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Unread 17-06-2016, 23:56
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GeeTwo GeeTwo is offline
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Re: pic: OmniSwerve chassis Bottom View and Concept Discussion

TL;DR Trying to wrap my brain around what this does and why you'd want to do it.

If all the wheels steer in unison, you have crab drive - with the inherent [crab] inability to rotate the chassis (not good for a triangular chassis in most conceivable games) and the additional [omni] weakness of being highly vulnerable to cross-drive forces. I don't see any way to get anything faster than geared speed in this scenario, either.

If only the wheel near the steering motor is steered, I can imagine a scenario where you can get up some extra speed, though I haven't done the math to convince myself it's viable. If this is the case, why are the two non-steered wheels built up so they appear to be swerve modules?

Or is something else going on (e.g. one of the wheels steers counter to the other two, or something even more arcane)?

Edit:
Quote:
Originally Posted by asid61 View Post
How are you getting above max speed?
Quote:
Originally Posted by Scott Kozutsky View Post
drive straight to max speed, turn left at 90 degrees and accelerate in that direction to max speed. Because of the omni wheels, you actually (ideally) don't lose your forward momentum after turning and, as such, move in both directions at your maximum geared speed, hypotenuse of that vector triangle is 1.414 times the side length.
Maximum speed is achieved when the drag/frictional forces are equal to the drive forces, and the drive forces are applied. Once you turn the drive in another direction, you'll begin to slow in the direction you are moving. You may be able to achieve a bit better maximum velocity, but after accounting for the longer distance traveled, I don't see how you can achieve a higher net speed.

Edit2: That is, at maximum speed, saying you don't lose forward momentum, even ideally, is not valid. Maximum speed is inherently the result of significant loss of forward momentum due to friction.
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Last edited by GeeTwo : 18-06-2016 at 11:42.
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