the net was successfully deployed and captured DebrisSat-1 at a distance of about 11 meters. This was the first demonstration in history of using a net to capture a piece of debris in space.
In February 2019, the harpoon was fired at a range of 1.5 meters and also successfully captured its target. This further demonstrated the viability of capture technologies for debris removal.
Throughout these experiments, the vision-based navigation system tracked the targets using cameras and LiDAR, proving its ability to provide relative positioning data during debris capture.
After the capture demos were complete, the drag sail on RemoveDebris was deployed in March 2019. Such sails increase the spacecraft’s surface area to quicken orbital decay. The sail performed as expected and RemoveDebris reentered Earth’s atmosphere in December 2021.
Outcomes
The RemoveDebris mission was highly successful in progressing key ADR technologies to higher readiness levels. Both the net and harpoon capture mechanisms performed well and could be scaled up for larger debris targets in the future.
The vision-based navigation also showcased the potential for cameras and sensors to provide the relative positioning and tracking data needed for debris removal operations.
Finally, the drag sail test helped mature this technology for deorbiting defunct spacecraft faster to prevent them from becoming debris.
Summary
RemoveDebris provided vital in-orbit verification for several ADR components. It brought together leading institutions to tackle the growing issue of space debris and served as an important stepping stone toward future debris remediation missions.
The mission showcased international cooperation and technology sharing needed for the monumental task of debris removal. It also highlighted techniques that could potentially help ensure the sustainable and responsible use of space for generations to come.
Reference: EO Portal
