Optimal trajectory design for the lunar module in ascent stage

To realize the trajectory optimization of the lunar module in ascent stage, the dynamical model of the lunar module was established and nondimensionalized to construct the optimal control-oriented model. Based on Pontryagin's minimal principle and taking the fuel consumption as the optimizing index, the optimal problem was converted into a time free two-point boundary value problem(TPBVP). Using one of initial value hypothesizing methods, combined with the forward sweep algorithm, the TPBVP was solved and the optimized trajectory was obtained. Numerical simulation was conducted. The simulation results justify the rapid convergence rate and high reliability of the proposed method.