RC Lego Catapult
When I was building this I wanted a high-tech catapult because we live in a high-tech world, and most catapults are kind of low-tech. So, I made this one remote control. An M-size motor tightens a string which pulls the swing arm forward. I experimented different length arms, and found that this was the best. I wanted to post a video, but I don't think it's working.
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