Infrared Obstacle Avoidance sensors are cheap, small sensors often used in robots, and Arduino project to detect objects near the sensor.
The Infrared sensors work by sending an infrared light with some frequency, and then detecting if some of the light has reflected back to the sensor. The most common ones have a digital output indicating if object has been detected. Many of them have the option to be enabled or disabled.
In this Instructable, I will show you how easy it is to connect and use such sensor with Arduino.
Some of the sensors have a brief false detection when they are enabled. In the Instructable, I will also show you how you can suppress this false detection withVisuino.