Closed loop systems are becoming the preferred method of operating coordinated traffic signal systems. Some of the benefits of a closed loop system include remote controller access, synchronization of controller time clocks, and orderly transition between coordination plans. With ensured time clock synchronization, the coordination of traffic signals becomes more reliable, which leads to optimal vehicle progression through the system. However, due to the complexity and relative infrequent implementation in more rural districts of closed loop systems, it is very difficult to obtain a successful deployment. This manual provides a step-by-step procedure for designing the parameters, implementing, testing, and field tuning closed loop systems. The procedure is described for an example closed loop system consisting of five intersections in West Lafayette, Indiana. The guidelines for the design of signal timing parameters will serve as a manual for all Indiana Department of Transportation districts. Detailed configuration procedures are provided for Econlite and Peek controllers, as well as their respective management software packages. Also included in the implementation procedure are instructions for interconnecting the controllers and establishing communication between the controllers. The testing procedure described in this manual is a hardware-in-the-loop simulation, which uses a controller interface device (CID) in conjunction with CORSIM software. Field tuning practices are documented for detectors, timing parameters, and coordination plans.

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traffic signal controller, closed loop system, signal timing calculations, hardware-in-the-loop simulation, field tuning, implementation, SPR-2390

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Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, IN

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