An external logic processor for NTCIP-based traffic controllers: Proof of concept for data exchange capability

This paper presents a microprocessor-based device, external to a traffic controller, to communicate with the traffic controller through the Ethernet port using the NTCIP 1202 communication protocol. With such data exchange capabilities, it provides opportunities for real-time feedback control at the local intersection level. The paper presents the results of five tests to verify and validate the data exchange capabilities of the microprocessor-based device. The test results show that the microprocessor successfully used NTCIP data objects to read the controller´s detector status, phase status, and coordination parameters. The recommended hardware arrangement has clear potential to detect different traffic conditions such as cycle failure or queue spillback. In addition, the microprocessor detects phase states and phase sequences with sufficient accuracy to support assessing traffic conditions and determining efficient control strategies. Finally, the writing tests show that the microprocessor-based device can write to different controller parameters in an accurate and timely fashion, which is important for implementing real-time feedback control strategies.