Pet Door Trigger: Zigbee Button for Pet Flaps

Know when your pet comes back inside. This print turns a THIRDREALITY Zigbee Smart Button into a pet door sensor. The holder sits on the door rail above the flap and a hinged paddle hangs in front of the flap. When your pet pushes through, the flap swings the paddle and an M6 screw on the paddle presses the button. Set it up so only the flap swinging inward clicks the button, and you get a press when your pet comes in but not when they go out. Your Zigbee hub sees a normal button press, so you can trigger any automation you want: a phone notification, a log entry, a light.

Why I made it

My dog goes in and out through the pet door on our storm door. I made this so I get a notification when he comes back in the house, so I know it's time to close the basement door. Mine is on a PetSafe XL flap with a 75 lb dog pushing through it every day.

Features

• Adjustable trigger point. The M6 screw threads into a nut captured inside the paddle. Turn it in or out to set how far the paddle swings before it clicks the button. I set mine so it only triggers when my pet comes back in, not when he goes out.

• Snap-on hinge. The paddle snaps onto pins on the button holder. No extra hardware for the hinge.

• Works with any Zigbee hub that supports the button: Home Assistant (ZHA or Zigbee2MQTT), SmartThings, Hubitat, Aeotec and others.

• Two parts on one plate. The pause for the nut is already set in the 3MF.

What you need

• 1x THIRDREALITY Zigbee Smart Button (the original 1-button, 2x AAA model, not the 3-button ZB2)

• 1x M6 x 30 mm button head screw (M6-1.0)

• 2x M6 hex nuts (one is captured inside the paddle during the print, one goes on the end of the screw)

• A Zigbee hub

• 1 or 2 short screws to fasten the holder to the door

Printing

• This print pauses at layer 35 (7.00 mm). When the printer pauses, drop an M6 hex nut into the hex slot in the paddle, press it flat, and resume. The next layers seal it in.

• Bambu Lab: the pause is built into the 3MF. Printing from the STLs: add a pause at layer 35 (0.2 mm layers with a 0.2 mm first layer). If you change the layer height, pause at the layer that ends at 7.0 mm.

• 0.20 mm layers, 2 walls, 15% infill, PLA. Supports only on the button holder.

• The paddle prints face-down, so the flat side that faces the flap comes out smooth.

Assembly

1. Slide the smart button into the holder with the round button facing out, away from the door.

2. Snap the paddle's hinge onto the pins on the holder.

3. Thread the M6 x 30 mm screw through the paddle into the captured nut.

4. Thread the second M6 nut onto the end of the screw. The nut hits the button evenly. Without it, the bare screw tip can break the button.

5. Turn the screw so the end nut sits just short of the button when the paddle hangs at rest. Then fine-tune it until the flap swinging in clicks the button and the flap swinging out does not.

6. Screw the holder to the door rail directly above the flap, so the paddle hangs in front of the flap. Drive the screws straight through the back of the holder. Don't use tape or Velcro. I tried both and neither held up to the force of the flap swinging into the paddle.

7. Pair the button with your hub and set up the automation (next section).

Tip: test it with your hand on the flap in both directions before trusting it. If it triggers on the way out too, back the screw out a little. If it misses on the way in, turn it in a little.

Home Assistant setup (ZHA)

I use Home Assistant with ZHA. When my dog comes back in, I get a notification on my phone and Home Assistant announces it on my Google Nest speakers. The attached automation does both. In ZHA this button often shows only battery triggers in the automation editor, with no "button pressed" option, so the automation listens for the button's raw zha_event instead.

Needs Home Assistant 2024.10 or newer.

1. Pair the button. Settings > Devices & services > Zigbee Home Automation > Add device, then press the button's reset pin until the light blinks.

2. Create the automation. Settings > Automations & scenes > Create automation > Create new automation. Open the ⋮ menu, choose Edit in YAML, delete what's there, and paste in the code from the attached Pet Door Trigger - Home Assistant automation.txt.

3. Fill in the 4 blanks (listed below), then click Save.

4. Test it. Push the flap inward by hand. You should get the notification and the announcement. Push it outward and nothing should happen. If it fires on the way out, back the screw out a little.

The automation code is attached as a .txt file in the Documentation section below (Pet Door Trigger - Home Assistant automation.txt). Open it, copy everything, and paste it into the YAML editor. Copy from the file, not from this page, so the indentation stays correct.

The 4 blanks to fill in:

• 00:00:00:00:00:00:00:00: your button's IEEE address. Open the button's device page, expand Zigbee info, and copy the IEEE. Keep the quotes.

• notify.mobile_app_your_phone: your phone's notify action. Go to Developer tools > Actions and type notify.mobile_app to find it.

• tts.google_en_com: your text-to-speech entity. This is the default name from the Google Translate text-to-speech integration. Settings > Entities, search tts. to find yours.

• media_player.your_speaker: the speaker to announce on. For Google Nest speakers, add the Google Cast integration and use the speaker's media player entity. For several speakers, list them like [media_player.kitchen_speaker, media_player.living_room_speaker].

Don't want the announcement? Delete the tts.speak block (the 7 lines starting at - action: tts.speak). Change the messages to your pet's name if you like.

What the conditions do:

• 60-second lockout. The flap swings back and forth a few times after your pet comes through. Without the lockout you get several notifications per trip.

• Press, not release. The button reports both the press and the release. This only lets the press through.

Print profile

0.20mm PLA, nut pause at layer 35

This print pauses at layer 35 (7.00 mm). When it pauses, drop an M6 hex nut into the hex slot in the paddle, press it flat, and resume.

• 0.20 mm Standard, Generic PLA

• 2 walls, 15% grid infill

• Tree supports on the button holder only

• Both parts on one plate, Textured PEI plate

• Sliced for: Bambu Lab X1 Carbon

• Plates: 1

• Print time: about 1 h 23 min

• Filament: PLA #FFFFFF (47 g)

• File: the 3MF labeled "print profile" in Model Files

Also on MakerWorld, with one-click print profiles for Bambu Studio: Pet Door Trigger: Zigbee Button for Pet Flaps