Alternative to invasive marine tracking

1 min read

A hybrid, wireless communication system for non-invasive monitoring of physical parameters of the sea and activity level of various sea animals has been developed by the King Abdullah University of Science and Technology (KAUST).

Previously, there have been no alternative to heavy and sometimes invasive tags when tracking animals in the sea.

The underwater sensing system consists of a lightweight, flexible, Bluetooth-enabled tag that stores data when the sea animal is under water. As soon as the sea animal rises to the surface, the tag automatically syncs the stored data to floating receivers on the surface.

Data is wirelessly transmitted to floating receivers, which have built in Bluetooth and GSM capabilities. Sensor data is then relayed to the GSM network to be viewed from anywhere in the world. Where there is no GSM connection, drones scan the area and pick up the signal from floating beacons.

The team is looking to develop magnetic sensors for future integration, as well as flexible temperature, salinity and pressure sensors.

According to the team, one of the biggest challenges in designing this wireless tag was to ensure good wireless communication irrespective of the tag's orientation, as the animal position, on which the tag is mounted, is unpredictable.

"You want to get radiation all around and you need a vertical element for that. We couldn't have a vertical element so the design had to be completely flat, yet perform like a three-dimensional model," Associate Professor Atif Shamin of KAUST said.

The team claim they were able to create a special flexible antenna that achieved near isotropic radiation pattern while maintaining a flat profile. The tag also needed to retain performance while maintaining flexibility and exposure to harsh sea conditions. The final challenge, according to the team, was attaching the integrated circuit – which is typically soldered on – to the flexible tag. The lightweight materials mean that heat is not an option, which led the team to explore specialised epoxies.

"The plan for this year is to integrate ultrasonic. When we do this, it will be the first ultrasonic, GSM and Bluetooth connectivity in tagged animals," Assoc Prof Shamim explained.

With ultrasonic connectivity, the researchers explained they will have access to real-time data and won’t need to wait for the animal to surface to read it.