Smart Home Security System

Mobile App

Overview

Smart Home Security System built with Arduino Uno R3, ESP32, Firebase, and a Kotlin Android application using Jetpack Compose and MVVM architecture. The system monitors multiple sensors in real time and provides feedback through the mobile app.

Technologies used (Mobile App)

• Navigation Bar – Home, History (currently in development), and Profile screens.
• Firebase Authentication – Login, Sign up, and Sign out (with valid Arduino ID).
• Firebase Realtime Database – Stores and updates sensor states in real time.
• Firebase Firestore – Stores user profiles and Arduino IDs.
• MVVM & LiveData – separates logic from views, manages user authentication, profile, and real-time sensor data on Home screen.

Built With

• Android Studio Kotlin Jetpack Compose, MVVM
• Arduino IDE C++
• Firebase authentication, Realtime Database and Firestore
• Arduino Uno R3, ESP32
• Full-size and half-size breadboards
• Led diode + 220 Ohm
• Pushbutton switch 12mm + 1k Ohm
• Buzzer
• Passive infrared sensor HC SR501
• Door (servo – Open/Closed state)
• Resistor
• RFID Card
• Voltage divider 5V(Arduino Uno R3) to 3.3V(ESP32), 2.2k Ohm + 1k Ohm
• Water Level
• DHT11 temperature and humidity sensor
• Serial communication (Arduino Uno R3 ↔ ESP32)

Circuit Schema

Demonstrations

• Google Drive Videos
• Screenshots of the Android app

  Profile	Home	Signup

  Login	Alarm	Alarm & Flooding

  How It Works

  • Arduino Uno R3
    • Collects sensor data:
      • Alarm → true/false
      • PIR sensor → true/false
      • Temperature & Humidity → numerical values
      • Water Level → true/false
      • Switch button stops the active alarm after 5 seconds, then the system restarts.
      • Sends these values to the ESP32 via Serial communication, pin TX0 (Arduino Uno R3) → Voltage divider (5V → 3.3V) → pin 16GPIO (ESP32).
  • ESP32
    • Reads the Serial output from Arduino Uno R3.
    • Servo motor controls door (Open/Closed) with a valid RFID card.
    • Sends all sensor values and states to Firebase Realtime Database
  • Android App (Kotlin, Jetpack Compose, MVVM)
    • Reads data from Firebase in real time.
    • Displays live sensor values.
    • Vibration & red text alerts when Alarm, PIR, or Water Level are triggered
    • Provides door control (servo Open/Closed).
    • User login, registration, profile, and sign out (requires valid Arduino ID).