Thread: Shifting while not going straight
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Unread 26-05-2013, 14:04
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Re: Shifting while not going straight
Quote:
Originally Posted by PVCpirate View Post
For logomotion, my team had a shifting and braking mecanum drivetrain. We used AM Supershifters with 1 cim on each wheel, and went for the pneumatic option to shift. I don't remember having any issues with shifting while the robot was rotating or doing anything else. The lower gear was mostly used for fine control while hanging game pieces. A student on our team also made brake pads for each wheel out of extra mecanum wheel plates, which immobilized the rollers to increase traction, and were also engaged by small air cylinders. Lots of pneumatics, but it did what it was supposed to do, and we won a Creativity Award for it.
With regards to the robot Anthony is talking about: We had a lot of problems with shifting while going straight because you only shift on specific point with a DOG shifter. This means that some wheels will shift before others. This isn't an issue with a gyro stabilized drive, but most teams do not have that. With mecanum, shifting can really mess things up for small moments (driving straight + shift could cause a slight rotation, or translation unintentionally). Most drivers won't notice these at high speeds, but in auto its a killer.