Mars atmospheric entry trajectory optimization with maximum parachute deployment altitude using adaptive mesh refinement

摘要

In this paper, we present an adaptive mesh refinement method that is used in conjunction with local direct collocation methods for solving Mars entry trajectory optimization problems with a maximum parachute deployment altitude. The study focuses on the capability of the mesh refinement method to solve Mars entry trajectory optimization problems and the potential benefits of enabling angle-of-attack control. The numerical results show that Mars entry trajectory optimization problems can be solved accurately and efficiently using the proposed method. The accuracy is found to be comparable to that of indirect methods, and the computational time is on the order of several seconds, depending on the complexity of the problem. Furthermore, it is found that parachute deployment altitude gains of 2.2-3.1 km over pure bank control are possible if angle-of-attack control is enabled for a Mars Science Laboratory-type vehicle. Efforts are also made to investigate the influences of bank angle limits on entry trajectories, and it is found that the structure of the optimal bank angle profiles are generally similar for different bank angle limits, but a larger bank angle range allows an higher maximum parachute deployment altitude.