Improved time-optimal static programming algorithm for hypersonic vehicle

To resolve the problem that the performance index is not optimal under the free terminal time, an improved time-optimal static programming algorithm (ITOSP) is introduced for the hypersonic vehicle. In this algorithm, the optimal initial value generator (OIVG) is used to generate optimal initial values for subsequent static programming algorithm. The improved static programming (ISP) algorithm is used to produce trajectories that satisfy the constraints with Trapezoidal integral. And the improved particle swarm optimisation (IPSO) algorithm is applied to optimise the terminal time to minimise performance index. To verify the feasibility and accuracy of the proposed method, the analysis and simulation of hypersonic vehicle static programming example for the free and fixed terminal time are carried out in three-dimensional (3D) scene. Compared to the general-purpose optimal control software (GPOPS), the proposed method has good convergence accuracy of terminal states, and the accuracy of terminal errors is improved significantly.