Gas Detector and Seismic Alert System for Home/Industrial Sa

// Project : Gas Detector and Seismic Alert for Security
// Board: RAK4631 (Nordic NRF52840)
// Base: RAK1903
// Sensors: RAK12035 MQ2 Gas Sensor, RAK12047 Dimron D75 Earthquake Sensor, RAK12033 IM-42652 6-axis Accelerometer
// Display: RAK1821 OLED
// LoRaWAN Platform: The Things Stack
 
#include <Wire.h>
#include <Adafruit_GFX.h>    // For OLED
#include <Adafruit_SSD1306.h> // For OLED
#include <LoRaWan-RAK4631.h> // LoRaWAN library for RAK4631
#include <SPI.h>
 
// Library for accelerometer (example, may vary based on exact IM-42652 model)
// #include <Adafruit_LIS3DH.h> // If using LIS3DH
// For IM-42652, you might need a library like SparkFun_ICM-20948_Arduino_Library or similar,
// or read directly via I2C/SPI. We'll use a simplified placeholder.
 
// LoRaWAN Configuration (OTAA) - REPLACE WITH YOUR THE THINGS STACK CREDENTIALS!
uint8_t nodeDeviceEUI[8] = {0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX};
uint8_t nodeAppEUI[8] = {0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX};
uint8_t nodeAppKey[16] = {0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX, 0xXX};
 
// LoRaWAN Region Configuration
LoRaMacRegion_t loraWanRegion = LORAMAC_REGION_EU868;
 
// Sensor Pins
#define MQ2_GAS_SENSOR_PIN WB_A0 // Analog pin for MQ2 gas sensor
#define EARTHQUAKE_SENSOR_PIN WB_IO1 // Digital pin for D75 earthquake sensor
 
#define OLED_RESET -1 // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
 
// Instances
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET); // I2C for OLED
// Adafruit_LIS3DH accel = Adafruit_LIS3DH(); // If using LIS3DH
 
// Variables to store readings and states
int mq2_gas_value;
bool earthquake_detected = false;
float accel_x, accel_y, accel_z;
bool movement_detected = false;
 
void setup() {
  Serial.begin(115200);
  delay(100);
  Serial.println("Starting IoT Security Detector...");
 
  Wire.begin();
 
  // Initialize OLED
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  display.display();
  delay(2000);
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0,0);
  display.println("Starting...");
  display.display();
 
  // Initialize sensor pins
  pinMode(MQ2_GAS_SENSOR_PIN, INPUT);
  pinMode(EARTHQUAKE_SENSOR_PIN, INPUT); // D75 is digital
 
  // Initialize accelerometer (placeholder)
  // if (!accel.begin(0x18)) { // LIS3DH I2C address
  //   Serial.println("Could not find accelerometer, check wiring!");
  //   display.clearDisplay(); display.setCursor(0,0); display.println("Error Accel!"); display.display();
  //   while (1);
  // }
  // accel.setRange(LIS3DH_RANGE_4_G); // Configure range
 
  // Initialize LoRaWAN
  if (api.lorawan.setRegion(loraWanRegion)) {
    Serial.printf("LoRaWAN region set to %d\n", loraWanRegion);
  } else {
    Serial.println("Failed to set LoRaWAN region.");
    while (1);
  }
 
  if (api.lorawan.setAppKey(nodeAppKey) &&
     api.lorawan.setAppEUI(nodeAppEUI) &&
     api.lorawan.setDevEUI(nodeDeviceEUI)) {
    Serial.println("LoRaWAN credentials configured.");
  } else {
    Serial.println("Failed to configure LoRaWAN credentials.");
    while (1);
  }
 
  Serial.println("Attempting to join LoRaWAN network (OTAA)...");
  display.clearDisplay(); display.setCursor(0,0); display.println("Joining LoRaWAN..."); display.display();
  if (api.lorawan.join()) {
    Serial.println("Joined LoRaWAN network!");
    display.clearDisplay(); display.setCursor(0,0); display.println("Joined LoRaWAN!"); display.display();
  } else {
    Serial.println("Failed to join LoRaWAN network. Retrying...");
    display.clearDisplay(); display.setCursor(0,0); display.println("Join Failed!"); display.display();
    while(1);
  }
  delay(2000);
}
 
void loop() {
  readSensors();
  displayData();
 
