Smart Solar Powered Pedestrian Crosswalk with Proximity Sensing and Cloud Alerts

Abstract

This study presents the design, prototyping, and empirical validation of an IoT-enabled, solar-powered pedestrian crosswalk for campus safety. Operating on solar energy, the system uses an LDR sensor for automated nighttime LED illumination and a push button to activate a dual-stage warning mechanism. Dual HC-SR04 ultrasonic sensors detect oncoming vehicles, triggering red LED alerts at 2.5 m and an audible siren with a Telegram cloud notification at 1.0 m. Multi-speed testing shows that the proximity sensors achieve 90% to 100% detection accuracy at speeds up to 20 km/h, degrading to 75% at 25 km/h due to sampling limits. Latency analysis reveals a highly responsive local hardware trigger of 41.5 ms, while cloud notification latency ranges from 1.25 s to 4.52 s depending on Wi-Fi signal strength (-52 dBm to -82 dBm). Under worst-case continuous load, the system consumes 37.25 W/h, offering 7.08 hours of battery autonomy without solar input. These quantitative results validate the system's viability for low-speed campus zones.