GSM-Based Smart Fence Intrusion Detection and Alert System Using Laser Tripwire and Vibration Sensors

The escalating demand for automated security solutions has necessitated the evolution of traditional perimeter barriers into active surveillance systems. This study presents the design and implementation of a Smart Fence Intrusion Detection System, a low-cost, embedded solution aimed at mitigating unauthorized access in residential and commercial environments. The proposed system integrates a dual-sensor architecture controlled by an Arduino Uno microcontroller to detect distinct intrusion patterns: an SW-420 Vibration Sensor is utilized to identify structural disturbances associated with climbing, while a Laser Tripwire (Light Dependent Resistor and Laser Diode) monitors for physical breaches such as fence crossing. Upon the validation of an intrusion signal, the system executes a synchronized alert protocol consisting of a local audible deterrent via a 12V Siren and remote user notification through a SIM900A GSM V4.0 Module. A custom power distribution network, regulated by an LM2596S Buck Converter, ensures stable operation across the high-voltage alarm and low-voltage logic subsystems. Experimental results demonstrate that the system effectively differentiates between ambient environmental noise and actual security threats, delivering real-time SMS alerts with minimal latency. This research concludes that the integrated system offers a scalable, reliable, and cost-effective alternative to complex commercial surveillance architectures.