Automating Capacitive Buttons with a Modified Switchbot

I’ve had a heater in my home office this winter and I’ve wished it could turn on/off automatically based on whether or not I was in the room. A smart outlet wouldn’t work for this because the heater has a manual switch. My next thought was to use my Switchbot smart button pusher, but even this wouldn’t work because the heater uses capacitive buttons.

After doing some digging and experimenting, I discovered a great way to allow the Switchbot to control a capacitive button. Here is my modified Switchbot in action:

Modifying the Switchbot

First, you need to get some metallic tape. I used some extra aluminum foil tape that I had from a previous HVAC project but any kind of metallic tape should work.

Then pop the lid off the Switchbot and remove the battery. Then cut a very thin piece of metallic tape the exact width of the Switchbot “finger” (about 5mm in width). Then attach one end of the metallic tape to the outside of the switch bot finger and the other end to the negative terminal of the battery.

Make sure to leave the paper backing on the tape everywhere except for the two ends so it doesn’t stick to itself.

Also, you should leave enough slack in the metallic tape to allow the “finger” to fully rotate out without causing stress on the tape. It might take a few tries to get the tape exactly the right length.

Then carefully put the battery back in, reattach the lid and you should now be able to fully control capactive buttons with your Switchbot.

Conclusion

This is a pretty simple modification that only takes a few minutes and works really well. I highly recommend doing it if you need your Switchbot to control something with a capacitive button.

Also, if you do have Switchbot devices I highly recommend the Switchbot MQTT BLE ESP32 project. It’s super easy to flash onto a cheap ESP32 microcontroller and it allows all of your Switchbot devices to be controlled via MQTT with home assistant. My new home office setup is able to detect when I’m in the room and run the appropriate automation which now includes turning on the heater if the temperature is cold enough.