During the last decade considerable research and development efforts have been devoted to automating vehicles in an effort to improve safety and efficiency of vehicular traffic. While dedicated highways with fully automated vehicles is a future objective, the introduction of Intelligent Cruise Control (ICC) vehicles on current highways designed to operate with manually driven vehicles is a realistic near term objective. The purpose of this report is to analyse the effects on traffic flow characteristics and environment when ICC vehicles with automatic vehicle following capability (in the same lane) operate together with manually driven vehicles. We have shown that ICC vehicles do not contribute to the slinky effect phenomenon observed in today’s highway traffic when the lead manual vehicle performs smooth acceleration manoeuvres. We have demonstrated that ICC vehicles help smooth traffic flow by filtering the response of rapidly accelerating lead vehicles. The accurate speed tracking and the smooth response of the ICC vehicles designed for passenger comfort reduces fuel consumption and levels of pollutants of following vehicles. This reduction is significant when the lead manual vehicle performs rapid acceleration manoeuvres. We have demonstrated using simulations that the fuel consumption and pollution levels present in manual traffic simulated using a car following model that models the slinky effect behaviour observed in manual driving can be reduced during rapid acceleration transients by 28.5% and 1.5%-60.6% respectively due to the presence of 10% ICC vehicles. These environmental benefits are obtained without any adverse effects on the traffic flow rates. Experiments with actual vehicles are used to validate the theoretical and simulation results. (Author/publisher)
Samenvatting