Development of a Low-Cost Iot-Enabled Queue Management System Using ESP32, ESP-NOW, and Offline Audio-Visual Feedback for Enhanced Service Delivery

Abstract

Managing queues effectively is a major hurdle in both healthcare and banking sectors, where long wait times and a lack of information can really dampen customer satisfaction and hurt operational efficiency. Traditional methods, like paper token systems and basic digital displays, often overlook the psychological stress that comes with uncertainty and don’t cater well to those with visual impairments. This paper introduces a smart queue management system that combines wireless communication, web-based registration, and synchronized audio-visual notifications. The system uses two ESP32 microcontrollers that talk to each other via the ESP-NOW protocol; one acts as the operator controller with a keypad and OLED display, while the other runs a dot-matrix LED display and can announce messages offline. A local web server allows users to register for the queue digitally through their mobile devices, and for those without smartphones, manual token generation is available. The audio system plays pre-recorded speech clips stored in flash memory to announce queue tokens, making it accessible for visually impaired users. Performance tests showed reliable wireless communication, precise token generation and queue progression, synchronized display and audio notifications, and effective offline operation. The system significantly enhanced queue accessibility and operational efficiency, boasting response times under 100 milliseconds and 100% transmission reliability within its range. This affordable and accessible solution offers a solid framework for modernizing queue management in settings with limited resources while ensuring inclusivity.