NSGA-III Based Trajectory Optimization for Landing in Planetary Pits

Exploring the moon has always been a popular topic among researchers. With the discovery of pits on the moon, researchers have another different option to further explore the moon. But landing in the lunar pits will be much more difficult than landing on the moon's surface. To solve this problem, the paper proposes an NSGA-III based spacecraft trajectory optimization method for landing in planetary pits based on the discretization of the original problem. Firstly, according to the discretization model of the original problem, the chromosome of each individual is initialized into a fixed-length thrust sequence, so that we can then apply a randomly generated thrust sequence to calculate the path of each individual. Then, an NSGA-III based spacecraft landing trajectory optimization method is proposed to optimize the fuel consumption and the landing speed by improving the thrust provided by the engine along the landing path. In addition, the CV-first non-dominated sorting method is adopted to ensure the feasibility of the solution obtained by the method. Finally, the simulation of the proposed method is performed and the results show its efficiency and feasibility in solving pit landing trajectory optimization problems.