Optimal Maneuver Trajectory for Hypersonic Missiles in Dive Phase Using Inverted Flight

To determine the optimal trajectory for the dive phase of a hypersonic missile, a maneuver strategy using inverted flight is presented. The combat scene that the hypersonic missile attacks the fixed target on the ground is considered in this paper. Particularly, a maneuvering form named inverted flight is first applied to the hypersonic missiles. Afterward, an optimal trajectory is designed by minimizing the attack time with a preset terminal flight path angle, where the constraints of the angle of attack, dynamic pressure, heating transfer rate, and normal overload are taken into account. In order to solve the designed trajectory optimization problem, an improved hp-adaptive pseudospectral method with mesh size reduction is presented. The simulation results show that the proposed algorithm can significantly reduce the mesh scale with satisfactory accuracy and the trajectory obtained by the proposed algorithm is in accordance with the actual flight law. Furthermore, contrast simulation demonstrates that the inverted flight has better trajectory performance than normal flight.