HERBI – Unmanned Survey Vessel

• Price: Price on application

HERBI stands for Hydrographic Electrical Resistivity and Bathymetry Imager and is actually a packaged technique that can be deployed from various types of vessels. The HERBI-USV, however, is an unmanned survey vessel designed specifically for conducting HERBI surveys. For a while HERBI-USV was called Platypus but trade-mark and other conflicts lead us to abandon this name.

HERBI-USV can be used in various ways:

1. Throw it in the water and tow it with a manned boat. This keeps all the electronics and sensors in one compact package with a WiFi link to a remote touchscreen. It is possible to tow with a boom on a boat that can swing to the side or back so that near banks of reservoirs the boat can travel in deeper water suitable for its draught while data is acquired right near the bank. This also eliminates a common problem where roll of the boat can alter depth of a sonar sensor. When adopting this technique beware that if the HERBI-USV is towed behind a propellor then air bubbles will affect the sonar – a bad idea – keep HERBI away from the propellor thrust cone.
2. Persons walk on each bank of a channel, each towing a ropes, joined to each other towing HERBI-USV. This is an effective way of surveying poorly maintained and cluttered irrigation channels because it keeps the equipment light and simple and easy to lift over obstacles such as roads and fences or pass through regulators.
3. A 4wd travels along one bank of a channel with maintained bank access with a boom extending out the side towing HERBI-USV with a rope.
4. HERBI-USV propulsion unit is attached and self-propels HERBI-USV. This option can be very effective especially if only sonar data is required, however, it limits the drag a streamer can apply such that only small neutral buoyancy streamers or floating streamers should be towed this way. The propulsion unit spreads HERBI-USV surface area so that it becomes more able to withstand larger waves such as in the surf zone in the ocean. The propulsion unit has been designed to quickly clip on or off HERBI-USV and to fold to pack into the same half palette box as HERBI-USV. Its big disadvantages are, compared to towing with ropes, critical systems complexity, cost, battery weight, and need to charge extra batteries.