Water Release Mechanism - HELP! Answered
I've been racking my brain trying to figure this one out, and thought I'd ask you guys.
I'm building a project which requires the release of a tethered "buoy" once this sinkable object hits the water. I know I could use a mechanical release - a water sensing probe that trips a servo release - but I would rather keep it really simple, and use just chemistry and/or physics to do the work, and somewhat quickly, within a minute or two.
I'm thinking that something must dissolve, expand or contract quickly when in water so that whatever is holding the buoy to the sinking object releases, and the buoy just floats to the surface.
Making a toilet paper "fuse" has come to mind, but I was hoping for something more solid. I considered salt (as formed into a salt lick) but because it's so dense would take a long time to dissolve. Sugar cube seems too fragile?
Any thoughts would be appreciated!