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Unread 22-07-2013, 22:41
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Re: pic: 20's IRI Carnage

Quote:
Originally Posted by apples000 View Post
We've done this before with a PTO/brake setup where the wheels would lock when the PTO was engaged and the momentum of the whole robot could rip apart our hardened steel dog.
Our Ti dog didn't break and we could make it even smaller, but it was expensive and a MASSIVE pain to manufacture, so we had a machine shop (that a mentor worked at) make our second set for us. Unless you have a real need, and a ton of machining resources, I would advise against this.
The guy I asked happens to be a fan of Ti, which is why he mentioned it (He later suggested hardened steel would be perfectly adequate, in a different email).

Titanium alloys have a low modulus elasticity but high yield strength/ultimate tensile strength, and fairly low density. So it's springy but won't break easily, and it's lighter than steel for the same strength, which is perfect for this application. But machining it is more difficult than steel or aluminum, and welding it is also hard (not that this piece requires welding, but it's hard).

I like doing this kind of failure/material analysis. It's fun and I always learn a lot.
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