Velocity

Just as there are two displacements, there are also two velocities. The linear velocity is $v_{L}$, whereas the angular velocity is $v_{A}$. For stepper motor designs, it is important to derive the velocity of each wheel. This is quite simple. The left motor velocity, using our convention (that left-forward is positive for angular), is $v_{L}+v_{A}$. This means the velocity of the right wheel is $v_{L}-v_{A}$.