Smart Home System with ESP32, Alexa Control, and EEPROM State Retention

Introduction

In this project, we will create a smart home system that allows control over 14 devices and 1 air conditioner (AC) using an ESP32 microcontroller. The system includes EEPROM functionality, which retains the state of all devices even after a sudden power loss. With Alexa integration, users can control lights, fans, tube lights, AC, and more using voice commands and monitor the real-time status through the Alexa app. Each room is equipped with a 4-channel relay module, connected to a central controller that manages all relays.

This project is ideal for automating homes and integrating voice-controlled systems, making life easier and more efficient.

Components Required

To build this smart home system, you’ll need the following components:

  • ESP32 (central controller with Wi-Fi functionality)
  • 4-Channel Relay Modules (one per room)
  • EEPROM (to store device states)
  • Alexa-compatible devices (for voice control)
  • AC Module (for controlling air conditioner)
  • Power Supply (5V and 12V as required)
  • Jumper Wires
  • Connectors
  • PCB for custom circuit design (optional)
  • Resistors, Capacitors, Diodes, etc.
  • Breadboard for testing

Raw Media Files

These are the raw unedited photos, videos, and prototype tests. Click Here:

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How It Works

The ESP32 serves as the main controller for the entire smart home system. Each room has a 4-channel relay module, which controls the devices (e.g., lights, fans, etc.). The ESP32 sends signals to the relay modules based on user commands.

Key features include:

  1. Voice Control: Integrated with Alexa, users can control devices using voice commands.
  2. Real-time Monitoring: The status of each device is displayed and controlled through the Alexa app.
  3. EEPROM Functionality: In case of a power failure, the system retains the state of each device, ensuring continuity once power is restored.
  4. Centralized Control: A central controller manages all room relays, reducing wiring complexity and enabling seamless communication between rooms.

Step-by-Step Making Guide

Step 1: Gather Components

Collect all the components listed above, ensuring you have an ESP32, relay modules, EEPROM, and Alexa-compatible devices.

Step 2: Build the Circuit Prototype

Start by connecting the ESP32 to the 4-channel relay modules. Wire each room’s module to the central ESP32 controller. Ensure proper connections for the EEPROM and power supply.

Step 3: Program the ESP32

Using Arduino IDE or any other compatible platform, upload the code to the ESP32. The code should include the logic for relay control, Alexa voice integration, and EEPROM state retention. [Insert code or link to code here]

Step 4: Connect to Alexa

Set up the ESP32 to communicate with Alexa. You can use platforms like AWS IoT or ESP Alexa libraries. Ensure that each device (fan, light, etc.) is properly recognized in the Alexa app for voice and app control.

Step 5: Test the System

Once everything is connected, test each room by controlling devices with voice commands and the Alexa app. Ensure that the EEPROM correctly restores the device states after a power cut.

Step 6: Design and Assemble the PCB

After testing the prototype, move to PCB design for a more permanent solution. Assemble the components onto the PCB and test the system again.

Conclusion

This smart home system provides efficient, centralized control over various home appliances and devices. With features like Alexa voice control and real-time monitoring, the system offers a modern and convenient solution for home automation. The EEPROM functionality ensures device state retention, making the system reliable even in power outages.

Advantages

  • Centralized control over 14 devices and 1 AC unit.
  • Alexa voice control and real-time status monitoring via the Alexa app.
  • EEPROM functionality retains device states after power loss.
  • Modular relay system for easy expansion and customization.
  • Simple, user-friendly control interface through voice commands.

Disadvantages

  • Complex initial setup due to wiring and Alexa integration.
  • Requires reliable Wi-Fi for Alexa and real-time monitoring.
  • Limited to 14 devices unless more relays are added.

Future Scope for Improvement

  • Expand the number of devices controlled by adding more relay modules.
  • Integrate with other smart home platforms like Google Home or HomeKit.
  • Add support for remote control via mobile apps outside the Alexa ecosystem.
  • Improve power efficiency and incorporate energy-saving mechanisms for smart devices.
  • Battery backup to maintain system operation during power outages.