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Thanks for the Kudos, Matt.
I was one of the Motorolans that worked on the current-sensing (err.. StangSense) for Wildstang.
We basically did what was discussed here earlier, taking a known voltage difference across a known resistance to get current. That was accomplished by using a known length of known guage of wire, to which you can find the natural resistance of, and finding the voltage difference across. That voltage difference was piped into a Maxim current-sensing op-amp (can't recall the part number offhand), which made that voltage difference (on the scale of mV) and converted that to a range from 0-5V.
That value was then piped into an HC08 uprocessor, through an A-D, and we used the HC08 to do some time-averaging of the currents of the eight inputs (4 drive motors, shooter, conveyer, etc).
All of this was then sent to the Robot Controller through a few of the analog and digital ports, and sent to the player side, where we had a color Palm processing the data, showing live current values, max current values, etc. We also had the ability to save that data during each match, so that after wards, we could look at/analyze why our current spiked at some particular moment, or what drive motors weren't spinning, etc.
Definitely a lot of work, and a pain in the rear to solder together, but it was a fun little adventure!
-Nate
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