My neighbor loaned me her motion activated sprinklers for the deer problem. I installed one and the raspberry bushes seem to be recovering, at least somewhat. The shape of the bushes reminds me of the trees in the book The Lorax by Dr. Seuss.
I've unintentionally tested the sprinkler on the way to feeding the chickens. So far, I've been hit on my back and the side of the head. I hope the deer feel the same way I do when hit with a cold blast of water. I get a little irritated when the sprinkler looks like it's laughing at me after hitting me with a jet of water. I'll be installing a second one next to the fruit trees in the front yard.