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Unread 04-01-2011, 13:28
Unsung FIRST Hero
Al Skierkiewicz Al Skierkiewicz is offline
Broadcast Eng/Chief Robot Inspector
AKA: Big Al WFFA 2005
FRC #0111 (WildStang)
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Re: Modeling motor control

Marshall,
If your desire is perfectly accurate current then the answer is no. If you are trying to model some sort of feedback loop, then the answer is yes. It will take some experimentation and noise filtering but teams did use current feedback through the CAN bus last year. Can you answer how you measured the voltage? The reason I ask is that except for the low pulse width signals, the voltage to the motor is swinging between 0 and power supply volts or ~12 volts. The average voltage can be calculated from the pulse width but may not be accurate. For those that are trying to correlate real world performance to the manufacturer's published data need to remember the the factory testing is performed using a high current, lab grade, low impedance, stable voltage source. The battery, wiring and Jaguar do not come close to factory testing so although one can come close, there is no way to exactly duplicate factory published data.
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Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
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Storming the Tower since 1996.