Dynamics and Control of Modular and Extended Space Structures in Cislunar Environment

Proposed future space programmes, which, among others, include a space station in lunar vicinity, pose some interesting research problems in the field of non-Keplerian dynamics. This paper investigates the orbit-attitude dynamics and the control of rotational motion of an extended space structure in cislunar environment. The paper presents a fully coupled model for orbit-attitude dynamics, which is based on a Circular Restricted Three-Body Problem formulation. The equations of motion take also into account the most relevant perturbing phenomena, such as the Solar Radiation Pressure (SRP), the fourth-body (Sun) gravity and the variation in the gravitational attraction due to the finite dimension of the large space structure. Preliminary results exploiting efficient control methods are presented. Single and dual-spin stabilisation are compared and the results are carefully analysed to highlight a control strategy that is less resource consuming. The space of orbit-attitude solutions is studied to highlight possible stable conditions that may be exploited to host the cislunar station with minimum control effort. The outcomes of the research presented in this paper are intended to highlight drivers for the lunar outpost design and station-keeping cost minimisation. Furthermore, a case study for a large space structure in selected non-Keplerian orbits around Earth-Moon collinear Lagrangian points is discussed to point out some relevant conclusions for the potential implementation of such a mission.