Solar-powered Underwater Robots Unveiled

Held at the National Science Foundation (NSF) in Arlington, Virginia, the World Technology Evaluation Center International Study of Robotics is a two-year look at robotics research and development in the United States, Japan, Korea, and Western Europe.

As the principal investigator of an NSF-funded project called RiverNet, Arthur C. Sanderson, professor of electrical, computer, and systems engineering at Rensselaer Polytechnic Institute is working collaboratively with other researchers to develop a network of distributed sensing devices and water-monitoring robots, including the first solar-powered autonomous underwater vehicles (SAUVs).

The SAUV technology allows underwater robots to be deployed long-term by using solar power to replenish onboard energy. Long-term deployment of SAUVs will allow detection of chemical and biological trends in lakes, rivers, and waterways that may guide the management and improvement of water quality. Autonomous underwater vehicles equipped with sensors are currently used for water monitoring, but must be taken out of the water frequently to recharge the batteries.

"Once fully realized, this underwater robot technology will allow better observation and monitoring of complex aquatic systems, and will support advances in basic environmental science as well as applications to environmental management and security and defense programs," said Sanderson.

According to Sanderson, the SAUVs communicate and network with one another in real time to assess a water body as a whole in measuring how it changes over space and time. Key technologies used in SAUVs include integrated sensor microsystems, pervasive computing, wireless communications, and sensor mobility with robotics. Sanderson notes that the underwater vehicles have captured the attention of the U.S. Navy, which will evaluate their use for coastal surveillance applications.

The SAUV weighs 370 pounds, travels at speeds of up to 2 miles per hour, and is designed to dive to depths of 500 meters.

Sanderson and his colleagues will continue field testing the vehicles in coming months at locations including Rensselaer's Darrin Fresh Water Institute on Lake George, N.Y., to determine communication, interaction, and maneuvering capabilities in testing dissolved oxygen levels, one of the most important indicators of water quality for aquatic life.

Sanderson is collaborating on SAUV development with the Autonomous Undersea Systems Institute, Falmouth Scientific Inc., the Naval Undersea Warfare Center, and Technology Systems Inc.