A New Pet Use Case -- Human-Immune Motion Detectors

I have scoured the community and have yet to see this idea discussed.

We have a small dog (15 lbs) who we have trained to go to the back door when she wants to do her business. Since we have a busy household, and there were times she sat there for 10 minutes or more before anyone noticed, I put a motion sensor near the floor that triggers our whole house audio to tell us that the dog needs to go out. Simple enough, and effective…for the most part.

The problem, of course, is that human beings walk by that same back door from time-to-time and trigger the ankle-level motion detector. Which then falsely triggers the voice message to let the dog out. In a sense, I’m trying to create the inverse of a pet-immune motion detector; I want a human-immune motion detector!

So, what are my options for triggering based on presence of a small dog?

  • Get a second motion detector. Place it at “human height”, block off this detector’s downward vision, and then write a piston that looks for situations when the low motion sensor is activated while concurrently the high motion sensor isn’t activated. That’s probably workable, but ST makes me nervous when you have to play with timing.

  • Use a pressure mat (discussed elsewhere in the community). Problem is, my dog is not that accurate with where she sits.

  • Just get a doggy-door. This would obviate the need altogether, but there are other reasons we can’t go this route in our house

  • other ideas?

Very curious to get reactions and ideas from the community on this.


All the ideas sound good. :dog:

Assuming your dog is not deaf, she should learn that sitting on the mat triggers the sound announcement, which in turn causes you to come in. So I think you’ll find she will learn to be precise if it gets her what she wants. :wink:


As JDRoberts says your method is sound. My daughter did this using old fashioned method, trained the dog to use a string of bells hanging from the door knob. That removes the human factor. But saying that try the second motion sensor or the mat connected to a Ecolink or MonoPrice door window sensor as a transmitter.


You could put a leak sensor on wall (sensor contacts pointing out) and teach the dog to lick it when it wants to go out. Leak sensors have two little contacts that sense when water, or a wet tongue, make a connection between the two contacts. You can test with a wet finger. Dry fingers won’t work.

Training her to trigger it should be pretty easy. When you find her at the door put a small bit of peanut butter above the contacts. She’ll lick it triggering the sensor. Wait for the audio to sound and then praise, praise, praise, then open door. This will help her associate the lick, then sound, then praise is all part of one activity/reward. After a while you can remove the peanut butter part.

This should keep it human-immune unless someone really wants peanut butter. :slight_smile:


While we’re at it, we did have a discussion last fall about which buttons are easiest for dogs to push. My own dog prefers the logitech pop buttons, which are big and rubbery. :dog:


Thanks guys for the feedback and ideas. Best part about ST is the community, I swear.

Think I’m gonna go with the double motion sensor option. It requires the least dog training, and I can use it to trigger actions for humans and pets separately.

Has anyone successfully used some material like tape to block off a portion of a motion sensor’s “eye”? Anything more involved than the obvious/?

The obvious works: people use both tape and tubes to narrow the detection field. :wink:

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Electrical tape works just fine, I use some white tape on one of my motion sensors and it’s hardly even noticeable.


I keep saying I am going to pretty this up a little but haven’t gotten to it yet. When I walk from my office (from where the pic is taken, into the bathroom, my hall light never turns on. But when I cross the door jam plane, it does. My suggestion is to play with the positioning of both the sensor and tape until it’s perfect. Pretty simple actually.


Perfect, thanks guys

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