Abstract
Optimal trajectory design for reentry flight is studied by using Dynamic Programming (DP) method. DP is selected to make use of its ability of generating the optimal trajectory in real time as well as its simplicity to handle inequality constraint conditions for the trajectory optimization. The large amount of calculations to reduce discretization error in case of fewer control variables than the state variables is one of the drawbacks, but it is solved with two proposed techniques of Augmented Control Variables (ACV) method and the Least-error Grid-point Selection (LGS) method.
