I wanted to use an IKEA Motion Sensor (Trådfri) for motion detection. First I tried to find a way to
get hold of the sensoring through the procotol using Coap-client etc. But no luck getting the triggered values out through the API.
So I found this guide Hack: IKEA Trådfri Motion Sensor for presence control.
But I wanted it to be integrated without the need to have multiple separated devices. Hence, I assembled them into one unit.
The motion sensor now includes a “light” that is controlled by the sensor itself. The power is taken from
the batteries included in the motion sensor itself so no external power source is required. This will lower
the max battery capacity a bit. But they are estimated to last 2 years, so let’s split that into half for at least
one of the batteries that I use as the power source.
Materials:
- GU10 400lm Trådfri lamp (https://www.ikea.com/se/sv/p/tradfri-led-ljuskaella-gu10-400-lumen-tradloes-dimbar-varmvit-80365270/)
- Bright Green LED (2.9 - 3.6V, no need for resistor)
- IKEA Motion Sensor (Trådlös rörelsesensor) (https://www.ikea.com/se/sv/p/tradfri-tradloes-roerelsesensor-vit-70429913/)
Total price: 169 SEK (excl. the green diode)
Once the Zigbee board is desoldererd it can be fixed into the original motion sensor case. I also created a little hole for the LED so that I can see when it’s triggered. When it’s in place it’s easy to pair it with the sensor. Just pair as you do as usual, but the 2cm proximity is easily covered 
Here is a little video of it being used:
Some images of the project…
Final result
As you can see, there is not much seen after the mod. Just a little white cable sticking out:
Some images during the process:
I’m using the same configuration as for the guide (Hack: IKEA Trådfri Motion Sensor for presence control). Using it as a binary sensor, but I have this automation as well:
automation.yaml:
- id: alarmhouse
alias: "alarm motion detector"
initial_state: 'on'
trigger:
- platform: state
entity_id: binary_sensor.motion_house
from: 'off'
to: 'on'
condition:
- condition: state
entity_id: alarm_control_panel.ha_alarm
state: armed_away
action:
- service: tts.google_translate_say
data:
message: "Motion detection"
configuration.yaml:
- platform: template
sensors:
motion_house:
friendly_name: "Motion Sensor House"
entity_id: light.sensorlampa
value_template: '{{ is_state("light.sensorlampa", "on") }}'
device_class: motion
