Streamlining of the Traffic Modeling Process for Implementation in the Twin Cities Freeway Network

Project summary:

This project responds to a need to streamline the traffic modeling process for practical implementation and thereby improve Minnesota Department of Transportation (Mn/DOT) engineers' productivity in view of the new federal requirements design and planning of roadway improvements. Streamlining will also improve decision making and allow more widespread use of simulation internally for design, planning, operations, maintenance and construction. The key element in improving traffic operations and infrastructure is the ability to assess the effectiveness of various alternatives prior to implementation. Simulation methods have long been recognized as the most effective tool for such analysis, and a number of simulators have been developed for analyzing freeway and/or arterial networks. Although a great deal of effort has been made for making simulation a suitable tool for practical applications, engineers still regard it as a complex tool. Such concerns are justified by the extensive manual labor required to enter the massive traffic and geometry data required by simulation programs, calibrate the model, extract the desired information from the simulation output, and interpret the results. As part of this project, several tools were developed to accelerate the simulation process; in the process, it became clear that better tools for obtaining high quality data for simulation purposes were required. In collaboration with Mn/DOT modelling group, the research team has developed an efficient methodology for detecting and correcting erroneous freeway loop detector data (temporal outliers,spatial discrepancy,locked-on data, missing data, stuck data etc). Particulary,this methodology includes an optimiztion-based algorithm for balancing freeway spacial discrepancies.