SBIR Phase I: Wireless Weight in-Motion

This Small Business Innovation Research (SBIR) Phase I project will design, build and test a prototype wireless weigh-in-motion or W-WIM system. The proposed W-WIM system comprises an array of up to eight 3in cubes embedded in the pavement. Each cube contains a MeMS accelerometer, a microprocessor, and a radio that sends the accelerometer measurements to an access point on the side of the road. Each cube is powered by a battery, with a 10-year lifetime. The access point processes the accelerometer measurements to estimate the axle load, and transmits the estimates via GPRS to the traffic control center. The 3in cubes take up no space and can be installed in minutes, so W-WIM systems can be deployed anywhere. By contrast, today?s WIM systems use decades-old bending plate, piezoelectric or load cell sensors to measure axle load. These sensors take up a lot of space, and installing them requires shutting the lane to traffic for a long time. WIM systems need continuous calibration to maintain accuracy. They are expensive to build and operate. The broader impact/commerical potential of this project is high. Transportation agencies must prevent accelerated highway deterioration with diminishing funds for maintenance: costs have so escalated that $42 billion provided in SAFETEA-LU for 2009 Federal aid to highways will only be worth between $16.8 billion and $26.6 billion in 2005 dollars. One WIM station today costs $600,000 (plus support cost). The high cost and difficulty of installation limits WIM deployment. W-WIM systems will be priced at $60,000 per unit; since they are easy to install, they could be widely employed for comprehensive enforcement and data collection. W-WIM could be used on arterial streets to regulate trucks on city roads, where WIM systems cannot be used. W-WIM could be a component in a truck weight-based enforcement and toll system. WWIM could thus create a new market both within and outside the US that will employ people with diverse skills in the design, manufacturing, sales, and deployment of W-WIM systems.