SCADA Traffic Light

    For my capstone project at WKU, I was tasked with creating a SCADA controller for a traffic light testbed present in one of our engineering laboratories. The controller was to be simple, built with Arduino and communicate over RS-232 via Modbus to an Allen-Bradley PLC wired directly into the testbed. Many of the difficulties included the communication scheme, the interface for UART to RS-232 conversion, and the timing sequences built into the PLC Ladder Logic. In the end, the simple HMI allowed for three modes of acquisition and control: It constantly queried and mirrored the state of the lights, It allowed us to implement a timing bias on different flows of traffic remotely, and it allowed us to detect traffic sitting at any of the stops. The project was a great success, and I look forward to working more with Allen-Bradley PLC's in my career.

The custom controller built for this application on an Arduino platform. The lights indicate the state of each pair of traffic lights in each direction, and the switches control the time-priority of traffic going each direction respectively.

The custom controller built for this application on an Arduino platform. The lights indicate the state of each pair of traffic lights in each direction, and the switches control the time-priority of traffic going each direction respectively.

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