Using the HC-SR501 PIR Motion Sensor – With Arduino & Raspberry Pi

The HC-SR501 is a Passive Infrared (PIR) motion sensor that is extremely useful. It can be used all by itself or combined with an Arduino or Raspberry Pi

In this article you’ll learn how a PIR sensor works and you’ll build some cool projects using the HC-SR501. You can even make a motion activated camera that will tell you who is stealing your Jelly Beans!

Build a Robot Car with Speed Sensors

Build a Robot Car with Speed Sensors

I’m sure you have seen those inexpensive robot car chassis kits, the ones that come with two 6-volt motors. They are great fun and very useful and they even come with a couple of speed encoder disks (those little black circles full of holes). Problem is, no one tells you how to use them!

Let’s resolve that and build a robot car with speed sensors. Along the way we’ll learn how to use Interrupts, a valuable programming technique.