| Project Detail |
Space industry is growing at an unprecedented rate with more satellites launched into low Earth orbits (LEO) each year than ever before. This is leading to an increasing number of collisions of uncontrolled space objects and space debris accumulation in LEO. Sustainability of the space economy requires new techniques to address space debris. REDECORATE proposes CubeSat swarms as a cost-effective way to mitigate space debris. It develops a debris deorbiting and recommission concept combining novel control and guidance approaches and a CubeSat swarm equipped with staged ionic electro spray engines (iESE). A CubeSat swarm can rendezvous with space debris, dissipate its rotational energy (detumble) using reaction wheels. The main thrusters lower the debris orbit to burn-up the system in the atmosphere. Such a mission is highly challenging, requires coordinated CubeSat swarm guidance and control, reliable hardware and effective propulsion - a combination which does not exist so far. First, staged iESE thrusters facilitate longer missions and achieve higher reliability and thrust than standard CubeSat propulsion. If the CubeSats are attached around a decommissioned satellite, coordinated activation of the iESEs can function as a new control system for detumbling (avoiding unreliable reaction wheels), deorbiting and due to their long life-time even recommissioning. Second, a safe-by-design hierarchical control framework will be developed to address the need for high reliability. It uses a planner-tracker feedback stack and addresses all mission segments. Third, integral quadratic constraints (IQCs) will be used to increase robustness w.r.t. system uncertainties and communication delay inside the swarm. The feasibility of the concept will be validated using IQC-based and probabilistic robustness analyses on a digital twin of the iESE CubeSat swarm and microcontrollers-in-the-loop. In summary, the project will provide Europe with know-how to tackle the space debris crisis. |
