It is hard to break a glass with a wire. If you look at your video there appears to be a ball bearing attached to the wire, so the wire retracts quickly and the ball breaks the glass.
The obvious thing to use is a spring because you can use a very small trigger to release a lot of force. The trigger could be mechanical or electrical.
You have not given an example of the "slap" motion so it is hard to know what is required for that.