WASSP – Seabed Profiling Made Easy

Multibeam and sidescan sonar technology is actively used by hydrographers and marine scientists to generate navigation charts and study the marine environment.

Traditionally this technology has been very bulky, with large transducers requiring special hull mounts or needing to be towed, like side-scan sonar.

New Zealand marine electronics company Electronic Navigation Ltd (ENL) has addressed the shortcomings of traditional multi-beam sonar with WASSP, developing a cost-effective, easy to install, simple to use seafloor profiling system suitable for a wide range of applications in water up to 200 metres deep.

WASSP stands for Wide Angle Seafloor Sonar Profiler, a unique, versatile and powerful electronic fishing, marine surveying and scientific research tool developed, manufactured and marketed by ENL.

A Wassp WMB-160F system comprises three modules: a transducer (incorporating separate transmit and receive arrays), a signal processing box (called a BTxR) and a standard Windows XP display PC (or laptop for portable applications). The Wassp operating software runs on the display PC and manages all functions of the multibeam sonar, including display functions, storage of information and output of this information to third-party plotting systems. For full details see “Specification”.

WASSP broadens the application of multi-beam sonar and side scan technologies with specially designed, innovative, high-performance sonar arrays that are compact enough to easily mount on vessels of all sizes.

WASSP WMB-160F is a real time 3D seafloor profiler, which is also able to display 2D bathymetric contour maps, function as a conventional echosounder, a side-scan sonar and as a triple-beam sonar with variable beam width. It can display up to four different views at once.

WASSP WMB-160F’s multibeam sonar maps a 120° swath of the seafloor and water column either side of the boat, using 112 dynamic beams for unmatched detail and richness of information about the undersea environment.

Versatility plus

WASSP WMB-160F enables users to:

1. Generate detailed seafloor profiles
2. See this information in 2D
3. View shipwrecks, underwater rocks, reefs and points of interest in 3D
4. Profile areas using Side-scan
5. View seafloor hardness changes
6. Track fish schools port and starboard of the vessel
7. Overlay fish schools geographically onto a seafloor profile
8. Export this information to chart-plotting software
9. Save the raw data for later replay

Integration

Wassp multi-beam sonar receives a number of inputs to improve its performance. The data includes:

• GPS or GPS-compass information;
• Display roll stabilisation through the NMEA interface of a GPS-gyrocompass, which will provide WMB-160F with both heading and roll information;
• Built-in worldwide tide database. The software will calculate the nearest tide station and adjust the depth seafloor profiles for tide correction due to lunar effects;
• Optional water temperature and sound-speed profiles.

Careful measurement of the location of the transducer, GPS sensor and roll sensor relative to the ship’s centre is required to ensure repeatable results and performance.