Fuzzy Variable Speed Limit Device Modification and Testing: Phase 2.

摘要

In 1998, Northern Arizona University (NAU) and the Arizona Department of Transportation (ADOT) designed and implemented the prototype of a variable speed limit (VSL) system for rural highways that utilizes information provided by a typical Road Weather Information Station (RWIS). This joint project produced a fuzzy logic control system that continuously displays highway speeds appropriate to the atmospheric and road surface conditions at locations of interest along the I-40 corridor in rural northern Arizona. Fuzzy logic is a system of mathematics that allows the vagueness of linguistic concepts to be represented by sets with imprecise boundaries. This report first discusses the upgrades and enhancements completed for the selected RWIS test site on I-40. This includes a discussion of sensor upgrades and additions at the RWIS site, new power sources made available to the site, and software improvements that support the RWIS enhancements. Following this is a discussion of the project software that was created in order to prepare for the analysis of the RWIS and traffic flow data that is being collected. A final section of conclusions and recommendations complete this report.