ST. IGNACE, MI (AP)-- Engineers are using the Mackinac Bridge to test a new type of sensor that will monitor how the nearly 5-mile-long structure is coping with all those cars and trucks.
Professors from Michigan State University and Washington University in St. Louis are placing six prototype sensors beneath the bridge Wednesday. The bridge links Michigan's two peninsulas and crosses the waterway where Lakes Huron and Michigan meet.
The sensors are powered by vibrations that traffic generates. Most sensors that monitor bridge conditions depend on batteries or wires and need frequent maintenance. But these prototypes have no external power source.
The information they gather can be accessed wirelessly by someone driving over the bridge with a laptop.
If they perform well, more sensors may be installed next year.
