Application Study of a New Underwater Glider With Single Vector Hydrophone for Target Direction Finding

The underwater glider is propelled by changing the buoyance of itself and glides forwards with the help of the hydrodynamic force. It enables the people to conduct large-scale and long-term marine observation and detection with good stealthiness, thus, it plays an important role in the stereoscopic observation system of the transparent marine engineering. Integrated with a single vector hydrophone, the underwater glider platform can perform a full-space and unambiguous direction-finding of the underwater target. Moreover, the transient and strong noise interference of platforms, produced by buoyance adjustment, pitch adjustment and propeller rotation of the glider, can be avoided by controlling the working time of the acoustic system. As for the strong and intermittent electromagnetic brake interference produced by the heading regulating mechanism, its influence on the acoustic system can be reduced or even eliminated by the vibration and noise reduction technique. To verify the target detection estimation performance of the underwater glider (before and after the vibration and noise reduction processing), pre- and post-experiments are conducted in the South China Sea in May 2018 and August 2019, respectively. The results show that before the vibration and noise reduction, interfered by the intermittent electromagnetic brake noise, the farthest detection distance of the underwater glider to the experimental ship with the velocity of 10 kn is only approximately 5 km. After the optimization, the farthest detection distance of the underwater glider to the experimental ship with the velocity of 8.4 kn can reach to 7.7 km and without the influence of the intermittent noise interference of the platform.