Looking for ideas: What can be done with "movement detected" sensors?

I have some movement sensors inside the main areas of the house, courtesy of my DSC Alarm. These sensors give me instant “movement” information regardless of the alarm status (and especially while we’re at home and the alarm is unarmed).

I’m looking for some ideas. What else can I do with it?

So far all I am doing with it is to store the everyChange into influxdb to plot this graph.

It isn’t really a good “there’s a person in the room” sensor because what if that person sits still for two hours watching TV or reading a book? I can’t turn off the lights just because it stopped sensing movement.

You´re asking a question which you already answer yourself.
A motion detector can be used to anything you want it to. But ofocuse there may be situations where isn´t not that usefull… Like you say, turn ON the light… But what if the person sit still for a long time.
In case to know this, you´ll have to monitor how long this person sit still (normally). I doubt anyone can sit that still for hours.

So if you monitor the behaviour, and “normally” the person sit still for ½ hour… Then you can create a rule to set the timer to 35 minutes… If the person havn´t moved in 35 minutes, then turn off the light.
Thats the way to use a motion sensor for lights. You´ll have to know the behaiour of the persons involved, and you´ll have to set the timer long enough.

This is also the reason why I seldom use motion detectors in specific rooms like children room, bathroom etc… But I do use it in kitchen, corridoors, halls, my garage etc. Places where persons travel through the place/room, and/or not sit still for a longer time. I would never use it in livingroom, bedroom etc… It´s not worth it. Bathrooms could be used. I know many who does it. But you have to take into concern, if the person is taking a shower, your motion detector might not register the movement. So once again, you´ll have to create a timer long enough for the person to finish the shower, and starts moving outside the shower cabin. Or setup a second motion detector in the shower cabin area, and pray to, that noone falls asleep while showering :smiley:


This is where the “Wasp in the Box” algorithm might apply. The basic concept is if you hear a buzz you know the wasp is in the box. As long as the lid remains on the box you know the wasp is still there even if the wasp goes silent. If the lid opens and the wasp goes silent, you can assume it flew away.

The big challenge with this algorithm is determining when the box lid is opened. Depending on where your motion sensors are, perhaps you can use the motion sensors from adjacent rooms. For example, motion started in an adjacent room shortly after motion was detected in the current room and motion stopped in the current room so assume everyone left.

But ultimately, motion detectors make a really poor indicator of room presence. They are a little better, using WitB for home presence since you can use the opening and closing of the exterior doors as the “box was opened” indicator. But there are still lots of cases where you might be present and it will determine you are not.

I think most people abandoned the use of motion senors to determine presence.

For controlling lights, see Kim’s suggestions. Personally, I only use motion detectors in three places: back yard, garage, and closet. And I use “dumb” motion sensor light switches (no integration with OH). I am not among those who insist that all automatons must be integrated with OH. If I can achieve it more simply in a way that is stand alone I’ll go that route.

1 Like