Smart Irrigation System

This project implements a Smart Irrigation System using an ESP32 microcontroller, soil moisture sensor, PIR sensor, relay module, and a buzzer. The system monitors soil moisture levels and detects motion to control irrigation and provide Alerts.

Components Used

• ESP32 microcontroller
• Soil Moisture Sensor
• PIR Sensor
• Relay Module (SRD-05VDC-SL-C)
• Buzzer
• Jumper Wires
• Breadboard

Features

• Soil Moisture Monitoring: Continuously monitors soil moisture levels and activates the relay then the built in Led is on of the ESP-32 and to start irrigation when moisture falls below a predefined threshold 100. you can change the threshold according your Requirement.
• Motion Detection: Detects motion using a PIR sensor and activates a buzzer to provide an alert.
• Configurable Threshold: The soil moisture threshold for triggering irrigation can be adjusted based on sensor Calibration.

Circuit Diagram

Connections

1. Soil Moisture Sensor:

   • VCC to 3.3V of ESP32
   • GND to GND of ESP32
   • Data to GPIO34 of ESP32 (analog pin)

2. PIR Sensor:

   • VCC to 3.3V of ESP32
   • GND to GND of ESP32
   • Output to GPIO35 of ESP32 (digital pin)

3. Relay Module:

   • VCC to 3.3V of ESP32
   • GND to GND of ESP32
   • IN to GPIO2 of ESP32

4. Buzzer:

   • One pin to GPIO4 of ESP32
   • Other pin to GND of ESP32

Installation and Setup

1. Install ESP-IDF: Follow the official ESP-IDF installation guide to set up the development environment.

2. Clone the Repository:

   git clone https://github.com/your-username/smart-irrigation-esp32.git
   cd smart-irrigation-esp32

3. Configure the Project:

   idf.py menuconfig

4. Build the Project:

   idf.py build

5. Flash the Firmware:

   idf.py -p /dev/ttyUSB0 flash monitor

Code Explanation

Main Application

The main application function initializes the ADC for the soil moisture sensor, configures the GPIOs for the PIR sensor, relay, and buzzer, and enters a loop to continuously monitor the sensors and control the relay and buzzer accordingly.

/**
 * @file smart_irrigation.c
 * @brief Smart Irrigation System with Soil Moisture Sensor and PIR Sensor
 *
 * This program monitors soil moisture levels and detects motion using a PIR sensor.
 * It controls a relay for irrigation and activates a buzzer when motion is detected.
 */

#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/gpio.h"
#include "driver/adc.h"
#include "esp_log.h"

// GPIO pin definitions
#define SOIL_SENSOR_PIN    ADC1_CHANNEL_6 ///< ADC channel for soil moisture sensor (GPIO34)
#define PIR_SENSOR_PIN     GPIO_NUM_35    ///< GPIO pin for PIR sensor
#define RELAY_PIN          GPIO_NUM_2     ///< GPIO pin for relay module
#define BUZZER_PIN         GPIO_NUM_4     ///< GPIO pin for buzzer

// Threshold for soil moisture level
#define MOISTURE_THRESHOLD 100 ///< Soil moisture threshold for triggering irrigation

static const char *TAG = "SmartIrrigation"; ///< Tag for logging

/**
 * @brief Main application function
 *
 * This function initializes the ADC for the soil moisture sensor, configures the GPIOs
 * for the PIR sensor, relay, and buzzer, and enters a loop to continuously monitor
 * the sensors and control the relay and buzzer accordingly.
 */
void app_main(void) {
    // Initialize ADC for soil moisture sensor
    adc1_config_width(ADC_WIDTH_BIT_12);
    adc1_config_channel_atten(SOIL_SENSOR_PIN, ADC_ATTEN_DB_0);

    // Configure GPIO for PIR sensor
    gpio_config_t pir_config = {
        .pin_bit_mask = (1ULL << PIR_SENSOR_PIN),
        .mode = GPIO_MODE_INPUT,
        .pull_up_en = GPIO_PULLUP_ENABLE,
        .pull_down_en = GPIO_PULLDOWN_DISABLE,
        .intr_type = GPIO_INTR_DISABLE
    };
    gpio_config(&pir_config);

    // Configure GPIO for relay and buzzer
    gpio_set_direction(RELAY_PIN, GPIO_MODE_OUTPUT);
    gpio_set_direction(BUZZER_PIN, GPIO_MODE_OUTPUT);

    while (1) {
        // Read soil moisture value
        int soil_moisture_value = adc1_get_raw(SOIL_SENSOR_PIN);
        ESP_LOGI(TAG, "Soil Moisture: %d", soil_moisture_value);

        // Read PIR sensor value
        int pir_value = gpio_get_level(PIR_SENSOR_PIN);

        // Control relay based on soil moisture
        if (soil_moisture_value < MOISTURE_THRESHOLD) {
            gpio_set_level(RELAY_PIN, 1); // Activate relay
            ESP_LOGI(TAG, "Soil is dry! Activating relay...");
        } else {
            gpio_set_level(RELAY_PIN, 0); // Deactivate relay
            ESP_LOGI(TAG, "Soil moisture is adequate.");
        }

        // Control buzzer based on PIR sensor
        if (pir_value == 1) {
            ESP_LOGI(TAG, "Motion detected! Activating buzzer...");
            gpio_set_level(BUZZER_PIN, 1); // Turn on buzzer
            vTaskDelay(pdMS_TO_TICKS(5000)); // Buzzer on for 5 seconds
            gpio_set_level(BUZZER_PIN, 0); // Turn off buzzer
        }

        vTaskDelay(pdMS_TO_TICKS(2000)); // Delay for 2 seconds before the next reading
    }
}