Optimal two-body satellite path control actuated by Coulomb forces in the Earth-Moon system

This research is focused on the design of an optimal path control strategy for the two-body satellite system, which is actuated by the inter-satellite Coulomb forces, near the libration points of the Earth-Moon system. The Coulomb force is generated by electrostatically charging the satellite to different potentials, which is nearly propellant-less and eliminates the plume contamination. Therefore, it provides an attractive control actuation alternative for satellite formation flight. However, the inherent high nonlinearity and coupling of Coulomb forces make the problems considerably more complex than the traditional satellite formation. After the nonlinear dynamic model is derived by utilizing analytical mechanics theory, the method of direct collocation is utilized to solve the trajectories optimization problems. This approach converts the original problem to a finite-dimensional nonlinear programming problem with a finite set of variables. Compared with the classical perturbation techniques, the proposed method is robust, generating a control history and a nearby solution with little information required for an initial guess. Numerical simulation results are presented to validate the feasibility of the proposed optimal path control strategy.