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Unread 31-12-2009, 15:12
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@JohnVNeun
AKA: John Vielkind-Neun
FRC #0148 (Robowranglers)
Team Role: Engineer
 
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Re: pic: Chassis Idea

Quote:
Originally Posted by Jared341 View Post
Dead axles are useful because:
  • You are minimizing the rotational mass of the wheel assembly and therefore maximizing efficiency since the shaft itself doesn't need to spin. Unless you have a truly massive axle or bad bearings/alignment, however, we're probably not talking a huge difference.
  • In the cantilevered case, you are minimizing torsional loads on ball bearings with dead axles (since the bearings are still centered on the axis of rotation no matter what the deflection of the shaft).
  • The closer together two bearings are, the easier it is to have them stay aligned. In a dead axle setup with two bearings in a single wheel, alignment is trivial. Live axle systems that support both ends of the shaft can get out of alignment more easily.
Did I miss anything?
We also use dead axles as structural members of our chassis (a round axle with tapped ends = chassis standoff.)

If you get creative with your axle placement and the structural design of your chassis this can eliminate the need for other structure and result in a lighter overall system.

-John
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