Glide trajectory optimization for hypersonic vehicles via dynamic pressure control

Abstract

This paper researches the optimal glide trajectory for hypersonic vehicles, which is extremely challenging because of the strong nonlinearity of the optimization problem. Compared to conventional methods that refer to complicated optimization algorithms, a novel optimization model is developed based on a dynamic pressure profile. By analyzing the effect of the dynamic pressure on aerodynamics and flight states, path constraints are incorporated into the profile and the terminal constraints are integrated into the restriction on the terminal altitude. Therefore, no path constraints, and only one terminal constraint, exist in the optimization model. In addition, the angle-of attack (AOA) and the bank angle can be directly derived from the profile, so the mapping between the trajectory commands and the performance index is avoided. Finally, the original problem is converted to a parameter optimization problem, which is less complex and easier to solve. The trajectory is optimized by an improved particle swarm optimization (PSO) method, in which the constraint is addressed by a comparison mechanism and the search is facilitated by a mutation mechanism. Numerical simulation indicates the effectiveness of the proposed method via various scenarios and by comparison with other methods.