servo speeds

Archiver

Hello,
I built a light tracking device, but am having a problem with the speed of
the servo motor used.
I want the servo to move slow enough to follow a flashlight beam back and
forth at various speeds, but the servo is just jolting back and forth very
fast. Any suggestions?
Thanks alot.
Mike

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Archiver

Mike:

I did something similar to this and to avoid the "jerking" I make loops
with the position value "walking" to the target value returned by the
light sensor.

Rather than directly changing the PWM parameter that controlled the
stepper to the new reading returned from the light sensor, I would
compare the sensor reading to the current position and, if different, I
would "walk" the value up or down from the existing value by entering a
decrement or increment loop until the old value matches the new value.

Also, you can set a bit of slop in there to keep the unit from seeking
when the servo is very close to the correct target postion. Worked pretty
well for me.. [noparse]:)[/noparse]

Vern

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Mike Kohl said:
> Hello,
> I built a light tracking device, but am having a problem with the speed
> of
> the servo motor used.
> I want the servo to move slow enough to follow a flashlight beam back and
> forth at various speeds, but the servo is just jolting back and forth
> very
> fast. Any suggestions?
> Thanks alot.
> Mike
>
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