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Black Jaguars on old IFI controls
In case anybody was wondering, last night I performed a little experiment.
Our robotic forklift cart uses a power wheelchair as its base, and the controls were replaced with a 2004 IFI system, minus radios. Its motors were 24V.
We've been running the system off two deep-cycle marine batteries in parallel providing 12V at a combined rating of approx. 150AH. Running the drive motors at 12V, the cart has worked well since 2008 when we built it, but its always been a bit slow (it moves at a walking pace). Knowing that the motors were designed with 24V in mind, and knowing that the cart already has 2 12V batteries on it, (as well as a trailer we may be developing for it to extend its range, and provide an additional 350AH or so of batteries, along with inverters and so forth to run controls and tools) and knowing that the black jags we have will happily operate at 24V, we decided to give it a try, mainly because it would improve the power and top speed of the cart, and with the field being 1/2mi from the pit in Atlanta, we thought the extra speed might be nice.
I hooked up two robot batteries in series for the purposes of this test, powered up a black jag, and fed it a PWM wire from the 2004 IFI system on the cart. Works flawlessly. (I'm not sure why we have to differentiate Jaguars from Victors in the cRIO code, but I know it has something to do with the refresh frequency (200Hz on Vics, 15kHz on Jags?)). Does this mean that while the Jag is happily running, its just not running to its full potential?
For simplicity's sake, I tested the jag at 24V with a CIM hooked up to it (yes, I realize the CIM is a 12V motor, and running it on 24V could damage it. This CIM had already been damaged to the point that we wouldn't use it on a robot.) Wow. CIM's make a TON of torque on 24V as compared to 12.
In the end, we decided NOT to make the change, as it would require considerable re-wiring of the cart to provide a separate 24V rail for the drive wheels, while maintaining the 12V system for the controls and other accessories, as well as making the integrated charging system considerably more complicated, and considering we only had 3 days until the trailer has to be packed up, we decided there wasnt enough time to make the change and test everything out properly.
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