Reentry trajectory optimization of hypersonic vehicle based on pseudo energy

The whole heating of the hypersonic vehicle in reentry process was minimized based on the pseudo energy, which is used to divide the reentry trajectory into some segments. The control variable parameterization with different time durations was introduced to optimize each trajectory. The reentry trajectory of the hypersonic vehicle must satisfy the heating rate, dynamic pressure and the overload path constraints. The control variable parameterization was applied and the trajectory optimization problem become a nonlinear programming problem by the time scaling and the inequality constraint transformation. The pseudo energy definition was introduced to divide the reentry trajectory into some segments for optimization. A case with four segments was taken as an example for simulation. The computing time is less than that of one segment by 50%.