Calculating Linear Force from Motor Torque?

[AdamHeard]

Originally Posted by ksafin

Gotcha, thanks so much!

Just a quick question.

Right now we have it set up such that the motor has an 80 tooth gear, turning a 40 tooth gear, which is on the same axle as a rack and pinion gear (32 tooth I believe).

I feel like the calculation is a bit different in this case.

My assumption is that I can say the motor torque "doubles" from the gear ratio, lending to a 283 * 2 oz-in torque on the axle w/ the 40 tooth and pinion gear.

At this point, do I use the radius of the pinion gear to determine linear force on the rack and pinion?

Correct. Don't forget that free speed will be halved by that ratio as well.

For a Given gear ratio N, To = N*Ti and wo = wi/N.

To = output Torque
Ti = input Torque

wo = output speed
wi = input speed

I'd wager you already knew that, but I figured others reading might not.

Also, for multiple stages of gear reduction, lets say N1... N4. The total reduction Ntot = N1*N1*N2*N4.

EDIT: Magnets is correct that each stage of gearing will cause some energy loss. However I do disagree that a significant safety factor is always necessary.