How would I go about simulating a catapult? I have an arm on a torsion spring, and I want to be able to pull the arm back to whatever displacement angle and then let it go. What kind of study should I be using?
What exactly do you want to simulate? The catapult after release but prior to the impact with the stop? What do you want from a results standpoint? Stresses? Structural deflections? Internal forces? What you're after determines how you should simulate this and how much effort will be involved (which can be quite extensive).
This is definitely the right questions to ask.
the short answer is most commonly these are done in motion.
You can try Motion. There should be sample with cathapult in Training book.
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