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Unread 18-01-2006, 17:54
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Joe Johnson Joe Johnson is offline
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Re: Which motor is better?

There are many things that go into this, but in my opinion, based on power conciderations alone, the CIM motors are the only real choice for the drive train (with the possible addition of the FP if it is not the only motor used).

There are only 2 questions then:

1 motor per side or 2? And Which CIM motor?

If you go with 1 only, the extra power of the 330W motor and smaller size & lighter weight is too attractive too pass up. If you go with 1 motor, I recommend that you strongly consider shifting.

The question of multiple motors per side is tricker.

There are various combinations:
CIM 340W + CIM 340W = 680W
CIM 340W + CIM 270W = 610W
CIM 340W + FP 170W = 510W
CIM 270W + FP 170W = 440W

I think any of them can work but to be honest, I would stay away from the FP in a drive train because they tolerate heat and abuse less well than the CIMs.

It is sort of a toss up for me between the top two above, though I am leaning toward the 680W version.

I used to be firmly in the "1 Motor + Shifter" camp, but I have since become a believer in the merits of 2 motors per side for 2 reasons: it makes your robot peppier in terms of acceleration and it gives you two (2) 40Amp breakers to feed your drive motors.

As to shifters, with the advent of the Andymark.biz shifter and the NBD whitepaper on how to adapt a CIM to a 3 speed XRP Dewalt Drill Transmission, shifters are easier than ever to implement, even for a team with limited resources.

So...

...here is the bottom line advice, this year's Stylish Robot will have 2 CIM 340W motors per side + shifters.

You read it here first...

Joe J.
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Last edited by Joe Johnson : 18-01-2006 at 20:09.