Underwater wireless communication has long been one of the biggest roadblocks in exploring and understanding the ocean. The main reason is that water absorbs nearly the entire spectrum of electromagnetic waves, including radio signals, Wi-Fi, and GPS; making most everyday wireless technologies useless underwater. Sonar, which uses sound instead of electromagnetic waves, can travel much farther through water, but it’s slow and can only send small amounts of data. This makes it nearly impossible to control underwater robots in real time or to quickly respond to underwater emergencies. As a result, most of the ocean remains unexplored, and even high-stakes missions like the search for lost aircraft or deep-sea environmental disasters face major delays. There is also growing interest in the deep sea for mining rare minerals and finding new medicines, but without reliable communication, these efforts are risky and limited.

To address this, we created and successfully tested a new system that uses a group of small underwater robots to pass a laser signal underwater. These robots form a moving chain, like a relay team, passing high-speed data through the water in a way that’s never been done before. Before building the robots, we developed a smart computer model to understand how the system would behave in real ocean conditions, where water currents can push and pull in unpredictable ways. We trained this model using artificial intelligence to predict how currents would change, and used that information to help the robots stay in place and keep the signal stable.

We then built five compact, highly agile underwater robots. They are designed to stay steady and accurately aim their laser beams, even while moving through the water. Each robot includes advanced internal parts that keep it balanced and allow it to steer the laser with great precision; something that's necessary for underwater laser communication to work. The system is also designed so that if any one robot fails or runs out of battery, another can quickly take over, so the link is never broken.

The full system was tested in a large water tank under controlled conditions. The robots were able to successfully pass along a laser signal over a distance, and we were able to send live video from underwater to the surface; something sonar cannot do. This proves that high-speed underwater communication is not only possible, but practical.

Alongside the technical accomplishments, this project also served as a powerful educational experience. Three PhD students, nine Master’s students, and twenty-five undergraduate students were involved throughout the research. They received hands-on training in designing experiments, developing technology, analyzing data, and writing scientific theses. For many of them, this was their first experience contributing to real-world research, and the skills they gained will carry forward into future academic and professional work. The results of this research have been documented through peer-reviewed journal publications, conference proceedings, and book chapters. In addition, patents were filed based on the technologies developed, and one of the PhD students involved in the project has established a startup company to further develop and commercialize the system.

With this success, underwater missions could consider including live communication, making deep-sea research, underwater mining, disaster response, and even drug discovery much faster, safer, and more effective. This is a major leap forward in our ability to connect with, explore, and protect the ocean.

Last Modified: 03/29/2025
Modified by: Reza Alam