Security Need Not Be Expensive: Prototyping a Microcontroller-Based Smart Gate Towards Smart Boarding Houses

Abstract

Boarding house facility security is frequently compromised by manual padlocks, which are vulnerable to key duplication and create operational inefficiencies for security personnel. In comparison, commercial smart locks are often prohibitively expensive, susceptible to mechanical failure in outdoor environments, and limited in user credential storage capacity. This study designs, implements, and evaluates a cost-effective, microcontroller-based smart gate prototype as an efficient and reliable alternative. A five-stage prototyping methodology was employed: requirements gathering, rapid design, prototype development, user evaluation, and refinement. The system incorporates an ESP32 microcontroller integrated with an RFID scanner, numeric keypad, LCD display, and a 12V deadbolt solenoid actuator. Field testing involved directing all occupant circulation through a single sliding gate under real-world conditions to assess device functionality and durability. Results show that the dual authentication system validates access in under 850 milliseconds with an exceptionally low error rate of 0.19%. Furthermore, the system incorporates a practical hierarchical administrative feature that effectively distinguishes access rights, allowing managers to manage credentials independently via the keypad without requiring a computer. The prototype substantially optimizes operational budgets by eliminating recurring key duplication costs, while maintaining 100% operational uptime against outdoor weather conditions in Malang. However, the evaluation identified minor architectural limitations, including the absence of a gate-position feedback sensor and reduced LCD visibility under peak sunlight. Overall, the prototype demonstrates that robust security solutions can be achieved at a low cost, enabling secure, 24-hour independent mobility for residents while significantly reducing the workload of facility management.