Intelligent sliding-mode guidance for hypersonic vehicle in dive phase with multiple constraints

An intelligent sliding-mode guidance strategy which can satisfy terminal impact point and falling angle constraints is presented to resolve the guidance problem for hypersonic vehicle in dive phase. It constructs the relative motion equations in diving-plane and turning-plane, and studies sliding-mode guidance laws with the aid of sliding-mode control in the two designed planes, respectively. Besides, it proves the Lyapunov stability and analyzes bound of guidance parameters to ensure the guidance accuracy. By employing an intelligent method based on relative distance, the controller can adjust the coefficients in the guidance laws to impair the oscillation of control variables. The results of CAV-H vehicle test show that the algorithm can satisfy terminal multiple constraints even if the outside disturbances exist, and there was no dithering in the guidance process. Therefore, the guidance strategy researched in this paper and can offer reference for high precision and strong robustness guidance of hypersonic vehicle in dive phase.