How an Arduino Ultrasonic Sensor Works

In this electronics tutorial we go over how an HC-SR04 ultrasonic distance sensor works with the arduino to determine a distance to an object.

The basic idea is that it send out a sound wave that is reflected by object. Then my measuring the time for the wave to make the trip you can determine distance. We have used the sensors to control the LittleArm arduino robot arm.

For more information visit http://www.littlearmrobot.com/