On our first boat trip, a DeepVision representative guided us to make the most of their side scan sonar products. Their DeepView software allows you to save the findings as a geo-referenced image, which can then be transferred to Alltab's "Valtamer Navigator for UWIS" software as an overlay.
Water temperature was 17 degrees, the visibility about 6 meters and maximum dive depth about 10m
The image shows a side scan sonar view, which was then transferred to the diver's navigation device, Alltab tablet.
Three illustrative objects were selected during the exercise and the purpose was to find out how well the objects can be found based on UWIS and navigation software guidance. To make the exercise challenging enought, it was decided to drop the divers about 100m apart from the first target. The objects were also rotated so that the distance between them was at least 80m. With such long distances, finding objects in low visibility, rolling around, would be almost impossible without the navigation system.
Below are photos of how the dive progressed. First what it looked like on the surface and then, on the second row of photos, what it looked like underwater.
It took a while for the diver get used to the navigator, and for a moment the connection was broken in positioning due to the shade caused by the divers between the buoys and the diver unit. However, the objects were found effortiessly and the positioning accuracy was even better than expected: the locations determined by the side can sonar were found within a meter of where UWIS pointed them.
Here is a view of DeepView at the end of the dive.
It shows real-time UWIS buoy and diver locations, diver routes and destinations. Divers visited the surface twice and the image shows the transitions in the water during that time too.
The exercise also tested the use of the UWIS dynamic marks by moving the target mark to the diver view during the dive. This is described in the video (link previously on this page)
Collaboration between side scan sonar products and UWIS is a powerful tool for underwater work and exploration.
The UWIS diver unit can also be mounted on top of the ROV so that it can be controlled over the sonar image. From a computer with UWIS Tracker, you can also share the location of one diver unit as NMEA code (such as external GPS sends) with other software.
UWIS thus provides a cost-effective and device-independent control system for the control of the rovs.