Robust Optimal Control of Low-Thrust Interplanetary Transfers

Continuous-thrust orbit transfers are designed by solving an optimal control problem that minimizes fuel consumption while satisfying mission constraints. The optimal control problem is usually solved in nominal conditions: at the design stage, the dynamics modeling is supposed to exactly represent the reality. An algorithm to include uncertain parameters and boundary conditions is presented. This is based on the high-order expansion of the solution of the two-point boundary value problem associated to the optimal control problem with respect to uncertainties. Illustrative applications are presented in the frame of the optimal low-thrust transfer to asteroid 1996 FG3.