ATMS Evaluation Procedures

SUMMARY Formal evaluation procedures for new advanced traffic management systems are essential for documenting ITS benefits. Such procedures are also very important during the " turn-on " phase of a deployment so those government agencies managing the deployment have quantifiable measures to determine that a system is working as specified. Current ATMS evaluation procedures during deployment require that probe vehicles be driven in the study area and their travel time between intersections and intermediate checkpoints be recorded. Since demand traffic volumes vary considerably from minute to minute and day to day, many travel time runs must be conducted. This paper documents an alternative " hardware-in-the-loop " evaluation procedure where the CORSIM traffic model simulates the vehicle demand, but the control strategy is run on the actual equipment that will be placed in the field. A controller interface device (CID) is used to provide the real-time linkage between CORSIM and the traffic signal control equipment. Travel times of probe vehicles in the simulation are recorded and tabulated just as they would be if technicians drove within the study area. This new " hardware-in-the-loop " evaluation procedure has the following benefits: 1)Before/after studies can be performed under specified demand volumes; 2)Expensive field travel time studies do not need to be conducted; 3)A suite of controlled traffic events can be developed and used during the acceptance testing phase to determine that the system performs as specified. 2 Bullock et. al.