Read Velocity minimum threshold?

[RVallieu]

Is there a minimum velocity that an axis encoder must be above before the "Read Velocity.flx" will return a value?

When I run at slower speeds for the system and try to use this VI to determine the speed of the axis to calculate the appropriate time of the move, I am getting back 0 for my velocity.

Stepper motors, 5000 steps/revolution, 10 mm/rev pitch screw stages, 5000 counts/rev encoders.

Thank you,

Ryan

[VuD]

Hi Ryan,

If you look at the detailed help in LabVIEW for the "Read Velocity" VI, at the bottom of the document it says, "The data this VI returns is averaged based on parameters set in the Load Velocity Filter Parameter VI"  This VI configures the internal filter for velocity reporting. The reported velocity can oscillate due to feedback quantization error, noise, and jittery systems, etc. There is a lot more information given for this function in the detailed help that I would suggest looking at (update interval input, filter distance, etc).  I hope this helps.

Regards,

Vu