On Tue, 21 Feb 2012, Anders Wallin wrote: > Date: Tue, 21 Feb 2012 14:43:34 +0200 > From: Anders Wallin <[email protected]> > Reply-To: EMC developers <[email protected]> > To: EMC developers <[email protected]> > Subject: [Emc-developers] Lookahead paper > > Trajectory control and lookahead seems to come up as a feature-request > periodically.. > I just found this recent paper which after a quick read-through looks > at least half-decent: > http://www.springerlink.com/content/k8613l2812153p65/ > If you don't have access drop me an email and I can send the PDF. > > To make progress on this one probably needs to restrict to 3-axis > trivkins, and maybe max feed-override <=100%. > In the near or not-so-near future I'd like to buy or setup a small > cnc-mill for various CAM experiments. If it can be built with high > feeds and accelerations (maybe 20m/min and 1g) then it might make > sense to work on improved trajectory control. > > Anders
The first page looks good... That does 'S' curve (Cubic) profiles which would improve accuracy for a given acceleration limit. S curves will reduce that last untunable following error spike at the beginning and end of a trapezoidal trajectory caused by a step function in the servo system force. Since S curves lower the high frequency components in the force input to the mechanics (Which is currently a step function as mentioned above), they also reduce exitation of mechanical resonances. > > ------------------------------------------------------------------------------ > Keep Your Developer Skills Current with LearnDevNow! > 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-d2d > _______________________________________________ > Emc-developers mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-developers > Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your (")_(") signature to help him gain world domination. ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! 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-d2d _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
