[apalrd]

First, the design distance ('Ref Distance' on the calculator) is used as the time it takes to accelerate to that distance from stopped. I don't include decel time, just accel time. You would still be moving when you reached that distance. I did not write the majority of the calculator, it's JVN's.

Second, Time to Distance. Time to Speed is used to validate acceleration targets, to make sure shorter-distance movements might possibly be acceptable.

Third, this method was the easiest method to implement. It has some noise, especially at the start, so I filter the voltage. It seemed to work well enough.

The reason I calculate it iteratively is because voltage is needed to calculate torque in the mechanical portion of the calculator. So, I calculate voltage from the last iteration current, for use to calculate this iteration's torque. The voltage change per iteration is so small that I don't really need immediate accuracy.