Our drive train has been having problems cutting out after long periods of practicing(sometimes short now). We figured we should change out the gearboxes and falcons on them. Its a 2 falcon gearbox per side ( https://wcproducts.com/collections/gearboxes/products/2-cim-ball-shifter ). All the internals are also replaced with steal gears. We haven’t had a problem like this until about 4 days ago. Since our drive train is basically brand new now and are still having a similar problem we suspect it might be something else. We are leaning towards problems with our PDP Power Distribution Hub - REV Robotics
can you supply some pictures of the gearboxes (inside and out) and connections to and from the PDP? Also are you running anything else while you are driving if so what and for how long?
The only thing that usually runs at the same time is the compressor but not for long.
have you tried putting it up on blocks and running it while monitoring the readout on the PDP Im not seeing anything immediately worrying about how yalls robot is did up. Are your gearboxes fully greased to the max? Do you have any video of the stalling?
We will try this soon to see what happens. The gearboxes we greased not to the max but enough to coat the gears
My thought is that after prolonged periods you might be browning out your rio if its not something with the REV PDP. Is there anything showing up in the driver station as the issue is happening? Make sure you do the tug test on all your wires to and from the PDP i have heard of them coming lose after a while unlikely that this is your problem but worth the 2 mins it takes to check. if you have video of it stalling that would be helpful aswell.
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Open up the logs on your driverstation (click the little gear above the console output section on the right):
There’s some check boxes on the right hand side to enable viewing the current draw of individual channels. Check off the ones that correspond to your drivetrain PDP channels.
Take a look at how the current draw looks on your drivetrain motors as the practice time progresses.
Compare current draw between left/right.
Look for main input voltage sag below 7V which will cause brownouts (should be accompanied by orange alert/warning dot at top of plot).
If you see significant discrepancies in current draw (note current will intentionally vary when you’re doing stuff like turning) check:
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You have good electrical connections between your motors and PDH.
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Consider setting current limits in your code.
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Look for extra mechanical friction on one side of robot (chain/belt tension, bad bearing, bad gear spacing/mesh, etc).
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Looking for an update did yall end up getting this problem resolved?
So we had not figured out the issue until the end of our qualification matches at SFR. Basically we got rid of voltage limits and redid the said current limits with proper code. We did not have the same issue again. (I’m not the programmer but that’s what I understand)
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Glad to know yall got it sorted sorry it took quals to figure out. Feel free to DM if you ever need any help!
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Thank you!
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