Leveraging Traffic-in-the-Loop Simulations to Assess the Impact of Traffic on Vehicle Energy Consumption

The advancements in vehicle connectivity and the increased level of driving automation can be leveraged for the development of advanced driver assistance systems (ADAS) that improve driver safety and comfort while optimizing the energy consumption of the vehicle. In the development phase of energy-efficient ADAS, modeling and simulation are used to assess the potential benefits of these technologies on energy consumption. However, there is a lack of standardized simulation or test frameworks to quantify the benefits. Moreover, the driving scenario and the traffic conditions are often not explicitly modeled when simulating energy-efficient ADAS, even though they have a major impact on the attainable energy benefits. This paper presents the development and implementation of a closed-loop traffic-in-the-loop simulator designed to evaluate the performance of vehicles under realistic traffic conditions. The primary objective is to assess how varying traffic conditions influence vehicle energy consumption along a predefined route, highlighting the importance of considering traffic during the development of energy-efficient vehicle controllers. By integrating a dynamic microtraffic model from the open-source software SUMO with a high-fidelity vehicle model in Simulink, the traffic-in-the-loop simulator provides a comprehensive platform for analyzing the impact of traffic on vehicle efficiency. The microtraffic model is controlled online through a Matlab script leveraging TraCI, a TCP based client/server architecture that allows to retrieve values of simulated objects in SUMO and to manipulate their behavior. The findings demonstrate the significant impact of traffic conditions on vehicle energy consumption, highlighting the necessity of simulating traffic environments to properly evaluate the potential benefits of advanced vehicle technologies.