The technology was developed by IMR for the Ocean HUB project, for monitoring the stock of spring spawning herring in Ofotfjorden. Ocean HUB was launched in September 2002. Since then particular algorithms for extracting of data have been developed, and valuable experience regarding interpretation of data is gained. Later on the unit was further developed with tilt/turn-able transducer. Typical applications where the unit has been used is: for monitoring of behaviour and avoidance of biomass related to ship and trawl, for long time deployment for monitoring of biomass in a cold water coral reef, and for environmental monitoring in conjunction with subsea activities for the petroleum industry. In most cases there are other environmental sensors installed on the platform as additional payload.
Lander with satellite and Communications buoy ready for deployment.
The transducer and the electronic housing is installed in a gimbal, keeping the transducer in a vertical position regardless of the slant angle of the seabed. A compass with tilt and roll sensors is mounted on the transducer frame, giving the exact angle and direction of the transducer beam at all times. Dedicated motors tilt and train the transducer, according to a Pre-programmed scanning sequence. The Searching Lander is set up with standard instrumentation: computer with ER60 software, motor control software, 38 and 70kHz split beam transducers using X-GPTs . The Searching Lander has good space for payload, and additional battery container, sensors and sounder frequencies can be installed.