# Motor Degree to Distance and Turn degree

Hello, I just got into precision control for VEX V5 robotics. What would be the conversion formula that is able to convert the Encoder degree on the motor to the distance that the robotics will move and the formula that is able to convert the Encoder degree on the motor to turn degrees? E.g how many degrees do the motor L1 L2 R1 R1 need in order for it to turn 90 degrees. I forgot the formula but I am pretty sure it has something to do with trackwidth, gear ratio etc.

Thanks for any help!

Driving forward
Pi x Wheel diameter / 360 = distance per degree

4" wheel example:
3.14 * 4 / 360 = .0349 inches per degree

To travel 24 inches:
24 / .0349 = 687.679 degrees of rotation.

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Turning
Looking from the top of your robot you need to identify Track Width which is the distance between the center of the left and right wheels.

If the Track Width is 16" then 16 * 3.14 is 50.24 inches. This is how far the robot would need to travel to spin 360 degrees. 50.24 / 360 degrees is 0.139" per degree of robot rotation.

You will also want to divide that calculation in half so that one set of wheels moves forward and the alternate side moves backwards. This will keep the robot rotating on center.

So a 90 degree turn to the left would be 90 * 0.139 = 12.56.
12.56 / 2 = 6.28.
The right motor(s) would move forward 6.28 inches and the left would spin backward 6.28 inches.

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