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Unread 26-03-2010, 15:46
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JamesCH95 JamesCH95 is offline
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Re: Engineering Challenge- Spring Loaded Kicker Edition

Quote:
Originally Posted by Ether View Post
This is very easy to see graphically. See the first attached GIF. The area under the curve of force vs distance equals stored energy. The area under the curve of the Weak Spring (shown in red) is larger than the area under the curve of the Strong Spring (shown in blue). Both the Weak and Strong spring areas have the same height, but the base of the Weak spring area is longer, so the area is proportionally greater (area of a triangle is 1/2 the height times the base).

Your analysis completely ignores pre-loading of the spring though. Most teams using spring-assisted kickers pre-load them.

By using a greater pre-load on a weaker spring, you can get more usable kicker energy at the same stall force and same distance. See the second attached GIF.



~
Very true. What would be even better, using this logic, is a constant-force spring. For a given usable length they are much smaller than a coil spring of the same rate. Check out McMaster.
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