The unmanned vessel heads towards the intertidal zone in Zhoushan's Shengsi district. [Photo/Tide News]

A dual-hull unmanned vessel designed for nearshore surveys recently completed its first field operations in the waters off Gouqi Island in Shengsi district, Zhoushan, East China's Zhejiang province, collecting key data in the intertidal zone and enabling more efficient inspection of seabed cables.

The intertidal zone, located between the highest and lowest levels of spring tides, places daily stress on cables there, increasing the likelihood of positional shifts and making regular inspections essential. Large survey ships cannot operate in the shallow zone, and manual inspections are limited to a few monthly low-tide windows, reducing efficiency.

The unmanned vessel is equipped with a tide gauge, sub-bottom profiler, and other instruments. It works in coordination with the survey ship Zhou Dian 15, creating a synchronized model in which front-end data collection and back-end analysis proceed simultaneously. This approach reduces the impact of tidal conditions and water depth, raising daily operational efficiency by about 30 percent compared with earlier methods.