IoT Liquid Level Monitoring System

This guide will help you create an IoT-based Liquid Level Monitoring System using Raspberry Pi. The system will monitor the liquid level in tanks or containers and send real-time updates and alerts based on the level detected.

Components Required

• Raspberry Pi (Model 3 or later)
• Ultrasonic distance sensor (e.g., HC-SR04)
• Relay module (for triggering alerts or notifications)
• Connecting wires and breadboard
• Power supply (for Raspberry Pi and sensors)
• Cloud service account (e.g., ThingSpeak, Blynk, or AWS IoT)
• Optional: Buzzer or alarm (for local alerts)

Setting Up the Hardware

Follow these steps to set up the hardware:

1. Connect the Ultrasonic Sensor

   Connect the ultrasonic distance sensor to the Raspberry Pi GPIO pins. This sensor will measure the distance from the liquid surface to the sensor, which can be used to determine the liquid level.

2. Integrate the Relay Module

   Connect the relay module to the Raspberry Pi. The relay can be used to trigger an alarm or send notifications if the liquid level reaches a certain threshold.

3. Power the System

   Ensure that the Raspberry Pi and all connected sensors are properly powered using the appropriate power supplies.

Programming the Raspberry Pi

Write the code to read data from the ultrasonic sensor and send it to the cloud. Below is a basic example using Python:

                import RPi.GPIO as GPIO
                import time
                import requests

                # Configuration
                TRIG_PIN = 23
                ECHO_PIN = 24
                RELAY_PIN = 25
                CLOUD_URL = "https://api.thingspeak.com/update?api_key=YOUR_API_KEY"

                # Setup
                GPIO.setmode(GPIO.BCM)
                GPIO.setup(TRIG_PIN, GPIO.OUT)
                GPIO.setup(ECHO_PIN, GPIO.IN)
                GPIO.setup(RELAY_PIN, GPIO.OUT)

                def get_distance():
                    GPIO.output(TRIG_PIN, True)
                    time.sleep(0.00001)
                    GPIO.output(TRIG_PIN, False)

                    start_time = time.time()
                    stop_time = time.time()

                    while GPIO.input(ECHO_PIN) == 0:
                        start_time = time.time()

                    while GPIO.input(ECHO_PIN) == 1:
                        stop_time = time.time()

                    elapsed_time = stop_time - start_time
                    distance = (elapsed_time * 34300) / 2
                    return distance

                def send_data_to_cloud(distance):
                    response = requests.get(CLOUD_URL + f"&field1={distance}")
                    print(f"Data sent to cloud: {response.status_code}")

                try:
                    while True:
                        distance = get_distance()
                        send_data_to_cloud(distance)
                        if distance < 10:  # Threshold for low level
                            GPIO.output(RELAY_PIN, GPIO.HIGH)
                        else:
                            GPIO.output(RELAY_PIN, GPIO.LOW)
                        time.sleep(60)  # Send data every minute

                except KeyboardInterrupt:
                    GPIO.cleanup()
            

This code reads the distance from the ultrasonic sensor to determine the liquid level and sends this data to the cloud. The relay is triggered if the liquid level falls below a specified threshold.

Setting Up Cloud Integration

To visualize and receive notifications, integrate the system with a cloud service. Configure your cloud service to display liquid level data and set up alerts based on predefined thresholds.

Testing and Calibration

Test the system by simulating different liquid levels and ensuring that the data is accurately captured and sent to the cloud. Adjust sensor calibration and code parameters as needed for reliable performance.