Sending power wirelessly through inches of steel

Published 26 July 2010

Submarines are made of very thick steel; this keeps them safe, but makes communication and data collection from sensors difficult; currently, 300 holes have to be drilled in a submarine hull to accommodate the sensors and communications technology the vessel requires; researchers develop a way to transmit power wirelessly through several inches of steel — which will allow submarines to communicate without an expensive hole-and-valve system; the technology will also be useful for the nuclear and oil industries

How does a submarine communicate with the outside world? Dr. John Bagshaw, a technology executive from BAE Systems Advanced Technology Centre in Bristol, explains that, currently, 300 holes have to be drilled in a submarine hull to accommodate the sensors and communications technology the vessel requires.

In each of these holes, they fit special valves called penetrators,” he explained. Each of these costs from £20,000 to £750,000 pounds. “It then costs up to £50,000 to weld the valves in to the holes, and through their life they have to be checked to ensure that the welds aren’t cracking.”

So through the 25-year life of a submarine, the total cost of all of its penetrators is in order of £80 million.”

BAE researchers have developed technology which may do away with the need to drill all these holes by allowing power to be transmitted wirelessly through several inches of steel. The BBC’s Victoria Gill reports that device could be used to send power and communications signals through submarine hulls or armored doors.

The device uses very high frequency acoustics — essentially converting the signal into sound waves.

The company has started environmental tests on the technology. “This is emerging technology and we have to make sure the engineering is perfect,” said Bagshaw.

Bagshaw added that, as well as military applications, the technology could potentially be useful in the nuclear and oil industry. “If you want sensors on the inside of a reactor vessel, you obviously don’t want to be drilling holes in that vessel,” he said.

Gill notes that one key aspect that the developers are yet to perfect is the adhesive that will be used to stick the connectors to the outside of a submarine or vehicle.