“This is a very simple, easy to make, visually effective, and self-contained device intended for both beginners and more advanced DIYers.
Ultrasonic sonar is devices that use sound waves with frequencies higher than the upper audible limit of human hearing (typically above 20 kHz) to measure distances to objects. They work on the principle of sending out a sound wave, and then measuring the time it takes for the sound wave to bounce back after hitting an object. By calculating the time difference between sending and receiving the sound wave, the distance to the object can be determined using the speed of sound in air. In some of my previous videos, you can see several different builds of such a device with special functionalities. All of them display the result on a PC monitor using an additional program written in the Processing application.
This time I will describe to you a simple way how to make an independent Sonar, where the results are displayed on a TFT color display in the form of a radar image, which is why it is often mistakenly called radar instead of sonar.
I got the idea quite by accident from a picture on the internet, and then after a little research I found that project on Github. The original project was made on a 1.8 inch display which is really a very small surface for this purpose. So I reworked the code for a larger 3.2 inch TFT display, where the image is much clearer.
The device is really simple to make and consists of only a few components
- Arduino Nano microcontroller board
- TFT display with a resolution of 240 x 320 pixels and an ILI9341 driver chip
- Ultrasonic sensor type HC-SR04
- small 9G Servo
- and several resistors that serve to shift the display signal from 5V to 3.3V level
The servo and ultrasonic sensor are housed in a separate box, which I used from a previous project, and connected to the main box with flat cables.”