When it comes to mapping the ocean floor, lasers can capture fine details even better than the sonar. However, while sound waves excel at cutting through dense materials, light waves move best through empty space, making it difficult for lasers to penetrate the ocean's murky depths.

Researchers from Florida Atlantic University's Harbor Branch Oceanographic Institute think it's possible to overcome the problems of undersea laser imaging by deploying swarms of automated robots to do the job.

Working together, these bots could function as a giant laser-imaging network and provide broader, faster coverage of the ocean's bottom. The approach could aid in the identification of objects (such as mines) that endanger shipping and military operations, researchers say.

These robotic laser networks may also provide a more holistic view into the ecology of endangered coral reef habitats, says Fraser Dalgleish, the project's principal investigator and an assistant research professor at Harbor Branch in Fort Pierce, Fla.

To do this, the researchers are developing computer simulation models to determine the best methods for undersea laser imaging and data communications. The variables include water depth, cloudiness, and the limits of the laser imaging technology itself, Dalgleish explains.

In one possible laser-networking scenario, robots closest to the seabed would be used to illuminate areas of interest. Images would be transmitted a robot located higher up in the water column that could act like optical modem, relaying image data back to a vessel on the surface. In shallower water, the image could be sent to the vessel directly by the robot scanning the seabed.

The Defense Department's Office of Naval Research in March awarded Harbor Branch scientists with a $2 million grant to work on the approach.

Images depicting one possible underwater laser imaging and communications system concept courtesy of Fraser Dalgleish/ Harbor Branch Oceanographic Institute