On 1/27/2012 2:54 PM, Peter C. Wallace wrote: > On Fri, 27 Jan 2012, Viesturs L?cis wrote: > >> Date: Fri, 27 Jan 2012 21:58:27 +0200 >> From: "[UTF-8] Viesturs L?cis" <[email protected]> >> Reply-To: "Enhanced Machine Controller (EMC)" >> <[email protected]> >> To: "Enhanced Machine Controller (EMC)" >> <[email protected]> >> Subject: Re: [Emc-users] Servo tuning - wtf? >> >> 2012/1/27 Peter C. Wallace <[email protected]>: >>> On Fri, 27 Jan 2012, Viesturs L?cis wrote: >>> >>>> Date: Fri, 27 Jan 2012 21:49:18 +0200 >>>> From: "[UTF-8] Viesturs L?cis" <[email protected]> >>>> Reply-To: "Enhanced Machine Controller (EMC)" >>>> <[email protected]> >>>> To: "Enhanced Machine Controller (EMC)" >>>> <[email protected]> >>>> Subject: Re: [Emc-users] Servo tuning - wtf? >>>> >>>> Hello again! >>>> >>>> I tried searching my mailbox with more than 2 years of this mailing >>>> list in it for some "servo tuning for noobs" (actual keywords used >>>> were "servo tuning"), but found only 1 viable thread, which contained >>>> this link; >>>> http://www.newport.com/servicesupport/Tutorials/default.aspx?id=152 >>>> >>>> My problem is: >>>> I can tune servo motor to move smoothly up to ~3600 mm/min, which is >>>> ~1500 RPM for motor. >>>> In higher speeds at one moment motor stalls and oscillates. >>>> Where can I read, how to proceed to reach higher velocities? >>>> I have been playing with P and D parameters, but do not see any >>>> improvement. >>>> >>>> Viesturs >>> >>> >>> Whats is your servo thread period, and how many poles does the motor >>> have? >>> >> >> Servo period is default 1ms. >> Motors have 4 poles, motors have 2048 CPR (8192 >> PPR) encoders. >> >> Viesturs > > What BLDC mode are you using? > > When it fails and oscillates does the motor behave normally when > stopped (equal torque both directions)? > > If not you may somehow have lost encoder counts, this should be checked > > Do you have the encoder filter on? > > > Peter Wallace > Mesa Electronics Peter:
I think your system clock is off. Your replies to Viesturs' messages are arriving here with time stamps roughly 4 minutes before the time stamps on the messages you are replying to. A quick look at the message headers suggests the problem is at your end and not his (but I've been wrong before). In the grand scheme of things this doesn't much matter but since my mail agents sorts incoming mail on the time stamp, I read your response before I see the question. It was a bit disconcerting the first time. On the other hand, if it's a real effect, you've found a way to communicate faster than the speed of light and with an effect way bigger than the billionths of a second that the folks at CERN and Gran Sasso Laboratory were reporting. I smell a Nobel Prize in the offing. Regards, Kent ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
