Formula for controlling the movement of a tank-like vehicle?

Question

Anyone know the formula used to control the movement of a simple tank-like vehicle?

To \'steer\' it, you need to alter the force applied the left and right \"wheels\

Answer 1

Change in angle (in radians/sec) = (l-r)/(radius between treads)
Velocity = l+r

For the dtheta, imagine you had a wooden pole between your two hands, and you want to calculate how much it rotates depending on how hard and which way your hands are pressing - you want to figure out:

how much surface distance on the pole you cover per sec -> how many rotations/sec that is -> how many radians/sec (i.e. mult by 2pi)