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Unread 10-12-2004, 21:30
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JVN JVN is offline
@JohnVNeun
AKA: John Vielkind-Neun
FRC #0148 (Robowranglers)
Team Role: Engineer
 
Join Date: May 2001
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Re: Shifting Efficiently

Quote:
Originally Posted by Mike Betts

Is there at Mechanical Engineer out there to set me straight?
Mike,
You are 100% correct as far as robots go. I'm not familiar with ICU's but that is how DC motors work.

Refer to attachment:
This is just a quick graph showing some random motor (a chiaphua, actually) with 4 different gear ratios. 1:2, 1:1, 2:1, 4:1.

You can see in the plot how in order to maintain optimal power usage at all speeds, you need to "bounce along the peaks", and shift where the plots intersect. Ideally, you could use a CVT to vary your gear ration and ALWAYS stay at max power (rather than bounce up and down).

Hope this makes SOME sense,
John
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In the interest of full disclosure: I work for VEX Robotics a subsidiary of Innovation First International (IFI) Crown Supplier & Proud Supporter of FIRST