Development of a Wireless Stop Light Synchronization System for Single-lane Traffic Control

This paper presents a stop light control system for single-lane traffic based on wireless communication. The main system consists of two control boards. One control board is set as the sender and the other one is set as the receiver. Each board connects with a green stop light (go sign) and a red stop light (stop sign). The control boards use NodeMCU V.2 with 2.4 GHz WiFi modules to communicate each other by ESP-NOW protocol. The sender transmits the synchronous stop light control signal to the receiver. When the sender is a green light, the receiver would be a red light. The switching time of the stop light can be adjusted from the sender. The system has been tested in a real-world environment. The experimental results show that the proposed system can work correctly at all distances. The maximum working distance of this prototype system is recommended to be forty meters.