Simulation and optimization of spacecraft re-entry Trajectories

Abstract

Parameter optimal control has the advantage of often being easier and faster to solve than general optimal control methods, and may be better suited to the task of spacecraft re-entry trajectory optimization. In this thesis, a parameter optimal control algorithm is implemented in MATLAB® to optimize a 2-D re-entry trajectory simulated via Simulink®. Simulation results are validated by comparison with data from the flight of Apollo 4. Behavior of the algorithm is observed as it optimizes the control input under different conditions without constraints applied. The performance of the optimization program is observed as the complexity of the control input is increased up to the point where constraints are required to continue the optimization process. Finally, a guide is laid out for further development of the algorithm towards both pre-flight trajectory planning and real-time control applications for re-entry.