Problem - Read from Closed Loop Stepper Motor while Rotating

It could well be a stepper motor is not the best solution . If it’s connected to significant mass for its power output , it may well miss steps during operation and certainly when there is kick back from the wheels
A conventional servo system with a DC motor/gearbox and feedback pot/encoder to measure rate/position - that is how electric power steering on a car works .

With a stepper motor the idea is you know where the output position is on the basis of the number of steps you’ve given it , same for rate of position change. So no feedback is needed, but if the load causes missed steps you’ve no chance. ( each step has to rapidly accelerate and move the mass)

A look at what is the “ state of the art “ is worthwhile…

A good read