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View Full Version : Labview servo motor PWM correlation to set VI


mbone206
29-01-2009, 17:56
The Servo SetVI is '0 to 1'

PWM VIs, 0 to 255 where 1 is full reverse and 255 is full foward

How does Servo '0 to 1' scale with PWM '0 to 255'

Example: If I read back 127 on servo motor using PWM-GetValue VI, what ould be the '0 - 1' position of Servo

new at this, thank you for your patience and support

Luke Pike
29-01-2009, 21:50
I'm not sure what your asking, but here's some info. Servos can get or set angle or position. Angle should be between 0 and 180.

It seems like your using the PWM vi's to set the value? You can set the angle or the position of a servo using the Set Angle and Set Position vi's.

ebmonon36
29-01-2009, 23:48
0=127 - One end of the rotation
1=255 - The other end of rotation.
Any number in between 0 and 1 would be a position between the stops on the servo. 0.5 would be half way.

mbone206
30-01-2009, 13:02
ebomnon - 36 - got it - thanx

Kevin Sevcik
30-01-2009, 14:58
0=127 - One end of the rotation
1=255 - The other end of rotation.
Any number in between 0 and 1 would be a position between the stops on the servo. 0.5 would be half way.
This is incorrect. Please bother to actually to do some research on a question before you answer it.

The correct answer is that a 0 to 1 range on the input of a Servo:SetPosition.vi corresponds to an 11 to 253 range of actual PWM values. So in your parlance:
0.0 = 11 One end of rotation
1.0 = 253 The other end of rotation

You can discover this by simply opening up some of the associated VIs. You may even learn something in the process.