Impact Evaluation of a Driving Support System on Traffic Flow by Microscopic Traffic Simulation

Abstract

This article reports on a study that evaluated a driving support system by using a microscopic traffic simulation which was modified by adding the function of perception-response process. In this approach, a dangerous driving situation is assessed by detecting conflict through simulation. The authors defined a safety indicator named TIDSS (Time Integral of Difference of Space distance and Stopping distance) from the time integral of the relative distance between the leading and following vehicle when the leading vehicle brakes suddenly. They contend that this indicator is superior to existing indicators because it can evaluate any type of situation and can include the degree and duration of danger for each vehicle. The authors tested their proposed approach by using it to evaluate the adaptive cruise control system (ACC) and automated platoon system (APS) for heavy trucks on an urban expressway. Many cases with different installation rates of ACC and APS were simulated using the proposed approach, and the relation between installation rate, safety indicators, and traffic flow rate was analyzed. They conclude that the results support the use of ACC to mitigate dangerous situations on the expressway by decreasing the traffic flow rate. Alternately, introduction of APS might mitigate dangerous situations and also increase the traffic flow rate.