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Originally Posted by Joe Johnson
The situation is actually even more complicated in that the brushes do not magically switch off one set of inductors and switch on another. There are parallel current paths with inductors doing what they do ... acting as inertia for current flow. It is even MORE complex in that the width of the brush can sometimes be about the width of a commutator and you can get three parallel current paths rather than the more typical. For example, auto industry specs often provide relief from current draw specs for momentary current spikes due to such brush bridging.
Beyond this complexity there is ...
I could go on, but I don't think it is helpful.
For all cases I know of in FIRST, the inductance of the motor is a negligible effect. The only small asterist that I will provide is that the inductance plays a role (along with the PWM frequency and other factors) in the effectiveness of the assumption that we often use that PWM value given to the Victor is a good approximation of the Voltage applied to the motor (this effect is more pronounced at lower duty cycles). But even this effect is likely to be a noise factor in almost any control scheme teams are likely to employ on a FIRST robot.
Callin' 'em as I see 'em...
Joe J.
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Do you have any other information on the interaction between the inductance of the coils, and the commutor and the PWM switching? I find this interesting.