wvmarle:
For the target I'm more thinking of a mechanical switch, e.g. a push button that is easy enough to press that the impact of a nerf dart can do this.
Or maybe a piezo impact sensor?
Vibration sensors don't sound too suitable, as they will vibrate from impact elsewhere on the board.
wvmarle:
Forgive my ignorance, but I thought a piezo impact sensor was the same thing as a vibration sensor?.