THE IN-ORBIT TECHNOLOGY DEMONSTRATIONS OF THE REMOVEDEBRIS MISSION

摘要

The RemoveDEBRIS project has been the first active debris removal (ADR) project to perform a successful in orbit demonstration of technologies that can be used for ADR. In particular, it has been the first project to demonstrate two capture technologies (a net and harpoon) to retrieve large pieces of space debris. The mission was performed by a micro satellite (mass of approximately 100kg) that included two 2U CubeSats deployed during the mission as targets for the Net capture and a Vision Based Navigation experiment. The craft was released from the ISS into orbit on June 20~(th) 2018. Contact was made with the craft as it passed over the groundstation in Guildford, UK and the early operations phase went according to plan. The spacecraft commissioning proceeded nominally, de-tumbling the craft to reach a coarse Nadir pointing mode. Prime and redundant RF receivers, low rate transmitters and low level command links were tested. Then, a series of AOCS manoeuvres were performed and the Supervision cameras and Lidar system were also tested. The first cubesat was released on the 16~(th) of September 2018. This cubesat included inflatable structures to better represent the scale of a large piece of debris for the net capture demonstration. The cubesat was captured by the net at approximately 1 lm from the craft with multiple cameras on-board the microsatellte observing the demonstration. The second cubesat, was ejected from the platform on October 28~(th) 2018 and its purpose was to be observed by the Lidar cameras to test hardware and algorithm capabilities. On the 8~(th) of October 2018, the harpoon experiment was performed by deploying a target at the end of a boom and firing the harpoon (which was tethered to the mothercraft) at it. The harpoon hit the target (a small Honeycomb panel typical of satellite constructions) in the centre. The final experiment - the dragsail experiment - was activated on March 4~(th) 2019. Its purpose was to accelerate the deorbiting of the