  // Send alert only if something is detected
  if (mq2_gas_value > 700 || earthquake_detected || movement_detected) { // Alert thresholds
    sendLoRaWANAlert();
    delay(5000); // Small pause after sending alert
  }
 
  Serial.println("Entering low power mode...");
  api.system.sleep.all(10000); // Sleep for 10 seconds for constant monitoring
}
 
void readSensors() {
  // Read MQ2 gas sensor
  mq2_gas_value = analogRead(MQ2_GAS_SENSOR_PIN);
  Serial.printf("MQ2 Gas: %d\n", mq2_gas_value);
 
  // Read D75 earthquake sensor
  earthquake_detected = (digitalRead(EARTHQUAKE_SENSOR_PIN) == LOW); // Assuming LOW when detected
  Serial.printf("Earthquake D75: %s\n", earthquake_detected? "DETECTED" : "NORMAL");
 
  // Read accelerometer (placeholder)
  // sensors_event_t event;
  // accel.getEvent(&event);
  // accel_x = event.acceleration.x;
  // accel_y = event.acceleration.y;
  // accel_z = event.acceleration.z;
  // Serial.printf("Accel X: %.2f, Y: %.2f, Z: %.2f\n", accel_x, accel_y, accel_z);
 
  // Simple movement detection logic with accelerometer (placeholder)
  // movement_detected = (abs(accel_x) > 1.0 || abs(accel_y) > 1.0 || abs(accel_z) > 1.0); // Movement threshold
  movement_detected = false; // Placeholder if actual accelerometer is not used
  Serial.printf("Movement: %s\n", movement_detected? "DETECTED" : "NORMAL");
}
 
void displayData() {
  display.clearDisplay();
  display.setCursor(0,0);
  display.printf("Gas: %d\n", mq2_gas_value);
  display.printf("Seismic: %s\n", earthquake_detected? "ALERT!" : "OK");
  display.printf("Move: %s\n", movement_detected? "ALERT!" : "OK");
 
  if (mq2_gas_value > 700) {
    display.setCursor(0, 40);
    display.println("HIGH GAS!");
  }
  if (earthquake_detected) {
    display.setCursor(0, 50);
    display.println("SEISMIC DETECTED!");
  }
  if (movement_detected) {
    display.setCursor(0, 50); // Might overlap, adjust position
    display.println("MOVEMENT!");
  }
  display.display();
}
 
void sendLoRaWANAlert() {
  // Alert payload format:
  // Byte 0: Alert Type (1=Gas, 2=Seismic, 3=Movement)
  // Byte 1: Severity (1=Low, 2=Medium, 3=High)
  uint8_t payload[2]; // Changed from 5 to 2 based on description
 
  if (mq2_gas_value > 700) {
    payload[0] = 1; // Type: Gas
    payload[1] = 3; // Severity: High
    Serial.println("Sending HIGH GAS alert!");
  } else if (earthquake_detected) {
    payload[0] = 2; // Type: Seismic
    payload[1] = 3; // Severity: High
    Serial.println("Sending SEISMIC alert!");
  } else if (movement_detected) {
    payload[0] = 3; // Type: Movement
    payload[1] = 2; // Severity: Medium
    Serial.println("Sending MOVEMENT alert!");
  } else {
    return; // No alert to send
  }
 
  if (api.lorawan.send(sizeof(payload), payload, 1, true)) { // Port 1, confirmed
    Serial.println("LoRaWAN alert sent successfully.");
  } else {
    Serial.println("Failed to send LoRaWAN alert.");
  }
}
 
// Example Payload Formatter (Decoder) for The Things Stack (Custom Javascript)
/*
function decodeUplink(input) {
  var data = {};
  var bytes = input.bytes;
 
  var alertType = bytes[0];
  var severity = bytes[1];
 
  switch (alertType) {
    case 1:
      data.alert_type = "Gas";
      break;
    case 2:
      data.alert_type = "Seismic";
      break;
    case 3:
      data.alert_type = "Movement";
      break;
    default:
      data.alert_type = "Unknown";
  }
 
  switch (severity) {
    case 1:
      data.severity = "Low";
      break;
    case 2:
      data.severity = "Medium";
      break;
    case 3:
      data.severity = "High";
      break;
    default:
      data.severity = "Unknown";
  }
 
  return {
    data: data,
    warnings: [],
    errors: []
  };
}