On Wed, 8 Jul 2009, Leslie Newell wrote: > Date: Wed, 08 Jul 2009 13:23:59 +0100 > From: Leslie Newell <les.new...@fastmail.co.uk> > Reply-To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Subject: Re: [Emc-users] Servo tuning > > I have just got the lathe on the internet so I uploaded a screen shot of > the I weirdness <http://imagebin.ca/view/Yh4hGxr.html>. It shows a long > move followed by the term returning the axis to position. The big spikes > are accel/decel. Here is a shot with the I term turned down to 0 but > everything else the same <http://imagebin.ca/view/3Uj1P_1.html>. I still > need to play around with the tuning to get rid of those acceleration > spikes. The accel is set very high at the moment for testing purposes. > > Les
IMHO you need to turn off I, and get the FE under control with P,D and FF1 before using I at all. adjusting FF1 should allow you to make the FE go either positive or negative as the velocity ramps up, you currently have a large negative FE, If this means motion is lagging, that means you need more FF1 The trick with FF1 and bare PWM amps is that you want FF1 set so that the PWM output voltage (BusV*PWM) = the motors BEMF at any velocity. Once the FE is under better control, I would bump up the I term so the response time of I is much faster, maybe .1 second or faster > > ------------------------------------------------------------------------------ > Enter the BlackBerry Developer Challenge > This is your chance to win up to $100,000 in prizes! For a limited time, > vendors submitting new applications to BlackBerry App World(TM) will have > the opportunity to enter the BlackBerry Developer Challenge. See full prize > details at: http://p.sf.net/sfu/Challenge > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your (")_(") signature to help him gain world domination. ------------------------------------------------------------------------------ Enter the BlackBerry Developer Challenge This is your chance to win up to $100,000 in prizes! For a limited time, vendors submitting new applications to BlackBerry App World(TM) will have the opportunity to enter the BlackBerry Developer Challenge. See full prize details at: http://p.sf.net/sfu/Challenge _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
