George Z.H. Zhu
Professor and Chair, Department of Mechanical Engineering,
York University
Research Interest: Dynamics and control of electrodynamic tether system for space debris removal, autonomous on-orbit service robot for space debris removal, and multifunctional materials for spacecraft structures.  

Speech Title：Revolutionizing Space Debris Removal with Spacecraft Swarm

Abstract: Autonomous robotic active debris removal is becoming more and more important. Unlike the existing approaches to capture and manuveour the unknown uncooperative debris with an advanced autonomous robotic system, we propose to use a swarm of small and simple spacecraft (i.e., CubeSats, Nanosats…) as a potential solution to the problem. Swarms bring robustness, flexibility, and cost-efficiency to the solution. The swarm architect is based on an effective behavior-based control approach that enables the decentralized capture of a tumbling rigid body by a swarm of free-flying CubeSats in orbit. Inspired by the swarm intelligence observed in aint colony and bird flock, the proposed swarm control incorporates a flocking behavior to maneuver the CubeSats in close proximity to the surfaces of the debris. Additionally, an anti-flocking behavior is employed to optimize the distribution of CubeSats, ensuring comprehensive coverage of the debris surfaces and encapsulation of the debris shape before triggering the capture. The CubeSats are equipped with a memory capacity that allows them to synchronize their capture on the macroscopic scale using only local individual observation of landmark points on the debris and communication with neighboring CubeSats. The control is entirely decentralized, and all swarm CubeSats are interchangeable, demonstrating a leaderless self-organizing multi-agent system. This approach demonstrates promising prospects for achieving coordinated swarm-based capture of unknown uncooperative tumbling debris.