So early in January, the automation of the chicken door started and the Arduino starter kit came in….a good way to start of 2018. It seemed to me that using a microprocessor like the Arduino would be a good place to start, because it could process several factors in the process of the door opening. Like, is it daylight outside? open the door. Is it dark outside? close the door. Is it too cold? maybe best to keep the door closed. What about those pesky geese that don’t go in until well after the chickens have gone to roost. Hmmm.
The starter kit I ordered contains all sorts of components for getting started with learning how a microprocessor works and testing out circuits and programming with it. This kit has enough components to make it a useful starting point. I soon decided to operate remotely, a network connection would need to be made, so I added an Ethernet Shield to the mix. Arduino shields stack onto the top of the Arduino board and connect together quite well.
In the mean time, I started on the mechanical parts of the door. Basically a guillotine style door with a opening of about a foot square for the chickens to get through.
I used the motor from an old battery powered drill. I even used a part of the drill case for the motor mount on the door to hold the motor in place. For the short term, I used a couple of old power supplies, wall warts they are sometimes called, to power the drill motor. Also, since the programming for the Arduino was not coming along as I had hoped, I elected to use a couple of timers and some relays to control the door. The big issue was how much power the drill motor required. After a bit of testing, I found the motor draws about 2.4 amps while lifting the door, and close to the same lowering the door. Initial starting current was a bit over 5 amps. Looking up the motor specs I found the stall amps for the motor at 85 amps. Wow. I did not expect that, so that is the reason for going to the relays, as the typical Arduino motor controllers only support 2 amps max.
Images below show door in place. After only one night, the chickens managed to find a place to drop poop on the timers. So an empty feed bag was used as a cover to prevent additional chicken bombs from landing on the hardware. The upper timer switches the power supply on in the morning, which activates the relay on the left which then causes the motor to turn the threaded rod. The Tee nut on the door follows the thread and raises the door. When the door gets to the open position, a switch is triggered to disconnect the relay and turn off the motor. The timer after a couple of minutes then shuts off the power supply. In the evening, the lower timer turns on, activating the relay on the right which works the same as the one on the left, except that it reverses the polarity of the motor so the motor now rotates the opposite direction causing the door to close. Similar to the door open switch, a door closed switch is also used to turn off the relay when the door reaches the bottom.
The particular Arduino kit that I ordered isn’t currently available on Amazon, but here is one that is pretty similar.
Here is the Timers and Relays I used for the door as it is now.