关键词: 飞行器控制与导航技术, 小天体探测, 发射机会搜索, 遗传算法

Abstract: In the light of the drawbacks of the conventional porkchop plots method that needs a lot of computation time with low computation efficiency, a search approach for optimal launch window for exploring small celestial body was proposed based on the genetic algorithm. The approach selects the total velocity increment for the exploration mission as the objective function and the genetic algorithm as optimization algorithm. Through calculating the ephemeris and solving the Gauss problems, the complicated multivariable nonlinear optimization problem was reduced to a doublevariable optimization problem. Thereby, the coding work load and search space decreases greatly. The approach has not only the global search function, but also the good convergence property, and improves the computation efficiency. Finally, taking the 4660 Nereus asteroid as an example, searching the optimal launch window for the rendezvous missions using the twoimpulse transfer in the range of 2008－2012 years was preformed. The results of simulation indicate that the proposed approach is consistent with the conventional one, but the computation time is only the 4.19% of the conventional method.

Key words: aerocraft control and navigation technology, small celestial body exploration, launch window search, genetic algorithm