Imagine an optic fiber that can sense the presence of a nearby jackhammer and warn its owner that it is in danger of being dug up, just in time to tell diggers not to sink another shaft. Next, imagine that an entire city's installed base of fiber could be turned into sensors that will make planners think twice before installing IoT devices.
As explained to The Register by Mark Englund, CEO of FiberSense, the company uses techniques derived from sonar to sense vibrations in fiber cables. FiberSense shoots lasers down the cables and observes the backscatter as the long strands of glass react to their environment.
"Vibration and sound all modulate strain in fiber," Englund explained, adding that even deeply buried fibers react to vibrations and sound. FiberSense has figured out how to measure changes in a fiber and deduce what made them.
The company can therefore detect things like passing traffic with sufficient accuracy to determine the difference between a truck and a cyclist, speed of travel, and even what lane a vehicle used. Leaky pipes can also be sensed, as can the geotechnical profile of spoil beneath fibers. Backhoes and jackhammers are easy.