GUIDANCE FOR AUTONOMOUS RENDEZVOUS AND DOCKING WITH ENVISAT USING HARDWARE-IN-THE-LOOP SIMULATIONS

Abstract

In this paper a convex guidance and control algorithm is developed to enable Rendezvous and docking with the non-operational, rotating satellite Envisat. The algorithm employs the concept of model predictive control to allow for an unconstrained time until the docking has to be achieved, while still maintaining a guidance algorithm that is computationally efficient enough to be applied in realtime. Tests are performed to evaluate the performance of the MPC, with and without feedback control. These test cases are evaluated using a functional simulator. This is complemented by hardware-in-the-loop tests using the flat-floor test facility, TEAMS. Both the functional and the real-time simulations results show that the developed algorithms enable a performance with sufficient accuracy to complete the operations. It is also demonstrated that a higher accuracy and propellantefficiency is obtained when model predictive control, without feedback control, is employed.