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The Minnesota Local Road Research Board, MnDOT, and SRF performed an evaluation of a portable weigh-inmotion (WIM) system at several locations throughout Minnesota. The system was developed at the University of Minnesota-Duluth and offers roadway designers a low-cost method for obtaining vehicle load distribution data across the state's road network. To deploy the system, the weigh pads of the system were temporarily affixed sensors across the roadway lanes. As vehicles passed over the weigh pads, pressure sensors within the pads detected the weight of vehicles and the system recorded the data for later analysis. Traditional methods for travel monitoring generate traffic volume and classification data, but weigh-in-motion systems give designers a more accurate idea of current and projected traffic loading demands. SRF's testing provided implementation refinements that were incorporated into the system. During the two-year deployment process, the portable WIM system was installed under a wide array of environmental conditions to demonstrate the system's capabilities. Data generated by the system was analyzed. The Final Report details system deployment, calibration, and system accuracy.

Conventional methods for detecting vehicles for permanent travel monitoring stations have relied on detecting physical attributes of vehicles without correlating these with the specific vehicles and/or motor vehicle freight operators. However, by using a license plate reader camera, information can be gathered and cross referenced to other known data related to the specific vehicle assigned to the license plate. This could provide additional tools for enforcing overweight vehicles or targeting enforcement communication with freight carriers that consistently violate weight limits. The analysis conducted during this project compared machine-read license plates to manually collected license plates. The license plates were read as vehicle travelled highway speeds in a generally uncontrolled environment. Analysis is also provided that correlates hours of direct sunlight with accuracy of the automated reader. A second analysis was conducted as an effort to improve the accuracy of the Minnesota Department of Transportation's weigh-in-motion classification scheme and bring it in line with the Department's classification scheme for automatic traffic recorder stations (sites with axle-based detection that do not collect weight information).