This Small Business Innovation Research (SBIR) Phase II project will develop a fully functional prototype of an accelerometer-based wireless Weigh In Motion (WIM) station. The WIM system will comprise an array of battery-powered 3? cubes, embedded in the pavement, each consisting of an accelerometer, a microprocessor for local signal processing, and a radio that sends the processed measurements to an Access Point (AP) on the side of the road. The AP estimates the pavement load from each axle of a truck at freeway speeds and the truck?s class, and transmits these estimates to the traffic management center. The cubes take up minimal space and are installed within minutes, so WIM systems can be deployed anywhere at a fraction of the cost of traditional WIM stations. Phase I research demonstrated the technical feasibility and commercial potential of the WIM. The technical objectives of Phase II concern the WIM packaging and installation; calibration: sensitivity to weight, speed and temperature (especially for asphalt pavements); signal compression and source coding; channel coding; wide area data backhaul; overall system design; manufacturing prototype samples; and extensive testing. <br/><br/>The broader impact/commercial potential of this project is to dramatically enhance the regulation of truck weights and provide data to greatly improve the maintenance of the US road and bridge infrastructure by drastically reducing the costs of WIM stations. Current WIM stations have limited deployment as they are costly to install requiring shutting the road for days and needing expensive maintenance and re-calibration. The new WIM stations could be widely deployed in additional locations on arterial streets and near ports to monitor truck traffic and be a component in a truck weight-based enforcement and toll system. These WIM stations could also meet similar objectives in overseas markets creating employment for US residents with diverse skills in the design, manufacturing, sales, and installation.