How to build a remotely activated spring-loaded glass-smashing special fx rig?

Hi all,

I need to design/build a special fx rig that I can use to remotely break glass doors in a cabinet for a tv show. I've looked at the glass poppers sold at fx shops but they use squibs; this is a hidden camera prank show and the victim of the gag has to believe the glass smashed because they were singing in a high-pitched voice, so I can't use the squibs (the victim will hear them go off). Also, the glass is candy glass.

I am imagining something like the hammer on a gun; something that I can cock and leave set in the cabinet, then perhaps pull a string to trigger it into hitting the glass.

Anyone have better ideas?

Many thanks,

Damian

Something electrically triggered ?

SIze limits ?