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.