LOW-THRUST ORBIT TRANSFER OPTIMIZATION USING UNSCENTED KALMAN FILTER PARAMETER ESTIMATION

It is considered optimization of low-thrust transfer from a low and eccentric initial orbit toward a high geostationary orbit. The optimal control problem is reduced to the two-point boundary value problem (TPBVP) by means of Pontryagin Maximum Principle. Unscented Kalman filter (UKF) parameter estimation algorithms are applied in solving TPBVP. The algorithms are simple, efficient and robust to overcome the difficulties of guessing the initial values of the costate variables. Environmental constraints such as Earth oblateness and shadow effect are included in both minimum-time and fuel-saving cases. Several numerical simulations are presented to demonstrate the effectiveness of those proposed methods.