Improving intersection safety through variable speed limits for connected vehicles
Principal Investigator(s):Michael Levin, Assistant Professor, Civil, Environmental and Geo-Engineering
- Chen-Fu Liao, Researcher, Mechanical Engineering
Autonomous vehicles create new opportunities for innovative intelligent traffic systems. Variable speed limits (VSLs), which are speed-management systems that can adjust the speed limit according to traffic conditions or a predefined speed-control algorithm on different road segments, can be better implemented with the cooperation of autonomous vehicles. These compliant vehicles can automatically follow speed limits. However, non-compliant vehicles will attempt to pass the moving bottleneck created by the compliant vehicle. This project builds a multi-class, cell-transmission model to represent the relationship between traffic-flow parameters. This model calculates flows of both compliant and non-compliant vehicles. An algorithm is proposed to calculate variable speed limits for each cell of the cell-transmission model. This control algorithm is designed to reduce the stop-and-go behavior of vehicles at traffic signals. Simulation is used to test the effects of VSLs on an example network. The result shows that VSLs are effective at reducing the energy consumption of the whole system and they reduce the likelihood of crash occurrence.