In this talk I'll show you how I created a raspberry pi-powered chicken door using only Free Software. You can use this knowledge to get inspired to create your own automated hardware+software systems. I'll go over these features:

• hardware interleave gravity lock mechanism
• instant-read photoresistor poll door actuation trigger
• photoresistor signal analog to digital conversion
• worm gear 12V DC motor controlled via L9110 motor driver chip
• dual hall-effect magnetic door position sensors
• fallback door status mitigating magnetic sensor failure
• night-vision wide-angle camera with motion-triggered video capture
• C + bash + python polyglot control code with standardized output convention
• offline operation with 2.4Ghz wifi for monitoring and maintenance

I'm a hardware beginner, so this is a beginner talk in terms of hardware. I know just enough about hardware to ask someone smarter how to not make everything start smoking.

I've been writing software for about 20 years, so I want to get into some detail about the software.

This talk isn't about carpentry--you'll have to ask my wife about that.

• slides
• video
• source code for door controller
• follow-up blog post