Surveying the Majestic Skarnsund Bridge Using the WINGHEAD i80S Multibeam Echosounder

A Small boat of opportunity was used for the mobilization. Without making any physical modifications to the boat gunwale, we chose to mobilize using 2”x4” timber, ratchet straps and the carbon fibre “PORTUS” Pole mounting Pole. A truly expeditionary installation.

The WINGHEAD i80S multibeam sonar – despite being a market leading on numerous parameters including size, weight, resolution and features – installs using only a single cable. Very convenient for repeated installations on boat of opportunity.

The small NORBIT iLiDAR was also mobilized. The iLiDAR is installed on a dedicated bracket on the PORTUS Pole – and it interfaces to the same NORBIT topside as the sonar, also using only a single cable.

With the easy-to-assemble and -install PORTUS Pole all lever arms are known – and therefore we were able to mobilize and collect the first data in less than an hour. Literally.

GNSS RTK corrections were interfaced to the system in real time, using the NORBIT GUI-integrated NTRIP client.

Data was logged using the integrated logging feature in the NORBIT GUI. Survey progress was monitored and controlled from an iPad using NORBIT DCT – our NORBIT data acquisition software. NORBIT DCT provides a great and easy-to-understand survey overview in a standard internet browser, to any device on the boat network – or via VPN to ground staff in the office.

Survey

The task was to survey a high-current area around the Skarnsund Bridge located in Norway at nearly latitude 64°N. Approximately 1,000,000m² was covered with high density data in about four hours of survey. For increased and even data density – especially in the deep areas – we made use of two unique valuable features. Active Pitch Stabilisation and Dual Swath.

Dual Swath produces two simultaneous pings, each providing 1024 discrete beams – resulting in total of 2048 beams per Dual Swath-ping. In other words, we achieve a data density that would otherwise require two sonars to obtain.

Pitch Stabilisation actively compensates for the pitch motion of the vessel – providing improved uniformity of the sounding on the seafloor. This means that data distribution is now much more predictable, since vessels pitch motion is being actively addressed directly by the sonar.

The combination of Dual Swath and Pitch Stabilisation provides a very dense and very even data distribution.
This allows for more efficient survey planning and for faster completion of the survey.

Water depth ranged from less than 30m up to +200m.
Despite the water depth, the WINGHEAD i80S was efficient at 400kHz throughout the area.

Yaw Stabilisation

The WINGEHEAD i80S also offers active yaw stabilisation. When a survey vessel yaws around the pre-planned survey line, the data density on the outer beams suffer. The yaw stabilisation feature of the WINGHEAD i80S dynamically and actively compensates for this, thus ensuring a significantly more even and predictable point distribution. This allows for more efficient survey planning and faster completion of survey tasks.

Fully stabilised – fully integrated – small form factor – low power

The WINGHEAD i80S is truly unique with its:

• tightly integrated INS
• roll stabilisation
• active pitch stabilisation
• active yaw stabilisation and
• dual swath

All features have been designed to help our customers to achieve their survey goals faster and more cost effective. Despite the long range of advanced features, the WINGHEAD i80S continue to follow the NORBIT concept of having just a single cable connection to a minimal topside. Combined with low power consumption and low weight, the WINGHEAD i80S is – with margin – the most powerful small form factor solution in the market.