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Unread 09-01-2013, 08:03
Anupam Goli's Avatar
Anupam Goli Anupam Goli is offline
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FRC #1648 (G3 Robotics)
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Re: Mecanum vs Treads

Quote:
Originally Posted by MARS_James View Post
I don't understand this at all, how does the bump make mecanums not work? We used them last year and got double or single bridge balances very easily
It has to deal with weight. Meccanum drive relies on an even weight distribution on each wheel for accurate strafing and turning. if you don't have that, the robot will strafe in a slightly offset angle. Introduce a different height for 2 wheels, and suddenly your back wheels have more weight than your front. It only affects strafing though, if I remember correctly.

Also, some non selling points for meccanum:

Actually learning to take advantage of strafe is harder than it looks. Have you ever played Halo and strafed at all? I don't think i've strafed at all when fighting in Halo 4. I'll bet when you play halo, the majority of the time you move the player's orientation and have him walking in that direction instead of strafing. The only times I strafe is to snipe and to avoid shots, both of which probably won't be done in this year's FRC game.

Meccanum also uses the vectors of motion on the wheel to produce strafing motion. Unless your PID is tuned to godly precision, you're always going to have some cancelled force, reducing your strafing accuracy and your power.

Also, the coefficient of friction on those wheels is low. Unless your control system has taken account for your driver
s tendencies, its going to be a lot easier to slip and waste even more drivetrain power.

See if these outweigh any advantage you think you may be getting. I don't know, they might for you.
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Last edited by Anupam Goli : 09-01-2013 at 08:08.