XeThru doorbell

Discussion in 'Presence Sensor' started by Marius Lind Volstad, Sep 13, 2015.

  1. Hi,

    Just wanted to share what I'm currently using my XeThru sensor for.
    A few weeks back I found the transmitter of my wireless doorbell to have a flat battery. I didn't have a fresh battery readily available and constantly forgot to pick one up, so I was without a doorbell for quite some time. Then it hit me: I have a wall-penetrating XeThru radar at my disposal.

    I dug up a Raspberry Pi and connected the XeThru sensor to the USB port. Using some Python code (attached) I managed to get a presence/non-presence event transmitted over WiFi to my home automation server running OpenHAB. My OpenHAB setup is configured to deliver a Pushover message whenever the presence sensor is triggered. I have positioned the sensor on the inside of my hall. Thus it is acting as an automated doorbell.
    So as my guests are trying to locate my doorbell I am already on my way to open the door. ;)

    - Marius

    Attached Files:

  2. My XeThru doorbell has been operational for over a year now. Earlier I had a few false detections due to humid weather and wind which made the outdoor plants move and cause a detection. These have all been dealt with by setting a minimum threshold for the signal value and requiring a minimum time period of detected movement.
    After these minor tweaks we haven't had any false detection. But last Friday the system detected a visitor that didn't really intend to trigger the doorbell.

    My fiancée was home alone when a message ticked in on her phone at midnight, notifying her that someone was at the door. Her initial thought was that it had to be a false detection because of the late hour, and also got a bit annoyed by being disturbed by such an error. But still she went to the window to see if someone was there.

    In the darkness she barely got a glimpse of a person going around the corner over to the neighbour. She got suspicious and went upstairs to get a better view of the person. There she saw that he had gone inside the neighbour's storage room and was snooping around. After calling the police it only took them about 5 minutes before they were on the scene. The person vanished as soon as he heard the sound of the police car approaching, but the police caught him a couple of hours later. In addition to stuff belonging to other people, they found a letter addressed to our house on him that he had taken from our mailbox (an envelope from a charity with a couple of christmas cards and a letter asking for a donation, so don't know what he intended to do with it). The police brought him in to sleep in prison for the night.

    The funny thing is; not only did the XeThru doorbell do its part in stopping this criminal, but since this happened in Trondheim, he was very likely monitored by a XeThru sensor in his prison cell as well (https://www.xethru.com/blog/posts/xethru-respiration-sensors-pilot-project-norwegian-police). :)

    - Marius

    Attached Files:

    Lovexethru, Xióng, Olle Alm and 4 others like this.
  3. Olav Liseth

    Olav Liseth Administrator Staff Member

    Awesome update Marius! I need to set up one of those, anyone else using the XeThru doorbell?