Design and optimization of Earth-Mars optimal-fuel low-thrust trajectory

The design and optimization of low-thrust trajectory is the one of significant technologies for interplanetary exploration missions. We have presented a search approach for launch opportunity based on contour map, which could provided the close distance information between spacecraft and Mars. According to that, we could find the opportunities satisfied with constraints. Then, based on the search solution for launch opportunity, a direct optimization method was employed to compute the optimal-fuel low-thrust trajectory, in which, a parameter optimization problem was reformulated by discretizing the continued control variables, and the sequential quadratic programming algorithm was used to solved it. The validity of search approach for launch opportunity and optimization method is verified by numerical calculation.