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Unread 03-10-2013, 14:32
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Ether Ether is offline
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Re: Plotting Location w/ Accellerometer Project

Quote:
Originally Posted by Chris Hibner View Post
In past years when we needed high accuracy during turns and/or expect collisions or other sources of wheel slip or orientation change, we put the encoders on non-driven follower wheels. We put the wheels in line with the drive wheel, usually on a swing-arm and spring loaded them to keep in contact with the floor. The VEX omni wheels work great for this. In fact, doing it this way allowed us to remove the gyro, which was nice.
Chris,

You might want to point out that 3 follower wheels are required if the vehicle has strafing capability.

Also, with 2 followers it is important to realize that they cannot discriminate among the three motions illustrated in the attachment (showing three skid-steer vehicles each with a different center of rotation). This can be mitigated by placing the followers so that the midpoint between them is on the center of rotation of the vehicle.


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Last edited by Ether : 03-10-2013 at 16:05.
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