Is there a difference in terms of sensors? I ask because I have a really cool idea I wanna try with the bins for cat and dog food we have. They have giant smooth spin on and off lids and if I can can acceleration (and not just vibration) to register when they are spun I can set up a "animals need fed" type automation.
In the real world an accelerometer would measure G. A constant vibration would be in Hz, possible after some Fourier analsys or what have you.
In the HA world they seem to be synonamous so spinning would not be detected as true acceleration but because it can never be smooth you will get vibration - variations in acceleration.
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This is exactly what I was suspecting. Ah well, it was a cool idea.
There a lot of crossover in these two devices. Vibration is a type of acceleration. (cyclic vs linear)
In the few sensors I have that sense acceleration, vibration will trigger them.
What are you thinking of doing?
The lids on these cat and dog food storage bins spin off. I thought it would be awesome if I could tuck sensors in the back side of the channels in the lids to detect if they have been opened (animals fed).
The siamese triggering device is notoriously unreliable. TONS of false alerts.
Two options that I can think of... Iām sure there are others!
- Put a motion sensor inside - will detect motion once opened
- Put a contact sensor on the lid, will report open when unscrewing the lid (then closed and open again a few times, but you could handle this with a rule and a virtual button to say it has been opened)
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I would think an acceleration sensor would experience acceleration away from the center of the lid when it rotates. Have you tried that?
Put a lux sensor on the underside of the lid, and lay it bottom up when you open the container.
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OH! I didn't think of that! Then I can tweak the thresholds.
I have a Xiaomi Miji Lux sensor. It is terribly slow. One might be able to take the cover off and replace before there is a response. Others might be faster.
If the lid orientation when "closed" is consistent enough you might try a small contact sensor. These respond immediately.
Update: Sorry I didn't realize Sebastien had already suggested the contact sensor.
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You don't just spin the lids, you pick them up and possible set them down. Surely that would trigger acceleration and vibration. I'd just go with a motion sensor, it seems a sure thing. Contact sensor may not work, depending on the threads.
I have wanted to get more out of the ST Multi in a similar respect but not sure how. IF that cat food lid was spun with one of these on the back there would be a fairly unique signature of axis offset and amount which would be a different signature than the cat jumping up on it causing a more random offset from static.
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I really think you're on to something with that idea! I totally forgot about the axis attributes. In my case, since the lids are angled when they are on, it may be possible to use axis readings trigger something.
