I’m currently unhappy with the glass-break sensors that are available commercially. I won’t rehash my complaints here, you’ve probably all heard them before. I was brainstorming with a friend and not coming up with anything better idea-wise though, and he suggested the conductive paint used for rear window defrosters on automobiles.
They do sell the paint/epoxy for repair kits (hadn’t heard of this til he mentioned it).
Now, I have no idea how you could retrofit this, and given the cost for new windows (even cheap stuff off the shelf at Home Depot runs about $400 each for standard sizes, custom stuff commonly runs upward of thousands each) it probably isn’t cost-effective to have someone build them for you.
I think you’d have four traces which could be close to the edge of the panes or potentially even hidden by the sash and rails, maybe even having an appearance of being decorative.
There are a few assumptions here. First off, if the window cracks but doesn’t break completely, would that interrupt the trace enough to be detectable? Second, that you could even have a powered device in the moving part of the window without massively over-engineering it. And finally, how long would this even last? I don’t think the rear defroster in my car lasted 6 months before there were cold spots in it that didn’t melt. Oh, and don’t forget the double/triple pane stuff (would this go on the exterior pane, the interior, or both?).
Also it’s quite a few gpio pins to dedicate to even a single window.
May I ask what are you trying to achieve? A trigger when window is broken? Have you look into motion sensor and maybe Zigbee/Z-wave dongle? Less work and don’t have to touch the window. Plus, future expansion of mesh network.
I have a few radios in my Rpi, but no Zigbee or Zwave. I do want some sort of trigger for broken window panes… a motion sensor detects something far different than that.
This isn’t about “less work” so much as it is about doing things the right way.
Most of the HA stuff is wifi, but I am thinking about trying to use 1-wire for some sensors (temp and humidity mostly, maybe reed switches). And a few will be directly hooked up to gpio.
Got it. Don’t be to offended. Right way sometimes can cost you an arm and a leg. Laser reflective beam can also be used.
This is more theoretical at the moment. Though, the stuff is cheap enough that I can experiment. Panes of glass are cheap enough, the material’s cheap enough. Actually thinking about tinkering.
Might even figure out a way to retrofit, in which case it could be within the realm of the possible. Or hell, maybe I start selling it as a product somehow, dunno.
I see, well good luck, let us know the outcome. Also, try to keep “aesthetically appealing”, not like windows in 1980’s with silver perimeter wires :)).
Well, see… I honestly don’t know enough about window construction. I keep wondering if those could be hidden entirely by the frame elements that hold the pane itself. And my original mockup is just wrong… there’s a better geometry that only needs one gpio pin for the entire pane. Didn’t occur to me at first.
Will stop back with an update if I figure out anything interesting.
