Australian sonar sensor designed for shallow water

Researchers from Macquarie University and the University of Wollongong have designed and built a sonar sensor capable of operating in shallow water and coastal environments. The Smart sonar and accessible hydrography project has advanced the local manufacturing of transducers for highly sensitive sonar systems, proving Australia does not need to rely so heavily on international suppliers.

High-sensitivity sonar systems are vital for water managers, dam operators, mining sites and environmental monitoring, as they enable the mapping of riverbeds, tracking of sediment movement and surveillance of underwater vegetation such as seagrass. The new transducer shows promise for surveying flood and storm-damaged areas, and coastal environments.

The project was led by Senior Lecturer in Macquarie University’s School of Computing Dr Matthew Roberts. He contributed advanced signal processing and data analytics, enabling the sonar transducer to generate detailed maps and measurements of underwater environments in real time.

“This project proves that Australia can develop underwater sonar technology from start to finish. It’s not just about the hardware — it’s about the full capability, from ceramic design to field deployment, that allows us to build systems tailored to Australian needs,” Roberts said.

At the heart of the system is a ceramic transducer — sometimes called a ‘ceramic puck’ — which converts electrical energy into underwater sound waves. The piezoelectric ceramic material, developed by the University of Wollongong, is typically used in medical ultrasounds and has now been adapted for underwater applications.

Distinguished Professor Shujun Zhang from the University of Wollongong said the high-sensitivity transducer was built on a foundation of advanced, domestically fabricated piezoelectric ceramics, crucial for operating in complex shallow waters. “The project also strengthens vital sovereign capability by training the next generation of Australian material researchers in cutting-edge transducer design,” Zhang said.

The researchers conducted successful field trials, acquiring data from a sonar transducer at Nelson Bay, Shoalhaven and Sydney, with strong performance across a range of conditions. The project demonstrates that a complete local supply chain in shallow water sonar systems can be established — spanning design, manufacturing, programming, control systems and data analysis — to deliver sophisticated sonar applications at smaller scales.

The system is now being assessed for potential commercialisation by industry partner CEE HydroSystems, an Australian manufacturer of hydrographic survey echo sounders and tide gauges.

Image caption: The project team conducted successful field trials, acquiring data from a sonar transducer on an unmanned surface vehicle, such as this one at Nelson Bay. Image credit: NSW Smart Sensing Network.