End-of-life earth re-entry for inclined geosynchronous orbits

In this work, the Earth re-entry by exploiting the lunisolar perturbations with low-thrust maneuvers is studied for the need to investigate alternative end-of-life disposals for satellites in the inclined geosynchronous orbits. A simplified double-averaged semi-analytical propagator is built for long-term orbital propagation, which is accurate enough and much more efficient in calculation. The J2 perturbation and lunisolar perturbations are directly modeled into the low-thrust trajectory optimization model and the related analytical derivatives are derived for the shooting procedure, which is essential to guarantee the convergence of fuel-optimal problems with perturbations. By studying the parameter space of orbital lifetime, an effective fast re-entry disposal strategy is proposed. Then, a multi-revolution low-thrust maneuver design method is proposed in the perturbed environment. The feasibility of combining the proposed fast re-entry disposal strategy and the proposed low-thrust maneuver design method to achieve cost-efficient fast re-entry for satellites end-of-life disposal in the inclined geosynchronous orbits is verified in this work. This work sets up a frame to exploit the applications of low-thrust maneuvers for end-of-life disposals in the inclined geosynchronous orbital region.