Should I use gear ratio on my robot’s wheels?

So, I used gear ratio on the wheels of my robot to make it really fast. The problem is, now it is really weak, skids, and gets pushed around. When I switched the ratio to make it powerful, it became really slow. I’m wondering if I should just rebuild the thing without gear ratio. Any recommendations?
Thanks.

A gear ratio simply modifies the speed to your liking.

Going without one would either make your robot really fast (>80 in/sec) or really slow (<40 in/sec)

Just wondering, what were the gear ratios and motor cartridges you used on your robot? A good ratio this year would be 66-77w on around a 60-65 in/sec gear ratio.

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Catalogue of Drive Gearings

Here’s a resource for drive gearings

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Thank you, @Gigahertz.t and @Money .
The drive catalogue helped. Also, this is only my first year of VRC so I’m not sure what the motors and gear ratio are. My robot is pretty fast without gear ratio though.
I will see if I can figure out which gear ratio I used.
Thanks!

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Do a 480 on 2.75 inch wheels. It is a solid ratio and 450 on 2.75 is kinda slow imo.

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Thank you, @Wesley13406D ! Unfortunately, I only have 4-inch wheels. Also, @Gigahertz.t, I figured out my gear ratio; it’s 3:7 from motor rotations to wheel rotations and I have 4 motors that are 11w each.

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Switch to a 66w drivetrain, or a 55w if possible.

What color cartridge are you using for your motors? But anyways, here are the gearings for a 3:7 :
Blue (600rpm): 54 in/sec (a little on the slow side, but competitive)
Green (200rpm): 42 in/sec (really slow)
Red (100 rpm): 20.94 in/sec (R.I.P. you’re a turtle)

If you think 54 in/sec is really fast, it is actually kinda slow for this year. Your bot getting pushed around is due to the fact that you are using only 44w of power, whereas your opponents most likely are using 66-77w of power.
I would recommend doing 1:2 ratio (using 36:72) on 6 11w blue (600rpm) motors (63 in/sec). Train your driver for at least 2 hours to get used to this.

If your robot is skidding, try putting a 4in traction/4in 60a flex wheel in between 2 omni wheels.
Btw, happy cake day @Xenon27! (even though you’re not here…)

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What gear ratio would you recommend without a 72 tooth gear? I don’t believe we have those

Definitely do a gear ratio. I would recommend doing a blue cartridge (600 RPM) and a torque gear ratio. I agree with @Gigahertz.t that more power will definitely help for this game.

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@68031B , I don’t know much about this so you probably want to wait for @Gigahertz.t , but I would think you could use a 24:48 or a 12:24. That way, still have the 1:2 ratio.

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@Gigahertz.t , I found out my motors are currently green motors. However, I think my robot is actually pretty fast. It’s simple and light, and it may have been the fastest robot at both of my tournaments this year. I will see if I can find the in/sec speed.
Thanks!

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You can’t use small gears like those because they aren’t bigger than the wheel so the axle of a gear would need to go through the wheel, which would cause the wheel to get stuck in the axle.

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I agree that nobody probably want to use the small gears, but theoretically, you could.


(This isn’t a good idea but it would function.)

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Yeah, these are the onlynother options for a 1:2 ratio.
However, doing this will require a lot of idler gears, plus using 4 in omni wheels would potentially ruin shaft spacing, leading to you cantelivering some shafts.

I would recommend just finding a different gear ratio.

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So we are currently using a 1:1 gear ratio with green motors. Would the best option to just use a 84:36 with red motors? We only have 12,36,60, and 84 gears.

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i think you guys forgot 72t and 36t gears exist lol, which is the only way you can run 1:2 ratio on 4 inch wheels

These rpm timings seem inaccurate. My robot is a 240 rpm drive, 8 wheel, 6 motor (blue, geared for torque) and it’s faster than almost every bot we go against.

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They are probably talking about high ranking high school teams

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Maybe even high school worlds or college. Because I’m in JR High, but I play high school teams, and my robot is pretty fast and has seemed like the fastest at the tournament when it drives straight.