Low-thrust trajectory optimization for multiple target bodies tour mission

Spacecraft science missions to planets or asteroids have historically visited only one or several celestial bodies per mission. The research goal of this paper is to create a trajectory design algorithm that generates trajectory allowing a spacecraft to visit a significant number of asteroids during a single mission. For the problem of global trajectory optimization, even with recent advances in low-thrust trajectory optimization, a full enumeration of this problem is not possible. This work presents an algorithm to traverse the searching space in a practical fashion and generate solutions. The flight sequence is determined in ballistic scenario, and a differential evolution method is used with constructing a three-impulse transfer problem, then the local optimization is implemented with low-thrust propulsion on the basis of the solutions of impulsive trajectories. The proposed method enables trajectory design for multiple asteroids tour by using available low thrust propulsion technology within fuel and time duration constraints. (C) 2011 The Chinese Society of Theoretical and Applied Mechanics.