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Unread 13-01-2005, 13:07
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Joe Johnson Joe Johnson is offline
Engineer at Medrobotics
AKA: Dr. Joe
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Re: THE Fisher-Price Motor Spec Sheet

Quote:
Originally Posted by gwross
I like your solution better than Dr. Joe's. But please tell: Are you proposing a EE solution that steps down the voltage outboard of the Victor, or a software solution where the PWM signal is limited to a precalculated value, so that the effective voltage at the motor is 9.6v? (Or something else? Will the Victors work if you limit their input voltage?)
Do you object to the complexity of the algorithm or to proposed operation? I think several teams did something very like this to stay right on the edge of the 120 Amp breaker from tripping in the 2002 Season. I don't think it is that complicated and I think the performance of the motor would be significantly better than the performance via limiting to 9.6V. 9.6V would still very easily fry this motor under some conditions while at other times (at the beginning of the match for example) it would limit the output needlessly.

As to whether Andy is proposing putting 9.6V on the input side of the Victor or limiting it in software (via max. & min PWM outputs), I don't know how you could actually put 9.6V on the input side of the Victor within the rules of FIRST.

Joe J.
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Last edited by Joe Johnson : 13-01-2005 at 13:13.