Researchers from KAUST are working on creating a revolutionary new network of oceanic sensors. These sensors will be able to collect and transmit high-quality data in real-time across the ocean depths. Besides providing a wealth of knowledge on marine ecology, this information could help reduce pollution, improve disaster management, and provide a comprehensive way for us to better utilize ocean resources.
“Currently, underwater sensors use acoustic waves to communicate data. 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.”
Scientists have been experimenting with optical technology as a solution to this issue. Unfortunately, light waves can only travel a short distance underwater before they are absorbed. Additionally, optical sensors rely heavily on tracking mechanisms to ascertain if they are correctly oriented. Failure to properly orient devices results in an inability to send or receive signals.
Faced with these complications, scientists opted to try out a hybrid sensor. This sensor is capable of simultaneously transmitting acoustic as well as optical signals. This allows a buoy to collect data on the surface of the water, while communicating with every other sensor in the network — no matter how far down they go.
While this could work in theory, the science of marine research demands accuracy. Measurements need to be taken from precise locations in order for scientists to use the data effectively. To overcome this issue, the team of researchers used mathematical modeling. This allowed them to develop a proof-of-concept localization technique.
This method allows sensors to transmit received signal strength directly to surface buoys. When devices need to communicate over a larger distance, the sensors can rely on acoustic signals. If the sensor is within close range of another such device, however, it can send an optical signal instead of an acoustic one.
From there, multiple measurements can be gathered from each sensor by the surface buoy. Then the buoy weighs the measurements to determine the most accurate. It can give preference to whichever sensor provides the most precise data, and then calculate where the sensors are located.
This network of sensors won’t rely on short-term battery power, however. For this extensive network, researchers have proposed an energy-harvesting system. It will be able to power fuel cells thanks to microscopic algae and mechanical stress energy instead.