Flexible robotic arm for space debris disposal
The number of satellites in orbit has consistently increased in recent years, and space debris is becoming a problem. Moreover, explosions due to remaining propellant and/or collisions between satellite shreds may generate much smaller remnants provoking a cascade effect. Consequently, the probability of further collisions increases, affecting the activities developed in the Earth space surroundings. A possible solution is to provide the new satellites with a de-orbiting system that may activate once the satellite arrives at its end-of-life. However, this is not an option for the satellites currently in space.
Therefore, a system that captures and disposes space debris from usable orbits to an alternative orbit could be a viable solution. The main idea of such systems is: first, rendezvous with the disposable object (target); second, engage a capture trajectory with a mechanism that can be a robotic arm.
A vital feature of this problem is the design of the GNC (Guidance Navigation and Control) unit. The GNC system must be robust against the uncertainties (the coefficients of the flexible appendages are approximately known... etc.). Overloading of the robotic arm may happen when it catches debris. Thus a flexible boom may be used to counteract this problem, increasing the complexity of the GNC system (i.e., it becomes a subactuated system).
The goal of this thesis is twofold:
- From a theoretical point of view, the aim is to develop robust observation and control methods to cope with the uncertainties and perturbations. Sliding mode and H-infinity control have proven their robustness separately when dealing with uncertain systems; thus, a combination of such techniques will be considered. The stability of the closed-loop system must be investigated.
- In terms of application, this thesis tackles the debris disposal using a robotic arm. The test scenarios will be selected to provide challenging assessment criteria to evaluate the potential of the sliding mode and H-infinity methods.
General work planning:
- review of state of the art on flexible arm disposal system
- analysis of the structural properties of the system (observability, controllability, subactuation degree, etc.)
- development of robust controllers and observers (sliding mode and H-infinity) that will be tested in an academic benchmark and in industrial simulator.
- scientific articles writing
Framework
The PhD thesis will be co-supervised with a IPN professor. Moreover, Prof. Jerome Cieslak and Prof. David Henry are specialists in H-infinity control theory and spacecraft applications (D. Henry is an expert in GNC for the European Space Agency + many satellite/spacecraft projects) from the IMS Lab (Integration: from materials to systems), University of Bordeaux, Bordeaux, Fr will be involved in the thesis project.
Candidate profile
- Ms. Eng. Or Ms. Sc. Degree in control systems, electrical, electronic, mechatronics, aerospace, etc.
- Good English level (French is not mandatory).
- Strong analytical and communications skills.
How to apply
Candidates must send a detailed CV and a motivation letter to supervisor Dra. Alejandra Ferreira de Loza dferreira@citedi.mx. The full instructions for the postgraduate call can be checked at
Starting date
August 2021
Workplace / research stays:
CITEDI Tijuana, B.C., Mx., / Lab. IMS, Universidad de Bordeaux, Fr.
Contact:
Dra. Alejandra Ferreira de Loza (dferreira@citedi.mx) https://www.researchgate.net/profile/Alejandra_Ferreira_de_Loza