Hello, our team is trying to make a flywheel. We are using two motors, connected to gears which spin the flywheel. We put in some blue motors, and they were running the wheel fine until suddenly they started slowing down to a complete stop. I don’t know what is happening, can someone help me?
How were the motors running before they stopped?
What gear ratio are you using?
If you let the motors rest for a while, will they work again?
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What gear ratio are you using? I assume you have proper friction reducing techniques such as dellrin bearing flats in place. Also, check to make sure your motors are good. If they are, run them off of the brain instead of a program, just use the diagnostics tool, and then you should know where the problem is.
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that’s a good point, they could just be overheated.
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Check for friction in the assembly and the temperature on ur motors. Friction will cause the entire assembly to slow down and will overheat motors and cause them to stop running if they reach a certain temperature level. Set ur brake type on flywheel motors to coast as well, if they arent already defaulted to that i cant remember. Lithium grease and other lubricants can help mitigate some friction also
Write some code to display the amps of each motor to the brain. Slightly loosen the bearing/mount/etc that your shaft goes through. Run the motors, watch the amps, slightly move the bearing/etc back & forth till you find the lowest amp reading. Tighten it down.
Check bearings for friction also. They should not feel ‘notchy’. Check shafts for straightness. Sand shafts. Check gears for damaged teeth.
Go over every single item in great detail using great care.
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There is a diagnostics tool that lets you essentially do this same thing without coding it. Just boot it up on the brain and run your motors. This is good advice, I just thought I would mention that there is an easier way to do it.
AFAIK your method only works for a single motor. It’s a good suggestion, and one I sometimes make, but it does not work for 2 motors.
I’m a big fan of writing code to display critical motor parameters to the brain. This tends to be lift/arm motor temp, flywheel/intake temp, or any motor that tends to overheat.
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Thanks for that catch, I forgot about the second motor. 
That gives me an idea for an upgrade…
The most likey thing is that the motors probably overheated, if not try to see if new motors work.
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Thank you all! The motors were overheated. They are working now. Though, the program uses a lot of battery. Do you know how I can make it use less?
Again, cut down on friction. Aside from that, you could change you gearing ratios. I also recommend that the flywheel motors be easy to hotswap, because that problem won’t be over for a while.
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You can try putting 100% torque in your program.
Don’t you love how the defaults aren’t %100? Actually, that can be useful for not having to fix designs sometimes, but still.
Just don’t use blue motors, they go out so quickly, use a gear ratio with green motors.
In order to get green cartridge motors up to flywheel speed you would need a compound gear ratio, which would be much harder to optimize and create unnecessary friction over using blue cartridge motors with a single gear ratio.
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Since the blue motors doesn’t have as much torque as the other two, I suggest using low strength gears. Btw what type of wheels are you using for your flywheels, I extremely suggest 3" or 4" flexwheels.
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