Output and Input Drivetrain Programming With Gear Rations

Hello VEX forum community, when programming your drivetrain you have the option to program in the specific gear ratio you have on your drive train. We do have a gear ratio, a speed ratio, but when you enter in the values, what does it change? Do the motors work less, so the robot doesn’t go at an incredibly quick pace, or does the robot’s motors instead work harder to better optimize the speed of your robot? What is happening behind the scenes there? If I enter in a one to one gear ratio into the input values will it hurt the way the robot drives in anyway? Will the front wheels moving faster than the back ones cause any issues?

Thanks for your help,
10Xtothec

P.S.
Gear ratio is 36 to 12 tooth, and that 12 tooth (Being pushed bye the 36) shares it’s axle with a 36 (36 on top of 12, speed transfer, this 36 with the speed transfers it’s speed into another 36 (1:1). I think this is the correct way to simply say this 3:1 gear ratio. (On front wheels)-Correction that would be a 1:3

When you tell the drivetrain to “drive forward x inches”, it needs to figure out how far to turn the motor (in degrees) in order to get the robot to move the desired distance. If your wheels are geared down 3:1 relative to the motors, then the motors will need to spin 3 times as far to get the wheels to move the desired amount – that’s what those “gear ratio” boxes are for.


Yes, that will cause issues – all the driven wheels on a drivetrain should be moving at the same speed.

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