This paper proposes the use of a disturbance-based impedance controller for the capture of satellites using a free- oating robot. The use of an impedance controller is ideal for satellite capture as they can generally be tuned such that an underdamped second order system response is achieved during contact, which ensures a safe capture. First, a disturbance observer is employed to estimate the contact forces at the end-effector during impact. This estimate then feeds back in the proposed impedance to ensure that the end-effector safely interacts with the target. Simulations are performed, and the results demonstrate that the disturbance observer can accurately estimate the force. Furthermore, the results also show that the contact force is bounded and behaves smoothly when the end-effector comes into contact with a fictitious wall, which shows that the controller can achieve stable contact with a capture point.

Additional Metadata
Persistent URL dx.doi.org/10.2514/6.2018-1329
Conference AIAA Guidance, Navigation, and Control Conference, 2018
Citation
Flores-Abad, A. (Angel), Crain, A. (Alexander), Nandayapa, M. (Manuel), Garcia-Teran, M.A. (Miguel A.), & Ulrich, S. (2018). Disturbance observer-based impedance control for a compliance capture of an object in space. In AIAA Guidance, Navigation, and Control Conference, 2018. doi:10.2514/6.2018-1329