Design And Optimization Of Low-thrust Transfer Trajectory For Deep Space Exploration Mission

In the21st century，Low-thrust propulsion system has become one key technology inthe field of deep space exploration. It has a lot of advantages, suce as high specificimpulse,light weight and high control accuracye.It can greatly reduce the fuelconsumption during the long-distance exploration missions. It will be one of themain development direction of the deep space transfer trajectories.Currently, manycountries and aerospace agency have completed a number of deep space explorationmissions by using low-thrust propulsion system. In this paper, the preliminary designand optimization of low-thrust trajectory are studied in depth based on the features ofthe design of deep space transfer trajectory.First, some basic theories about low-thrust trajectories design are introduced,including the ephemeris of planets and asteroids,the trajectory dynamical models andso on. Besides, some perturbation madels and low thrust propulsion system areresearched.Secondly, the initial design of the low-thrust transfer trajectory are researched deeply.Based on FFS theories, a significant method is presented. The jobs done here areprepared for the following task.Then, the indirect shooting method and evolutionary neurocontrol optimizationalgorithm are researched deeply.Based on the two algorithms,the initial trajectoriesdesigned above are optimized.After that, the advantages and disadvantages of suchoptimization algorithms are analysed.Finally, based on the methods studied in this paper, the exploration mission ofMercury is researched. First of all, the initial mission trajectory is designed.Thensome tasks will be done to optimize the initia low-thrust trajectory. After this, aoptimal trajectory will be obtained.