Don’t want dogs pooping on the front lawn? You could put up a sign, your could chase them away like a crotchety old miser, or you could build a motion detecting sprinkler system. It’s pretty hard to line up for a doody when you’re getting sprayed in the face (or worse) with cold water.
The setup is pretty simple. The bump-in image above shows the view from a webcam. The server monitoring the video is running software that detects motion between one frame and the next. When it sees something in the right position it signals an Arduino to trigger the solenoid which has been holding back the water. Check out the movie after the break which shows [Phil Tucker] tramping across the grass to trigger the trap.
Sprinkler hacks are always a lot of fun. This variable-range sprinkler is still one of our favorites.