PrefaceAlong with the development of society, GIS data plays important role in economic operation. It was said that GIS data is the cornerstone of digital China. At present, GIS data on land is quite abundant, while underwater terrain data is much less. In some area, it is even blank. So the underwater bathymetry technology and application get more and more attention. Today, we will introduced a small size, high accuracy and low power consumpation multibeam echo sounder suitable for unmanned surface vehicle, which could survey the area that manned hygrographic ship can not reach, especially shallow water area.In the traditional knowledge of surveyors, underwater terrain surveying and mapping work is down on big hydrographic ship equipped with multibeam echo sounder cruising on large rivers or oceans. Therefore, only where is a ship or boat, there is a way to obtain underwater geographic information data. However, there are still a lot of unpopulated area in the country that are full of water area, but lack of ship.You may   ask what is the current status of the of unmanned surveying ship development? As the sharp tool of bathymetry, what is the development status of unmanned surveying ships configuration and equipment?At present, there…

Application BackgroundPrevent and control water pollution is an important part of ecological environment protection. Water environment monitoring and pollution source tracing is the basic measure. In the past, it was very difficult to realize this purpose via manual methods to accurately prevent pollution.Pollution source tracing is the pain spot of the industry too. Nowadays, technology had developed and there are many advanced equipment being used to detect water pollution sources. They include   underwater optical camera, underwater imaging sonar, side scan sonar, water quality sampling (by analyzing water temperature, pH value, dissolved oxygen, turbidity, COD), etc. Location：River in some Industry ZoneEnvironment：Quite complicated. Water qulity is bad and smell pungent stinky. First of all, the locan Environment Protection Department is urgent to find out the polution source, then they can make out resoving method. So that they are able to realize the sustainable development of ecological environment. Difficulties：1）Surveying the whole 9km river, 6km of which is along the Industry Zone area. The current is very slow. Most of the river bank is hard and some is soft. River is narrow and two side is shallow full of seaweed. It is not convenient to dirve traditional motor boat. So unmanned surface vehicle is a good…

1 Project Requirements In May 2021, we participated in a project of "Offshore Wind Power Operation and Maintenance Pile Foundation Scouring Detection" in the sea near Lianyungang City. The task had planned to use the multibeam echo sounder to examine the scouring and silting situation within 100m around the pile foundation of 48 wind turbine in order to screen and investigate the complete hidden dangers of the underwater part.   The wind farm consists of 48 wind turbines scattering as nearly square area as shown in following fiture, which is 6500m width from north to South and 8000m length from east to west. It is gradually deepen from southwest to northeast. The water depth in shallow area is about 3m and it can reach 12m in deep water. Wind Turbine Distribution Diagram   There are 4 difficulties in surveying area investigation and assessment.   1、Flow speed is very quick The wind farm is located on the North Bank of Guanhe River entance to the sea. There are several rivers of Xinyi River, Guanhe River and Wuguan River intersecting flow into the sea at this place. The water flow situation is relatively complex here. The flowing velocity is quick and the…