Design and Construction of a Vehicle Detection Device Based on Nodemcu Ultrasonic Sensor and Running Text as Information

Driving safety is often compromised by limited visibility, particularly when behind large vehicles or on narrow roads and sharp bends, which can increase the risk of accidents due to inappropriate overtaking decisions. This research designed and built a vehicle detection device based on a NodeMCU ESP8266, an HC-SR04 ultrasonic sensor, and running text as an information medium. It is equipped with a Neo 6M GPS module and Telegram application integration as an IoT feature. The system works by detecting vehicles in front using an ultrasonic sensor. The NodeMCU then processes the data and displays the message "Overtaking is prohibited" or "Please Overtake" on the running text, while also sending the vehicle's location in real time via Telegram. The research used a prototype method with a waterfall model, starting from requirements analysis, design, implementation, and testing. Test results showed that the system is capable of providing clear visual information and accurate location notifications, thus assisting drivers in making safer decisions. However, several limitations were identified, including the ultrasonic sensor's instability in certain weather conditions, the GPS module's time-consuming signal acquisition in closed areas, and the running text's limited character set when configured directly through the program.