November 6, 2014

About the Presentation

Active Traffic Management (ATM) strategies are being deployed in major cities worldwide to deal with congestion and safety concerns. In the Twin Cities metro area, an ATM strategy involving Intelligent Lane Control Signs was deployed, allowing for the implementation of variable speed limits (VSL). This system aims to detect congestion and warn upstream drivers to lower their speed, thereby reducing the severe change in speed between upstream and downstream traffic and providing safety and operational benefits.

This presentation discussed an investigation of the I-94 VSL system's effects on safety in a high-frequency crash area. Using the unique capabilities of the Minnesota Traffic Observatory's I-94 Freeway Lab, high-resolution traffic measurements were collected by machine vision sensors at the bottleneck location. These measurements were then used within a new analysis methodology to measure and visualize shockwave activity before and after the implementation of the VSL system.

About the Speaker

John Hourdos

John Hourdos is the director of the Minnesota Traffic Observatory and a research scholar at the Center for Transportation Studies at the University of Minnesota. During the last six years, he has focused on research in traffic safety, specifically on the early detection of freeway traffic crash-prone conditions, the causal analysis of crashes, and the modeling of driver behavior related to crashes and near-crashes.