I need to electrically "sense" when a brick is thrown through a vertically-oriented pane of breakaway glass, breaking it.
My first thought was to paint a thin strip of clear conductive ink/paint/gel across the back of the glass, then treat it as a normally-closed switch to trigger the rest of the circuitry.
I need this to be reliable and reproducible. Are there any reliability drawbacks to this solution, and if so, can you suggest something better? I'd like the solution to be as passive as possible at the point of the glass (that is, I don't want to do something like mount a tiny digital accelerometer unit on the glass, as this would require much more effort than I believe is necessary).