Wireless pavement sensors for wide-area instrumentation

The vision for an autonomous pavement sensor, provisionally called Wisdom Stone (WS), is exposed. A WS is essentially an inertial sensor encapsulated in a rock-like casing that monitors accelerations, temperature, and sound at its embedment point. The envisioned unit can be wirelessly programmed to collect data at predefined dates and for predefined durations. The internally stored information may be wirelessly extracted in raw format or, after some internal analysis, in preprocessed format. The idea calls for a low-cost low-power design that can permit the deployment of many such (non-retrievable) WSs in any pavement layer and over wide areas. Results from a synthetic pavement model are analyzed in the time domain to determine the required sensing resolution, and in the frequency domain to guide the selection of data acquisition rate. Also described is the design and construction of a first generation working prototype, along with its firmware and controlling software.