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Unread 24-08-2009, 13:17
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Re: pic: 1010 Drive system prototype

Quote:
Originally Posted by joeweber View Post
...
I find it interesting trying to come up with a omni direction robot that is simple to build and has an effective pushing force. Swerve drive is complex and Mecanum is simple but less traction. Maybe somebody will come up with a solution some day.
Just thought about something after reading a couple of posts. In the few instances where the robot is trying to move forward, the middle omni wheels would essentially give the drive train 100% torque moving forward, and 71% torque moving sideways.

384 & 1086 seemed to have massively powerful mecanums in 2007 & 2008, and what I've gathered from them is it's all about gearing and how you try to push 'bots around. If your bot is square to the bot you're trying to push, so long as your bot is geared properly there shouldn't be a problem in pushing the other bot. Traction (as defined by the ability to convert torque into forward movement, which takes the roller angle into account)) is still a matter of what the rubber rollers are made out of and not the angle of the rollers.

Furthermore (and I just had this thought....), if your bot tries to push on the diagonal, (which should have the code only driving two motors at full speed), you only have 0.5 * 0.71 = 35% of the available total torque with the other two wheels acting as castors. This situation is probably where most people get their eye-witness accounts of 'mecanums can't push'.
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