My parents wanted to automate the door to their chicken coop. I saved them money by building a cheap electronic mechanism from scratch.

Backstory

My parents raise chickens in their backyard and wanted a way to automate opening and closing the door to their chicken coop. All of the products I found on Amazon Prime (door + controller) were quite expensive—and overpriced in my opinion—so I decided to see whether I could reverse engineer the functionality at a cheaper price point.



Challenges

This project had several requirements and design constraints that made things tricky. The biggest one was the budget. Since our budget was $100 and the door we planned on buying was $50 online, I only had $50 for the automation/door controller for this build. Here is what I needed to figure out:



Needs to be battery operated and last for at least two weeks (14 days)

Needs to open in the morning and close in the evening, after all birds have entered the coop

Needs to cost $50 or less to assemble

Needs to be weatherproof

If price weren’t a constraint, I immediately would have chosen a cellular IoT board like the Particle Electron or Boron ($50). Connectivity to the cloud provides several advantages:



Remote/manual control of the door via the cloud

Internet connectivity provides clock times that are always in sync Clock crystals in microcontrollers tend to be inaccurate for long-term use cases RTC modules can accomplish this but require an external coin cell battery and cost $15 (a significant chunk of my budget)

Ability to create a user interface on web/mobile Gives some transparency to the tech, which would otherwise be a black box to my parents



Time to Build!

However, I also needed a motor to move the door up and down. I decided to use a sensor-based approach to opening and closing the coop door. I ended up with a pretty simple parts list:



Arduino UNO Low-cost programmable microcontroller with barrel-jack access for power

AA battery pack to male barrel-jack Powers the Arduino

10K resistor, wires, photoresistor For a voltage divider circuit to serve as a daytime/night-time sensor

ULN2003 Stepper Motor Plug & play, as far as motors go, these work with the Arduino stepper motor libraries

Titan Incubators Chicken Coop Door The door

Small salad container from the local grocery store (free) Weatherproof container for electronics

from the local grocery store (free)

Once I had all the parts ordered, it was just a matter of putting everything together. Check out the video at the beginning of this post to see me assembling this thrifty automatic chicken coop door!