I knew someone who took a motion sensor, hooked it up to a sprinkler and turned it into a water sentry gun of sorts. Any time a cat came near the bird feeder for an easy kill, it got wet. The cats ...

As we head into summer, Super Soakers and their ilk become de rigeur ways to cool off in the heat. Not content with chasing targets himself, [Marcel] instead built a sentry water gun to do his bidding ...

If you need to keep out unwanted guests from your office, bedroom or private spaces then you may be interested in this awesome Raspberry Pi motion tracking autonomous sentry gun project publish to the ...