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Version: ACS CC

Mini Smart Home

A miniature smart home model featuring automated security, climate control, emergency hazard detection.

info

Author: Badea Andreea-Bianca
GitHub Project Link: link_to_github

Description

This project is a miniature smart home prototype designed to demonstrate practical home automation and safety features. It integrates an RFID-based security system for door access, alongside a climate control module that automatically adjusts windows based on real-time temperature and rain detection. For safety, it features an emergency hazard protocol that triggers an alarm and opens windows if smoke or gas is detected. Additionally, the system includes a built-in LCD screen for monitoring environmental data and a RGB lighting system, creating a complete, interactive model of modern smart living.

Motivation

I chose this project because I wanted to build something highly interactive that you can see working in real life. It is fascinating to learn how data from sensors can control physical movements, like unlocking a door with a card or automatically closing the windows when it rains. I also wanted to create a system that reacts to dangers, such as turning on an alarm and opening windows if it detects smoke or gas. Building this model is a great and simple way to learn how to connect sensors, motors, and lights together.

Architecture

The final system will include modules for: Environment sensing:

  • Digital temperature and humidity sensor (DHT11).

  • Rain sensor (detects precipitation to trigger window and awning control).

  • Gas and smoke sensor (MQ2) for safety monitoring.

Output feedback: LCD 1602 display with an I2C interface, for showing system status (e.g., temperature, humidity, "Emergency Mode", system alerts).

Motorized components: Two SG90 servo motors: one for door access, one for window control.

Input system: RC522 RFID module for scanning the access card.

Indicators: RGB LED module and an active buzzer (for alarms).

SchemaBlock

Log

Week 5 - 11 May

Week 12 - 18 May

Week 19 - 25 May

Hardware

The system is built around the STM32 Nucleo-U545RE-Q microcontroller. The sensory hardware includes a DHT11 temperature and humidity sensor , a rain sensor , an MQ2 gas/smoke sensor for safety , and an RC522 RFID module for secure access. Outputs and physical movements are driven by SG90 servomotors , an active buzzer , an RGB LED module , and an I2C-enabled LCD1602 screen for displaying system data.

Schematics

Schematics

Bill of Materials

DeviceUsagePrice
STM32 Nucleo-U545RE-QThe microcontrollerLab Provided
SG90 Servo MotorControls door/window9.99 RON
RC522 RFID ModuleAccess control14.99 RON
DHT11 Temperature & Humidity SensorIndoor climate monitor7.99 RON
MQ2 Gas Sensor ModuleHazard and smoke detector11.99 RON
RGB LED ModuleVisual status indicator2.13 RON
LCD1602 Display with I2C/IIC ModuleSystem data screen24.99 RON
Rain sensorRain sensor6.99 RON

Software

LibraryDescriptionUsage
st7789Display driver for ST7789Used for the display for the Pico Explorer Base
embedded-graphics2D graphics libraryUsed for drawing to the display
  1. DIY Smart Home