DIY Invisible Home Automation

If your smart home system responds to your voice requests from anywhere in your house — to turn on lights, play music, or check your calendar — you are off to a good start. But smart homes can be far more advanced than this. The real fun begins when automation is introduced into the system — maybe a light turns on when you walk into the room, or a speaker plays a summary of the day’s schedule when you wake up.

To introduce automation of this sort, more information is needed. In particular, the system needs to be aware of where you are at all times. This is commonly achieved by installing door sensors, as they are inexpensive and easy to set up — even if they do not give especially fine-grained information.

This is the approach taken by Dillan Stock. He uses a few of these sensors to turn on dim lights when he enters his child’s bedroom, or when opening the patio door. What he really wants, however, is to install these sensors on every door in his home. But what he really doesn’t want is to have a big, ugly sensor at the top of all of the doors in his home.

Stock has been working with the Aqara T1 door sensors because they are cheap, communicate via Zigbee, and the batteries last a very long time. But while they are excellent from a technical perspective, they are too large. Stock previously worked with the Aeotec Recessed Door Sensor 7, which doesn’t work very well and is expensive — but this one fits into a small hole drilled into the top of the door that makes it disappear.

This gave Stock the idea of stuffing the Aqara T1 hardware into a redesigned case that mimics the look of the Aeotec sensor. To make that possible, he disassembled the Aqara device and measured the circuit board. A 3D model was then developed to fit it before it was 3D printed. Another small, circular case was also printed for a magnet, which is installed in the door frame above the sensor so that it can tell when the door is open using its reed switch.

With the new device assembled, Stock only needed to drill small holes into each door and frame to pop the sensor and magnet in place. Now he can easily outfit his entire smart home with door sensors that are virtually invisible. Be sure to check out the video below for all of the details.