The development and experimental study of the Ballast in situ Sediment Acoustic Measurement System

A ballast in situ sediment acoustic measurement system (BISAMS) was newly developed. The mechanical structure, the function modules, the working principles, and a sea trial will be reported in this study. The system relies on its own weight to insert transducers into seafloor sediments and can accurately measure the penetration depth using a specially designed mechanism. The system comprises an underwater position monitoring and working status judgment module and has two operation modes: self-contained measurement and real-time visualization. The designed maximum working water depth of the system is 3000 m, and the maximum measured depth of seafloor sediment is 0.8 m. The system has 1 transmitting transducers and 3 receiving transducers. The transmitting frequency band is 20–120 kHz. The in situ acoustic measurement system was tested at 15 stations in the northern South China Sea, and the repeated measurements in seawater demonstrated good working performance. Comparison with predictions from empirical equations indicated that the measured speed of sound and attenuation matched with the predicted values and that the in situ measured data were reliable.A ballast in situ sediment acoustic measurement system (BISAMS) was newly developed. The mechanical structure, the function modules, the working principles, and a sea trial will be reported in this study. The system relies on its own weight to insert transducers into seafloor sediments and can accurately measure the penetration depth using a specially designed mechanism. The system comprises an underwater position monitoring and working status judgment module and has two operation modes: self-contained measurement and real-time visualization. The designed maximum working water depth of the system is 3000 m, and the maximum measured depth of seafloor sediment is 0.8 m. The system has 1 transmitting transducers and 3 receiving transducers. The transmitting frequency band is 20–120 kHz. The in situ acoustic measurement system was tested at 15 stations in the northern South China Sea, and the repeated measurements in seawater demonstrated good working performance. Comparison with predictions from empirical eq...