ESA GNC Conference Papers Repository
NEOShield Project: GNC Design and Performance of an Asteroid Kinetic Impactor
The NEOShield project has been set and funded by the European Commission (FP7 program) to investigate different mitigation techniques aiming at cancelling out the impact probability with a threatening Near Earth Object (NEO). Among the different possible techniques (underground or surface nuclear blast, gravity tractor, etc.), the kinetic impactor seems very promising for several reasons: the lower complexity level of the mission compared for instance to the complex proximity operations of a gravity tractor, its links with the developed technologies within Airbus Defence and Space, and its suitability for the deflection of rather large objects with limited warning time. Within the frame of the NEOShield consortium, AIRBUS Defence and Space has been retained to investigate the GNC design and solutions for a kinetic impactor relying on satellite-like or kill vehicle-like propulsive designs, these concepts being investigated at different levels by GNC teams from Toulouse and Les Mureaux. This paper presents the GNC design and performance for impactor definition relying on very low (10 to 20 N satellite-based propulsion) to medium (200 N to 400 N ATV-based divert) or large (3500 N HOMER-based divert) liquid-fuelled divert system. The main features of the GNC chain including the timeline definition of the endgame phase and sensor choice are first pre-sized and traded-off using dedicated sizing techniques inherited from Airbus DS in house experience. Then, a focus is made on the different concepts with the presentation of the retained Guidance, Navigation and Control techniques, including details on Image processing used in the navigation, and the performance of the GNC solutions is eventually established using 6 DOF Monte-Carlo simulations with or without the image processing in the loop considering relevant mission hypotheses. The research leading to these results has received funding from the European Commissions Seventh Framework Programme ([FP7/2007-2013]) under grant agreement #282703.