Hello everyone, I was wondering what gearing ratio you guys are using for your flywheel in this year’s problem. Currently our team is having trouble what gear ratio will work best for this year’s problem and we wanted to know your guys thoughts. Thank You!!!
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What gear ratios have you tried?
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Check on youtube. There are a decent amount of teams that have posted videos of their flywheels and gear ratios. It’ll also help you get a feel for how far it can shoot. I’m probably going to run with a 7:1 4200 rpm flywheel.
I have tried a dual gearing system where a v5 motor with a blue cartridge is conntected to a 84 tooth gear. That 84 tooth gear is driving a 12 tooth pinion. Additionally connected to that pinion is another 84 tooth gear which is driving another pinion. The problem with this gearing ratio is that it burnt out the motor completely. So our team changed the motor to a green motor and well it takes to long to get to max speed.
So you’re running a 49:1 compound gear ratio on one motor? That would be around 29400 rpm which is way too much. That’s how you burned a motor out so quickly. Try a lower gear ratio and keep on using the blue cartridge. Try simple gear ratios like 7:1 or 5:1. Finally, try two motors instead of one because one might not be enough to shoot the disc optimally. Also, a ratchet gear would help a lot in terms of relieving additional stress from the motor.
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Oh my gosh thank you so much for this information, I really appreciate it I will defintley keep this in mind. Thank you!!!
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Hi, I had a question about something in your post, but I don’t want to create an entire new post about it, cause it isn’t that important.
You mentioned that using a ratchet gear would help relieve stress from the motor in a flywheel.
From my research I thought that a ratchet gear is used to either make an axle only spin one way, or make one motor do two different functions depending on the direction the motor spins. In fact, wont the pawl clicking on and off the gear add resistance against the motor?
Im not understanding how a ratchet gear would help. Im probably missing something obvious here so let me know.
The ratchet is there so when the motor cuts power to the flywheel, the flywheel can keep spinning by slipping on the ratchet.
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The ratchet is being used as an ‘over-running clutch’.
Think of the freewheel on a bicycle. You can stop pedaling and the back wheel keeps spinning.
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This also has the added benefit of preserving motor health when power is cut from the robot (all that extra Ke gets put back into the motors, causing them to spin): REX 1727B-Ratchet and Pawl Device - YouTube
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