A networked, autonomous smart locker system built on the STM32 platform. This project provides a scalable, secure, and low-cost alternative to manual lockers by integrating environmental monitoring, proximity-based power management, and a distributed Master-Slave architecture. 📖 Overview
The system is designed with a modular architecture where a Master Controller manages multiple Locker Nodes. It ensures secure storage for sensitive items (e.g., in labs, banks, or P.O. boxes) by monitoring internal conditions and restricting access via PIN authentication .
✨ Key Features
Distributed Architecture: Uses RS-485/UART for reliable multi-node communication between the Master and individual Lockers.
Environmental Monitoring: Each locker is equipped with Humidity and Temperature sensors (DHT22/BME280) to protect sensitive items.
Power Efficiency: Integrated Proximity Sensors (PIR/IR) enable "Sleep Mode," waking the system only when a user approaches.
Secure Access: Matrix keypad input for local PIN authentication at the locker level.
Status Display: Centralized LCD interface on the Master node for system status and user feedback.
🛠 Hardware Specifications
The project utilizes the STM32F401 "Black Pill" for both Master and Locker nodes due to its rich peripheral set (UART, I2C, SPI) and industrial reliability . Master Unit
Microcontroller: STM32F401 (Black Pill)
Display: 16x2 LCD (I2C)
Sensors: Proximity Sensor (for system wake-up)
Interface: Buttons for system control
Locker Unit (Per Locker)
Microcontroller: STM32F401 (Black Pill)
Actuator: Servo Motor (Locking Mechanism)
Input: Matrix Keypad
Sensors: Humidity & Temperature Sensor
📂 Repository Structure
Master/: Firmware for the central STM32 unit. Handles UI (LCD), global power states (Proximity), and RS-485 coordination.
Locker/: Firmware for the individual locker nodes. Handles keypad reading, servo actuation, and environmental data reporting.
🚀 Getting Started Prerequisites
Toolchain: STM32CubeIDE or arm-none-eabi-gcc with Make.
Hardware: 3x STM32F401 Boards, RS-485 Modules, Sensors, and Servos.
Installation
Clone the Repository
Flash the Master Connect your Master STM32 via ST-Link.
Flash the Lockers Connect your Locker STM32 via ST-Link.
👥 Team Members
Manas Viswajith (cb.sc.u4cse23337)
Nandagopal Menon (cb.sc.u4cse23340)
Dharshini P (cb.sc.u4cse23342)
Roshini (cb.sc.u4cse23345)