| slacker 2007-08-31, 9:25 pm |
| To me it does not make sense to talk about PID and stepper motors
because as you mentioned, the contrasting continuous and discrete states
of the two.
PID generates and error voltage to feed into the motor, which won't
drive a stepper motor. Perhaps there is an algorithm/circuit to convert
between the two for application but I can't see why there would be.
Stepper motors are designed for high speed/accuracy servo applications,
not high loads (which PID and a bigger DC/AC motor would be better
suited for).
simnav@gmail.com wrote:
> Sorry.. I've forgotten this question in previous message: It's
> possible to control a stepper motor in a closed loop system via a
> common PID algorithm ? I ask this to you because many commercial
> controllers that I've found have encoder input but use it only for
> stall detection. I think a continuous controlling of stepper motor
> isn't a great idea due to discreet nature and relative low resulution
> of stepper motors: I think that is sufficient an accidental little
> movement of mechanical system respect to idle position to cause
> continuous vibrations: is it correct ? My idea is to use PID only
> during motion commands and stop it when axis is settled in a given
> range: it will limits axis overshoot and precise positioning without
> undesidered steady vibrations.
> What do you think about.
>
> Best regards.
> Simone Navari.
>
|