Dear friends welcome to another video. Today we learn how to use this
Ultrasonic  sensor with Arduino and build
this simple distance meter with a Nokia LCD display.
Let's start! In this project we use an
Arduino Uno,  a Nokia 5110 LCD display and
the HC SR04 ultrasonic sensor.
As you can see in the display, we see the distance that the sensor
measure. If I place my hand close to the sensor,
the display shows the distance of my hand
from the sensor. If I remove it, it shows the distance from the
opposite wall. This ultrasonic sensor is a quite
interesting device. There ultrasonic module detects
the distance of the closest object in front of the sensor.
The maximun distance in which it detects an object
is 4 meters. It works by sending out
a burst of ultrasound and listening for the
echo when it bounces off of an object. The module sends
a short pulse through pin Trig to trigger the detection.
Then, listens for a pulse in the pin Echo.
The duration of the second pulse is equal to the time
taken by the ultrasound to travel to the object and back to the sensor.
Using the speed of sound this time can be
converted to distance. Now let's see how to build this project, it is very simple!
The sensor
has only 4 pins to connect. Vcc
Trigger, Echo and Ground. Let's connect first
Vcc and Ground. Vcc goes to
Arduino 5V. Ground goes to Arduino Ground,
Trigger goes to digital pin 7
and Echo goes to digital pin 6. Now let's connect the Nokia 5110
LCD display. I have now connected the Nokia 5110
LCD display. Please check our previous tutorial on how to connect a Nokia
5110 LCD display in your Arduino project.
Now if I power on
Arduino, let's see if it is working, OK it is working fine!
As you can see it measures distance
and it updates the distance if I move my
hand close to it. OK perfect!
Now let's go to the computer and see the software side
of the project. I have prepared two
programs for you
The first one is really simple. It does not use a Nokia 5110
LCD display in case you don't have one. It does not need any
libraries at all. All it does is to display the distance it
measures from the sensor to the serial monitor. Let's see.
OK, that's the distance in centimeters. It is
updated every 50 milliseconds.
the second program uses the Nokia 5110
LCD display, so we need a library for the display.
Check out the Nokia 5110 LCD display tutorials
I have prepared in order to see how to
use to display
and  how to load graphics on it. The code is very simple.
We draw the UI bitmap and then we
measure the distance from the sensor.
We convert the value we get to a string and then
we display that value.
As always you can find the code of the project in the description of the video.
That's todays video. An interesting and
very easy build project. The distance sensor will be useful to our future projects as well
like the autonomous robot. So stay tuned!
Thanks for watching the video please press the like button if you like the project
and subscribe to our channel
in order to watch our future videos.
thank you very much
and see you next week!
