Time-shortest trajectory optimization for hypersonic vehicle

By Pontriaghin Maximum Principle, necessary condition and boundary condition of optimal trajectory were obtained. Two point boundary value problem (TPBVP) was solved by means of the genetic algorithm (GA) and neighboring extrem method (NEM). The scope of initial adjoint variables was estimated by the scope of the attack angle obtained by suboptimal trajectory. The goal optimal value was obtained by GA in the scope. The boundary value condition and constraints can be satisfied by NEM. By a hypersonic numerical application, the control law of the angle of attack and time-shortest trajectory was gained. Compared with suboptimal flight scheme, the flight time obtained by optimal control method is shorter than that by suboptimal method.