Assessment of Adaptive Traffic Signal Control Using Hardware in the Loop Simulation

Adaptive Traffic Signal Control (ATSC) can potentially mitigate traffic congestion. Research and development in the area of ATSC have produced a number of new systems with promising potential, however the performance of these systems under real-life conditions has been always a concern for practitioners as well as researchers, particularly if and how the new systems would be implementable in the field on controllers with specific capabilities and limitations. Therefore, testing and refining new ATSC systems on actual hardware and under representative traffic conditions prior to field implementation is essential to bridge this gap. In this paper, a hardware in-the-loop simulation (HILS) framework is developed to evaluate MARLIN, as an example of a new self-learning ATSC system. HILS is used for evaluating hardware components running the ATSC software in a simulation environment in which an actual traffic signal controller and an embedded computer are physically connected to a microscopic traffic simulator. Our focus is on the development, implementation of the HILS framework and the evaluation of MARLIN, on an intersection that suffers significant traffic fluctuation and delays - at the City of Burlington, Ontario, Canada. The performance of MARLIN-ATSC is demonstrated with HILS, which consists of a PEEK ATC-1000 traffic controller, an embedded computer running the ATSC system, and Paramics microscopic simulation model. HILS results indicated that MARLIN-ATSC has the potential to reduce the intersection average delay by up to 20% on average compared to the optimized and coordinated actuated signal timing plans.