Performance Evaluation of Rendezvous Using Model Predictive Control

Abstract

A new form of Model Predictive Control (MPC) is presented. It is shown to guarantee robust, finitetime maneuver completion for an arbitrary target region. The new method is used to control spacecraft rendezvous and its performance is compared, in simulation, with both a traditional, glideslope approach and an earlier MPC formulation. The new method is shown to use less fuel than both other controllers. The development over existing MPC formulations is the ability to explicitly minimize fuel cost for a general target point, not necessarily an equilibrium. The new formulation also guarantees robust completion of the maneuver. Given an unknown but bounded disturbance, the spacecraft will still reach the target in finite time. This is demonstrated in simulation, also showing that the new formulation of MPC o#ers lower fuel use than the glideslope algorithm when unmodeled disturbances are present.