A penalty function approach to constrained Pontryagin-based Nonlinear Model Predictive Control

Abstract

We propose a Nonlinear Model Predictive Control approach to spacecraft rendezvous in non-Keplerian Lunar orbits. The approach is based on the Pontryagin Minimum Principle and allows the accomplishment of minimum-propellant maneuvers. The relative motion between the chaser and the target is described by the nonlinear and unstable dynamics of the circular restricted three body-problem. In the proposed formulation, we design a minimum-propellant controller, which leads to a bang-bang behavior of the control signal. Under suitable assumptions, simplified dynamics is employed as prediction model, in order to reduce the complexity of the controller algorithm but, at the same time, without penalizing the controller tracking performance. The proposed approach's effectiveness is validated by a simulation example.

Earth Gravity In-Orbit Sensing: MPC Formation Control Based on a Novel Constellation Model

“…Then, the same process is iterated for all the successive sampling time steps. Examples of preliminary MPC applications to this class of missions are proposed in [16,17], while the formation flight control scenario is confronted in [18][19][20].…”