Raspberry Pi - Ultrasonic Sensor - LCD

This tutorial instructs you how to use Raspberry Pi to obtain the distance from an ultrasonic sensor and display it on an LCD I2C.

Hardware Preparation

1	×	Raspberry Pi 4 Model B
1	×	LCD I2C
1	×	Ultrasonic Sensor
1	×	Jumper Wires
1	×	(Optional) Screw Terminal Block Shield for Raspberry Pi
1	×	(Optional) USB-C Power Cable with On/Off Switch for Raspberry Pi 4B
1	×	(Optional) Plastic Case and Cooling Fan for Raspberry Pi 4B
1	×	(Optional) HDMI Touch Screen Monitor for Raspberry Pi

Or you can buy the following sensor kits:

1	×	DIYables Sensor Kit (30 sensors/displays)
1	×	DIYables Sensor Kit (18 sensors/displays)

Disclosure: Some of the links provided in this section are Amazon affiliate links. We may receive a commission for any purchases made through these links at no additional cost to you.
Additionally, some of these links are for products from our own brand, DIYables.

Overview of Ultrasonic Sensor and LCD

If you are unfamiliar with ultrasonic sensor and LCD (including pinout, how it works, and how to program), the following tutorials can help you learn:

Wiring Diagram

This image is created using Fritzing. Click to enlarge image

To simplify and organize your wiring setup, we recommend using a Screw Terminal Block Shield for Raspberry Pi. This shield ensures more secure and manageable connections, as shown below:

Raspberry Pi Screw Terminal Block Shield

Raspberry Pi Code

Detailed Instructions

Make sure you have Raspbian or any other Raspberry Pi compatible operating system installed on your Pi.
Make sure your Raspberry Pi is connected to the same local network as your PC.
Make sure your Raspberry Pi is connected to the internet if you need to install some libraries.
If this is the first time you use Raspberry Pi, See how to set up the Raspberry Pi
Connect your PC to the Raspberry Pi via SSH using the built-in SSH client on Linux and macOS or PuTTY on Windows. See to how connect your PC to Raspberry Pi via SSH.
Make sure you have the RPi.GPIO library installed. If not, install it using the following command:

sudo apt-get update sudo apt-get install python3-rpi.gpio

Prior to utilizing the LCD I2C with a Raspberry Pi, we need to enable I2C interface on Raspberry Pi. See How to enable I2C interface on Raspberry Pi
Install the LCD I2C library by running the following command:

pip install lcddriver

Create a Python script file ultrasonic_lcd.py and add the following code:

""" This Raspberry Pi code was developed by newbiely.com This Raspberry Pi code is made available for public use without any restriction For comprehensive instructions and wiring diagrams, please visit: https://newbiely.com/tutorials/raspberry-pi/raspberry-pi-ultrasonic-sensor-lcd """ from gpiozero import DistanceSensor from lcddriver import lcd from time import sleep # GPIO pins for ultrasonic sensor TRIGGER_PIN = 16 ECHO_PIN = 20 # I2C address 0x27, 16 columns, 2 rows LCD = lcd() # Create ultrasonic sensor instance ultrasonic_sensor = DistanceSensor(trigger=TRIGGER_PIN, echo=ECHO_PIN) def display_distance(distance): LCD.lcd_clear() LCD.lcd_display_string(f"Distance: {distance:.2f} m", 1) try: while True: distance = ultrasonic_sensor.distance display_distance(distance) sleep(0.5) # Sleep for 500 milliseconds except KeyboardInterrupt: pass finally: LCD.lcd_clear()

Save the file and run the Python script by executing the following command in the terminal:

python3 ultrasonic_lcd.py

The script runs in an infinite loop continuously until you press Ctrl + C in the terminal.

Code Explanation

Check out the line-by-line explanation contained in the comments of the source code!

※ NOTE THAT:

If the LCD is not displaying anything, take a look at Troubleshooting on LCD I2C.
The code provided is for educational purposes. The ultrasonic sensor is very sensitive to noise, so if you plan to use it in a real-world application, you should filter the noise from the ultrasonic sensor. See how to filter noise for ultrasonic sensor for more information.

Video Tutorial

Learn More

※ OUR MESSAGES

As freelancers, We are AVAILABLE for HIRE. See how to outsource your project to us
Please feel free to share the link of this tutorial. However, Please do not use our content on any other websites. We invested a lot of effort and time to create the content, please respect our work!