The HC-SR04 Ultrasonic Range Finder is an economical sensor that provides 2 to 400 cm of non-contact measurement functionality with a ranging accuracy that can reach up to 3 mm. Each HC-SR04 module includes an ultrasonic transmitter, a receiver and a control circuit.
There are only four pins that you need to worry about on the HC-SR04: VCC (Power), Trig (Trigger), Echo (Receive), and GND (Ground). You will find this sensor very easy to set up and to use for your next range-finding project!
Easily plugged with a Arduino Uno using the Newping library. I am a a newbie with Arduino and I noticed that sometimes I received a distance à 0 even if there's an object in front of the sensor. I don't know why. I have to investigate this issue. Maybe there's something wrong in my code.
