The first 20 prototype infrastructure sensors installed in 2016 on the Mackinac Bridge, powered solely by vibrations from traffic, have proven their durability and performed as intended. Now researchers from Michigan State University and Washington University in St. Louis are ready to roll out the next phase of testing, installing up to 2,000 of the tiny devices to explore the logistics of a large-scale deployment and provide useful monitoring data to the Mackinac Bridge Authority.