Oceanic sensor networks that collect and transmit real-time data could transform our understanding of marine ecology and improve pollution and disaster management. A research team from King Abdullar University of Science and Technology (KAUST) are designing marine wireless sensor networks that could vastly improve existing ocean sensing equipment.
“Currently, underwater sensors use acoustic waves to communicate data,” explains Nasir Saeed, who is working on a new hybrid optical-acoustic sensor design. “However, while acoustic communication works over long distances, it can only transmit limited amounts of data with long delays. Recent research has also shown that noise created by humans in the oceans adversely affects marine life. We need to develop alternative, energy-efficient sensors that limit noise pollution while generating high-quality data.”
One option is to use light waves, but these will only travel short distances underwater before they are absorbed. Optical sensors also rely heavily on pointing and tracking mechanisms to ensure they are correctly orientated to send and receive signals. The team therefore propose a hybrid sensor capable of transmitting both acoustic and optical signals simultaneously. In this way, a data-collection buoy on the water surface can communicate with every sensor in a network spread out beneath it.
The teams propose that their sensors will require a new energy source rather than relying on short-term battery power. They envisage an energy-harvesting system that powers fuel cells using microscopic algae or piezoelectric (mechanical stress) energy.
Image credit: Abdulkadir Celik