Upgrading and experimentation of the hydraulic-driven in-situ sediment acoustic measurement system

The self-contained hydraulic-driven in-situ sediment acoustic measurement system (HISAMS), developed in 2009, was upgraded with improvement of the real-time image and data collection functionality in Oct 2015. An underwater camera and some sensors are supplemented, and a new visualization and control electric unit was integrated into the updated HISAMS, which could monitor the underwater working status of the system and transmit the image and data into the onboard control panel via the coaxial cable or optoelectric composite cable. Furthermore, the maximum operating water depth of the transducer was upgraded to 3000 m by utilizing new pressure-equilibrium architecture in the system. A special field experiment was conducted to test and evaluate the upgraded system in Jiaozhou Bay, off Qingdao. This system was proven to be extensively adaptable to different sediment types and research vessel condition, and useful for in-situ determination of the sound speed and attenuation of seafloor sediment.