Chicken Door Automation for Omlet

Thank you for supporting me!

This is another free 3D model made available for you. I love sharing my models, but designing, testing, polishing, uploading and maintaining them is a lot of work. In case you enjoy this model, please leave a small Donation or Buy me a Coffee. Thank you!

Design

This is a chicken door automation designed for our two Eglu Cube and one Eglu Go chicken houses. Operated by an ESP8266 microprocessor featuring a RESTless API, it can be easily integrated into a home automation system.

Features:

• can be added (almost) without modifying the chicken house
• controls a motor to open / close the door
• controls a light to attract chickens to move in
• supports several commands using a RESTfull API:
  • door status
  • open door
  • close door
  • light status
  • turn light on
  • turn light off
• button to open and close the door manually
• displays door status using two LEDs

How we use it:

Doors are opened automatically at sun rise or 7am - whatever comes last. Light is turned on at sun set. Door closing is operated from remote - but manually. This is because our chickens have not completed their learning curve to move in completely yet. To not wrap the chickens, we watch them using an IP cam and close it from remote by issuing a HTTP request (integrated into our home automation) . Once the door is closed, the light is turned off automatically.

Possible improvements:

• detect when a chicken is wrapped by the closing door and open it again
• add gaskets
• protect against self destruction

Printing:

Use 0.4mm nozzle, 0.2mm layer height, and PETG filament. Most parts do not need support and can be printed using the model orientation. BaseTopMotor and the Lid need “support on built plate only”. MotorMount needs to be rotated by 90 degree on the closed end (the one with the screw holes). In addition, it needs “support on built plate only”.

Initially, we used a rounded Lid.stl model. As it has been hard to print (tons of support when printed as shown and ugly rounding when printed upside down), it has been replaced by a new version using a chamfer instead of the rounding. It improves quality and speed a lot.

Parts required (see photo on red table):

• ESP8266 D1 Mini
• red and green LEDs, two matching resistors (330 Ohm)
• button for manual operation (for 12mm hole)
• 12 V DC gear motor
• 230V / 12V DC transformer
• Motor Drive Controller Board Module L298 N H Bridge DC
• brass worm shaft set 6mm
• flange coupling 6mm
• some 12V LED light (1W or smaller)
• a custom 6mm stainless steel axle
• 2 reed contacts, 1 matching magnet
• or 2 micro switches plus M3 screws at length 12mm
• the usual small electronic parts and cables
• M3 screws at lengths 8mm, 10mm, 20mm
• 2 component glue of your choice
• grease

Building instructions:

Assemble Base

• print all parts
• glue MotorMount into BaseTopMotor
• once dried, add a 20mm M3 screw to join the two parts even better
• create stainless steel axle according to sketch and photos
• push motor into mount and fix it using 6 M3 8mm screws
• add worm to motor axis and tighten its screw
• solder 2 reed contacts to thin cables, test functionality using a magnet
• glue reeds and cables into Base
• place the magnet into one(!) of ZahnradKnebel1 or ZahnradKnebel2, keep the other hole empty(!)
• place flange coupling into ZahnradMotor and fix it using 3 M3 8mm screws
• place ZahnradMotor into Base, add lots of grease as this will make the difference in smoothness of operation
• push axle into flange and make sure it is aligned to Base's bottom,
• tighten 2 screws in flange coupling
• place motor with BaseTopMotor onto ZahnradMotor, add lots of grease again
• fix it using 4 M3 10mm screws
• make sure ZahnradMotor can turn freely, add 4 spacers otherwise
• push worm gear on axis so the motor is connected to ZahnradMotor
• connect ZahnradKnebel1 / ZahnradKnebel2 and place them into Base
• place BaseTopKnebel on top of ZahnradKnebel1 / ZahnradKnebel2, add lots of grease again
• fix it using 4 M3 10mm screws

Micro switch alternative

Reed contacts are not perfect to detect the end of movement: they need to be calibrated because the point of switching varies by orientation and magnet strength; furthermore, when near a magnet for a long time, they may get magnetized and stop working. So I have added changed versions of ZahnradKnebel1, ZahnradKnebel2, and BaseTopKnebel. In addition to reed operation, they allow mounting two micro switches. When using these, please print ContactHolderOpened and ContactHolderClosed in addition. Use two M3x12 screws to mount them. See the parts list for the switch specs.

