A Framework for Urban C-ITS GLOSA Evaluation

Abstract

The use of the C-ITS Day1-service GLOSA - green light optimized speed advisory - in urban networks depends on various environmental and temporal constraints. While GLOSA generally is said to improve traffic flow and decrease emissions and delay, the availability may be actually very low in real world scenarios due to the aforementioned constraints. In this paper, a framework to evaluate the effectivity of GLOSA (measured as percent of the cycle time where it is available with high confidence) is proposed, considering the 1.current signal program parameters like cycle time or proportion of green per cycle,2.traffic flow parameters like traffic load or queue length and3.limitations on the lowest and highest possible speed advised by GLOSA as well as the range of communication depending on the communication technology. The paper presents the framework and shows its application to evaluate typical urban intersections equipped with V2X communication. For this network, the effectivity of GLOSA will be evaluated based on the access lanes of signalized intersections, and it will be shown, at which intersection and under which circumstances GLOSA makes sense. Furthermore, it will be estimated what level of service is achieved for GLOSA. The proposed framework to assess the C-ITS service GLOSA serves as a basis for evaluating the possibilities for connected and automated driving in other cities and urban corridors.