Underwater GeometerThe detection accuracy and range vary depending on the technology type, equipment configuration, and usage scenario. Typical accuracy can reach sub meter to centimeter levels, and the detection range ranges from tens of meters to thousands of meters.
1、 Detection accuracy: spanning from sub meter to centimeter level
Multi beam depth measurement system
Sub meter level accuracy: Conventional equipment can achieve sub meter level (<1 meter) detection accuracy, suitable for scenarios such as waterway surveying and port construction.
Side scan sonar technology
High resolution imaging: Side scan sonar generates seabed topography images through sound wave backscatter signals, and the resolution is related to pulse width and horizontal beam opening angle.
Typical parameters:
EdgeTech 4125: Detection accuracy of 2.3-0.6 centimeters, suitable for high-precision terrain mapping in shallow water areas.
GeoSwathPlus: Coherent side scan sonar with a detection accuracy of 2.4-0.6 centimeters. It accurately locates the detection point through the phase of the acoustic echo, improving the accuracy of strip detection.
Synthetic Aperture Sonar (SAS)
Centimeter level resolution: The new SAS technology improves the resolution to centimeter level and can detect cables with a diameter of 5 centimeters at a distance of 150 meters, suitable for underwater archaeology, pipeline inspection and other scenarios.
2、 Detection range: coverage from tens of meters to several kilometers
Short distance handheld devices
SV1005 Underwater Landscape Scanner: Handheld operation, with a maximum detection distance of 40 meters, suitable for divers or small boats to finely scan specific areas such as reefs, fish nests, and sand pits.
Underwater terrain search and rescue sonar detector: supports a maximum scanning range of 100 meters, with a streamlined three wing probe structure to enhance towing stability, suitable for emergency rescue, public security, maritime and other fields.
Medium to long distance shipborne equipment
Multi beam depth measurement system:
Shallow water area: When the operating speed is 5 meters per second, the effective coverage width of the strip is 7.5 times the water depth (such as covering 750 meters when the water depth is 100 meters).
Deepwater area: Covering a width of up to 4000 meters at a depth of 5000 meters, suitable for deep-sea geological surveys.
Side scan sonar:
Ship borne: Wide detection range, high efficiency, but low resolution, suitable for rapid mapping of large terrain areas.
Dragging type: The height of the towing body from the bottom of the water can be adjusted according to the task requirements to obtain high-precision data, but the detection efficiency is limited by the speed (usually ≤ 5 knots).
Ultra long distance sonar
Low frequency sound wave technology: using low-frequency sound waves below 10 kHz, with a range of up to tens of kilometers, suitable for deep-sea surveys and remote target detection.
3、 Technological breakthroughs and scene adaptation
Environment adaptive algorithm
Dynamic beam control: The device is equipped with a built-in pressure sensor and gyroscope, which can monitor the water flow velocity (0-5 meters/second), water temperature fluctuations (± 10 ℃), and ship attitude changes (± 15 ° tilt) in real time, and automatically adjust the sound wave emission angle and pulse width.
Case: In the monitoring of Xiaolangdi Reservoir on the Yellow River, the system maintained a water depth measurement accuracy of ± 0.02 meters in the face of a flow rate of 3 meters per second and waves of 0.5 meters per second, reducing the error by 80% compared to fixed parameter equipment.
Multi band acoustic detection
Dual frequency transducer: If the intelligent depth gauge adopts a 200kHz/400kHz dual frequency design, the high-frequency band (400kHz) penetrates the sediment layer in a shallow water area of 0.5 meters, and the low-frequency band (200kHz) penetrates the turbid water body in a deep water area of 30 meters, synchronously obtaining the characteristics of the sediment interface and riverbed topography.
Application scenario: In the Yangtze River estuary waterway regulation project, this technology successfully identified a 0.3-meter-thick siltation layer and a 1.2-meter-deep scour pit, providing accurate data support for dredging construction.
Anti interference and corrosion-resistant design
High turbidity water body: For the Yellow River Basin with sediment content exceeding 10kg/m ³, a "high-frequency sound wave+anti-interference probe" is used, which has strong sound wave penetration and avoids the influence of sediment adhesion on measurement.
Highly corrosive environment: The equipment casing is made of 316L stainless steel and polytetrafluoroethylene composite material, with a protection level of IP68, which can resist the erosion of seawater salt spray and acid-base solutions. A coastal port equipment has been running continuously for 3 years without corrosion in an environment with a salt spray concentration of 80mg/m ³.