Sorry, I have a day job that's been keeping very busy.
Right. So let's get down to
Doing the Math :wink:
Presenting the problem simplistically:
It is similar to calculating Force (Torque actually) at two different radii (see the link). Borrowing my diagram from the other thread, let us presume that r1 = turning radius of the outer wheels, and r2 = the turning radius of the inner.
Quoting myself, "The
Force Law of Equilibrium implies a balance of opposing forces within a system."
We know the values of r1, r2, and F1.
If r2 = inner turning radius = 36", and your vehicle width = 36", then r1 = 72"
Checking, r1 - r2 = your vehicle width.
F1 = 100% Throttle, naturally; lets call the value = 100. Calculate the value of F2:
r1 x F1 = r2 x F2 =>
F2 = (r1 x F1) / r2
Therefore:
F2 = (72 x 100) / 36 => 7200/36 => 2*(6*6)*(4*5*5)/(6*6) => 2*(4*5*5) = 200
So F2 requires 2X the value of F1 to create the same effect, however
Angular Velocity in terms of percentage at r2 = F1/F2, therefore you need 100/200 or 50% Throttle to drive the inner wheels at the same speed as the outer wheels.
However, as we calculated - the force required on the inner wheels is twice that of the outer which means that we need twice the Current (I) as in Amps to provide equal traction in muddy conditions.
In reality the problem is a little bit more complicated than I've explained because we have described one axle, the REAR axle, and not the Front axle or the box shape of the vehicle or the affects of drag between the front and rear axles; I really don't think we need to go that far. You have a good generalized answer and a formula for calculating Throttle verses Inner and Outer wheels should you decide to change the parameters.
Clear as mud?
Watching the crops grow,
KF