Abstract: Aiming at the urgent requirements of the current large-scale water survey and bathymetric work, this paper designs a new towed bathymetric survey system. The system makes creative improvements to the existing single-beam bathymetry device, and designs a modular electronic warehouse and floating body, which can be quickly deployed and recovered by unmanned aerial vehicles and other equipment, and carry out bathymetry survey by towing on the surface of the water.CFD simulation analysis and field tests show that the system exhibits good resistance and stability under different water velocities, with a drag force of 53.36N for the system when the maximum water velocity is 3m/s. The internal conformity accuracy of the system for bathymetry in open water is 0.0245m, and that of the unmanned ship is 0.0342m. The experimental accuracy is in accordance with the requirements of the relevant national specifications. This system with reliable accuracy and stable operation,can be quickly deployed and recovered,and is especially suitable for measurements in waters with steep slopes where unmanned boats can not be deployed, or in waters such as densely arranged pits and ponds. The results validate the application potential of the proposed proposed system in complex waters and provide an innovative solution for bathymetric surveying.

Key words: bathymetric survey system, towing, modularization, CFD simulation, accuracy verification