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Unread 18-02-2011, 23:56
Alectrolytes Alectrolytes is offline
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Mecanum Wheels Drive Chain Problem

When we test our mecanum wheels, going forward and backward is fine. However, when we strafe left, our robot tends to go forward as well, when we strafe right, it goes backwards. After jacking up our robot, we notice 2 wheels (wheels 1/FL and 4/BR) spin faster than the other wheels. I can't diagnose the problem since we thought it was a calibration problem. Maybe we're doing it wrong, any tips for calibration? Perhaps we're mixing up different CIM motors with different specs?

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Unread 19-02-2011, 00:08
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Re: Mecanum Wheels Drive Chain Problem

We had that problem before. We also noticed different in wheel speed. Check your key for the output shaft of CIM motor to hub. Ours were very loose and it came out quite often. Due to friction it still turns the wheel without the key but it would be slower because it slips a little. I hope this solves your problem.
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Unread 19-02-2011, 02:55
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Re: Mecanum Wheels Drive Chain Problem

Do you have any kind of closed-loop feedback on your circuit? (A gyro to monitor turn rate, or encoders to measure wheel speed?)

Jason
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Unread 19-02-2011, 03:06
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Re: Mecanum Wheels Drive Chain Problem

the cims loose power after a while. i find that they loose somewhere between 3-5 percent per year. so if 2 cims are new and 2 are old, swap out the old ones would be my advice.
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Unread 19-02-2011, 12:44
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Re: Mecanum Wheels Drive Chain Problem

Quote:
Originally Posted by dtengineering View Post
Do you have any kind of closed-loop feedback on your circuit? (A gyro to monitor turn rate, or encoders to measure wheel speed?)

Jason
We do not.


Quote:
Originally Posted by Hawiian Cadder View Post
the cims loose power after a while. i find that they loose somewhere between 3-5 percent per year. so if 2 cims are new and 2 are old, swap out the old ones would be my advice.
This is interesting, we just picked 4 CIMs from our motor box and put them in the gearboxes. I'll look into this.
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