Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: mariod on August 10, 2012, 03:35:24 PM

Title: Dither
Post by: mariod on August 10, 2012, 03:35:24 PM

We get a lot of dither with an analog servo drive system using Mach 3.  When the system is idle, the DRO for the axis will dither by a few hundreds of a millimetre.  The output voltage to the drive is low, but present.  Is there any way to eliminate the dither.  It is like the PID is oscillating slightly.  Thanks.

Title: Re: Dither
Post by: Hood on August 10, 2012, 03:40:12 PM

What controller are you using?
It will either be a tuning issue or a controller issue  and not a Mach issue.
Hood

Title: Re: Dither
Post by: mariod on August 10, 2012, 03:45:21 PM

It is a DSPMC motion controller from Vital Systems.  The tuning is done on board this unit.  Do you think it is specific to this controller, or I have an issue with the PID parameters.

Title: Re: Dither
Post by: Hood on August 10, 2012, 03:47:06 PM

If the tuning is done in the DSPMC then that is where the problem lies I would say.
Hood