From jbutterfield on Instructables:

Every year on the last Saturday in October, the Cantigny Historical Museum holds an amateur catapult contest. This is a wonderful contest that allows all comers to build and fire a catapult while competing in up to 3 different categories: distance, shot grouping, and accuracy. For more information on the contest please visit their website at https://www.fdmuseum.org/event/cantigny-catapult-c… For this years contest my team, the Pi Throwers, decided to use a Raspberry Pi to help with the release portion of our throw.

In our design, we have a set of sensors being monitored by a Raspberry Pi Zero Wireless. After arming the catapult and pulling the release, the Raspberry Pi controls when the baseball will be released. Using this simple process, we were able to come in second place with a distance of 186 feet.

This Instructable will discuss the design, development, and implementation of the Raspberry Pi controller and associated electronics. Although I do not cover the building of this years catapult, look for an instructable after the start of the new year about the design and building of next years catapult.

Just for fun, I have included a video of our 186 foot shot. I hope you enjoy.

I would also like to thank my team mates this year: Steven Bob and Gus Menoudakis.

Read more and see more on YouTube

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