Plant Monitoring System with Soil Moisture and Light Sensors via MQTT Communication

11.12.2024 - Engine: Gemini

Setting Up a Plant Monitoring System with Soil Moisture and Light Sensors Using MQTT Communication

Components

• Microcontroller (e.g., Arduino Uno, ESP32)
• Soil moisture sensor (e.g., YL-69)
• Light sensor (e.g., BH1750)
• MQTT broker (e.g., Mosquitto)
• MQTT client (e.g., MQTT library for Arduino)

Steps

1. Hardware Connection:

• Connect the soil moisture sensor to the microcontroller's analog pins.
• Connect the light sensor to the microcontroller's I2C bus.

2. Software Configuration:

• Install the MQTT library on the microcontroller.
• Establish a connection to the MQTT broker.
• Define MQTT topics for publishing sensor readings.

3. Soil Sensor Measurement:

• Read the analog value from the soil moisture sensor.
• Convert the value to a soil moisture measurement.

4. Light Sensor Measurement:

• Read the lux value from the light sensor over I2C.

5. MQTT Publishing:

• Publish soil moisture and light sensor readings to MQTT topics with appropriate message payloads.

6. MQTT Subscription:

• Subscribe to the MQTT topics on another device or a dashboard to receive sensor readings in real time.

Sample Code:

// Arduino code for plant monitoring using MQTT

#include <MQTT.h>

const char* ssid = "SSID";
const char* password = "Password";
const char* mqtt_server = "mqtt_server";
const int mqtt_port = 1883;
const char* mqtt_topic_moisture = "moisture";
const char* mqtt_topic_light = "light";

MQTTClient client(256);

void setup() {
  Serial.begin(115200);

  // Connect to Wi-Fi
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
  }

  // Connect to the MQTT broker
  client.begin(mqtt_server, mqtt_port, client);

  // Subscribe to MQTT topics
  client.subscribe(mqtt_topic_moisture);
  client.subscribe(mqtt_topic_light);
}

void loop() {
  // Read sensor values
  int moisture_value = analogRead(A0);
  float light_value = bh1750.readLightLevel();

  // Publish the values
  client.publish(mqtt_topic_moisture, String(moisture_value).c_str());
  client.publish(mqtt_topic_light, String(light_value).c_str());

  delay(1000);
}