Servo direction
 

Hello

Do anybody now how to change the direction on a servo.

Regards
Finn
Denmark

Hello Finn,

a servo position is determined by the pulse width of the input signal. Direction of movement is determined by setting pulse width more wide or smaller.

regards Dirk

Hi Dirk

Thanks Dirk, but is it posibel to change someting in the servo to revers it?

Regards
Finn

Hi fmw,

it`s only an idea, but try to change the outer connections of the feedback poti inside of your servo unit. I guess this will cause a reverse function !

The other way could be to negate the input signal - this would certainly reverse all functions of your servo output mechanical gear. But i am sure this will be the more complicated way.....

regards


Peter

Hi fmw,

sorry, but i have to say that my last decision was completely wrong !
I tried to change the two outer poti connections at a big servo mechanism myself, and saw that there was a uncontrolled run into one end position as result.
It`s logic, because there is a fixed mechanical connection given by the gear, driving the feedback poti.
You would have to change both , the poti connections AND the motor polarity, but this would cause absolutely no change at all, the motor will turn exactly in same direction as before !

I guess the only methode to reverse such a servo system is to invert the pulse signal , coming into the servo-amplifier, or , if possible , to invert the polarity or voltage level of the input signal feeding the servo-pulser unit. This seems to be the easier way.


regards



Peter

Hi,

if this is a wish for an fsbus enhancement, a software solution is very easy. The values 0-255 have to be subtracted from 255 and that's all.
I think you will see this in next version.

regards Dirk

Hi Finn,

sometimes its better to think a bit longer and then answer a question. The solution is still inside fsbus.
Set Multiplier = -1, Offset = 255

Original value Calculated value
------------------------------------------
1 1*(-1)+255 254
10 10*(-1)+255 245
250 250*(-1)+255 5

This is your solution, isn't it ?

regards Dirk

Hi Dirk
:) :D :) :D :) :D :) :D :)

Your just great, this solve my problem, and it is function.

Thanks very much.

In few days, i will upload some picture of my instrument, how easy it is to make, by using some simpel parts from Simkit.

Regards
Finn