Flight Trajectory Design and Simulation Analysis of a High-Altitude, Long-Distance Gliding UUV

To enhance the long-distance penetration and combat capabilities of unmanned underwater vehicles (UUVs), this study proposes a high-altitude, long-distance gliding UUV that can be rapidly deployed by a penetration platform. According to the overall scheme, the overall trajectory is partitioned into five distinct stages: the flight stage of the penetration platform, the release stage, the conversion stage, the glide stage, and the water entry stage of the gliding UUV, with trajectory characteristics discussed for each operational segment. UUV conversion, after its release from the penetration platform, is accomplished by designing a piecewise quadratic trajectory inclination angle. The feasibility of the conversion stage trajectory design is validated using a RHC algorithm. The influence of different initial velocities on UUV conversion is also investigated. The glide stage employs a reverse thrust methodology to ensure water entry safety. Trajectory characteristics in the five different stages are studied, with the simulation verifying the rationality of the overall trajectory. Accordingly, the UUV achieves a total flight range of 410 km within 633.5 s, with the designed trajectory enabling smooth conversion and high-altitude glide performance. The water entry velocity of the UUV is 33.3 m/s, and the water entry angle is −72°, meeting the requirements of load shedding on UUVs. The reasonably designed trajectory of the high-altitude, long-distance gliding UUV establishes a foundation for subsequent engineering validation.