Disclaimer: I’m an engineer, not a pro film maker. Be advised.

Disclaimer: I’m an engineer, not a pro film maker. Be advised.

 

Ever get that feeling someone is sneaking up on you? Tired of looking over your shoulder in your cube? This project solves that problem in a quiet, simple way – with a motion sensor and some lights.

  

The project by sections:

A Passive Infrared Sensor (PIR Sensor) is some old technology. It dates back to Herbert Berman in 1970!

 

Today the ability to add complete PIR sensor systems to any project is easier and cheaper than ever. It might be old, but it can be used for more than just a nighttime garage light. Just take a look at my Monster Motion Sensor project and see how.

 

I wanted to make a super simple version of a motion detection alert system using the same PIR sensor from the Monster Motion project.

 

The requirements were fairly simple:

- Detect motion, even in a bright room.

- Light up a series of addressable LEDs.

- Ability to switch between modes – cascading lights and a nightlight mode.

 

BOM:

1x Arduino Uno

1x PIR Sensor

A reel of addressable LEDs

Lots and lots of jumper wires

 

Tools you’ll need:

Soldering iron & solder

 

Wiring pointers:

To place the PIR sensor in a place that was optimal, I had to extend its leads. I used several 12” jumper wire extensions on each lead. Several end-to-end. It isn’t the best way to go about it, but it worked.

You can power the whole thing off of USB power, or a single power supply. However, you will overdrive the onboard regulator. It’ll get pretty hot. I recommend having a separate power supply for the LEDs, beyond the one on the Arduino.

 

Schematic and design:

 

Here is the pin-out for the PIR sensor I used. There was no stencil indicating what was what. So, here it is.

 

Code:

See attached to this post

 

Difficulties:

- It’s pretty simple.

 

Other uses of the system:

- It senses motion and turns something on. This can be adapted to turn on anything.

 

If I had more money/time:

- I would have liked to narrow the sensing area of the PIR sensor. I later thought of placing it inside of a tube. After it acclimated to its new tube-house, it would have a far narrower field of view.

 

Oddities and observations:

- The power regulator did get pretty how until I used a separate power supply for the LEDs. 

 

C

http://twitter.com/Cabe_Atwell