Electronics

Not detailed here. 

See photos for the circuit diagram. Everything except the transformer will go into the base. So the power supply cable going into Base is 12V DC. In case you add a light (recommended), its cable is going through the remaining hole in the Base floor.

The ESP8266 program is provided on GitHub. See instructions available there.

I recommend to use sockets for the ESP8266. This allows you to remove it and test / flash it at your desk instead of the chicken stable. ;-)

I have added two mounts for the ESP and the motor driver. They match the part I have used (see links above). You may need to design your own in case your choose different boards. Both mounts are added to the Base (see photos) using double-sided adhesive tape.

Calibration and assembly to chicken house

Please read through this section carefully. The system can self-destruct itself in case you do not follow this instructions.

Pre-testing

• do not assemble with the twistable handle of the Eglu yet, initial calibration should be done on your desk!
• with Base assembled, Electronics finished and ESP8266 flashed, connect to power
• in case the magnet in ZahnradKnebel is positioned above the open or close reed contact, you will see one LED on and one off; in case the red one is on, the system in “door opened” position; in case the green one is on, the system is in “door closed” position
• in case the magnet is somewhere else (not closing one of the reed contacts), both LEDs will blink, the motor will turn until ZahnradKnebel is in open position
• in case the motor turns but doesn't stop, there is a problem with the open contact not being closed
• to make sure things work once the system is attached to the chicken house, press the button; this should make ZahnradKnebel move between close and open positions
• check motor polarity: opening the door needs to turn ZahnradKnebel counter clockwise (top down view), closing needs to turn clockwise; switch polarity in case it is the opposite
• finish by moving the system to “open door” position

Real life testing

• bring the system to your chicken house and re-check the turning of ZahnradKnebel and the Eglu's twistable handle is sound
• remove the four screws of BaseTopKnebel and remove it
• remove the ZahnradKnebel1 and ZahnradKnebel2 but memorize their exact position
• place the base in the chicken house so you can pull up the twistable handle through the big hole
• put grease into the housing of ZahnradKnebel1 and ZahnradKnebel2 - the handle will push these two down later; the grease helps to reduce friction
• make sure the twistable handle is in “open door” position
• pull the handle fully up and place ZahnradKnebel1 and ZahnradKnebel2 under the handle; depending on the factory side handle assembly, this can be difficult
• let the handle go down so it sits between ZahnradKnebel1 and ZahnradKnebel
• recheck everything
• hold the base with a hand and turn on power; the red light should go on as the door is in open position
• while still holding the base, press the button to check closing / opening the door
• find the base position you have the least friction / noise
• screw the base onto the chicken house using four screws going through the Base's floor
• as the housing is rounded, it makes sense to add  some spacers so the Base's floor is perpendicular to the door axle
• re-test operation now that everything is fixed
• connect and install the optional lightning by drilling a hole through the chicken house's roof (and  through the remaining hole in the Base's floor

Calibration

• both the open and close reed contacts will be triggered before the door is fully opened or closed
• adjust CLOSE_RUNOVER_MILLIS and OPEN_RUNOVER_MILLIS in the sketch to add an amount of milliseconds the motor should continue to turn after the contact is closed already; in case the values are too high, things may break; in case  the values are too low, the door will not open / close completely; start with zero for both and increase by 100ms between testing; our two devices have 500 to 800ms set;

Final tests

• as the system can be remote controlled, try these REST APIs using a browser:
  • http://<IP>/opendoor
  • http://<IP>/closedoor
  • http://<IP>/status
  • http://<IP>/illuminate
  • http://<IP>/illuminationoff
  • http://<IP>/statusillumination

Do not forget to put the lid on the system. Protect the system against rain.

Congratulations!