How sensors work

Have you ever seen lights turn on automatically when you step into a restroom? Or have you ever wondered how a garage door knows not to close when someone is standing beneath it? What these and countless other electronic devices have in common is a sensor. But how do sensors work? What are they used for? Discover how robotic and electronic sensors can be programmed to work as our five senses do, and learn how they are used to save energy, keep us safe, and sometimes make life a little more convenient!.