In-Bed Presence Detector (SmartThings + Z-wave pressure mat)
Step 1: What you'll need
To build this Z-wave connected pressure mat, you'll need:
1. A Z-wave open/close sensor with leads allowing you to connect your own switch (The author used an Ecolink DWZWAVE2-ECO).
2. An easily modifiable pressure mat (The author used an Ideal Security SK630 Pressure Mat.)
Many of these pressure mats are weather-proof. It is definitely a good idea to get a waterproof may if you are planning to use this in the bed of a child, elderly loved one, or someone with complex medical needs.
Step 2: Test the individual components
Before you modify the pressure mat, it's good to make sure it works as expected. Try connecting the cord of the mat to the alarm and testing that you hear the chime.
This way, if it seems like the mat is broken, you can still send it back. (In subsequent steps, we'll modify the mat, which might make a return more difficult.)
Similarly, now would be a good time to test your open/close sensor to make sure it is working. Connect it to your hub of choice. (The author used Samsung SmartThings.)
Step 3: Expose pressure mat bare wires
Cut the plug off the end of the pressure mat cord, removing some insulation in order to expose sufficient wire to connect the open/close sensor.
Step 4: Connect the pressure mat to the open/close sensor
Open up the open/close sensor. As long as you bought an open/close sensor which allows you to hook in your own switch, you should see a space to connect the bare wires, similar to what is shown. Connect the wires from the pressure mat. At this point, you should be able to test that the mat is properly connected to the open/close sensor by putting pressure on it. (The sensor should indicate via LED light that it is opening/closing.)
Step 5: Test the final result
Time to test your Z-wave connected pressure mat! You can see in the video that when I step on the mat, the Samsung SmartThings app indicates that the sensor is reporting closed. When I lift my foot, it reports open again.
The author used this device in the bed of his son, who has medically complex needs. It was used in the following scenarios:
· turning off our home stereo system automatically when my son goes to bed
· blink lights in another room if my son is in bed and his heart rate monitor (see https://github.com/yahnatan/pulseox) indicates that he might need assistance