One thing to remember is the current linuxcnc trajectory planner seems to be rock solid. I don't remember someone having some odd motion that could not be explained. A lot of work/testing went into this.
sam On 09/13/2013 09:41 PM, Chris Morley wrote: > >> Date: Fri, 13 Sep 2013 14:54:04 -0500 >> From: [email protected] >> To: [email protected] >> Subject: [Emc-developers] Some trajectory testing between mach and linuxcnc >> >> I finally did it.. >> I installed mach3 on an xp machine and setup a machine. >> I setup linuxcnc and mach with all 3 axis set to 500ipm and 30 in/sec/sec. >> >> Well there you go.. It seems to be with strait G64 - linuxcnc 1 segment >> lookahead seems to be the limiting factor. There is some situations >> that the G64 Px.xxx will improve the path speed. (longer line segment >> means higher peak velocities.) This also suprised me - both mach and >> linuxcnc must be using very similar trajectory planning maths. >> >> High speed machining/routing/whatever with short line/arc segments is >> only possible at the moment with linuxcnc on high acceleration >> machines. (I had to set the acceleration to over 450in/sec/sec to get >> the velocitys up to 400ipm) >> >> In my opinion - this should be a priority. (and I know it is probably >> going to be a lot of work) (and about all I can do is test) >> >> Discuss... (of course I could be missing something obvious) (A work >> around perhaps?) >> >> sam > Hey Sam thanks for doing this and posting it to the maillist for everyone. > Finally a no assumptions comparison! > While I had no doubt the Mach guys weren't making it up, now we can > say yes you do have a faster feed on certain short segment Gcodes. > > I personally agree that this should be a higher priority feature. > And like you I don't know what this entails to actually do. > > I wonder if some one with linuxcnc trajectory experience could spell > out how this part of the trajectory planner works and what problems > /amount of work etc there would be to add look ahead. > > I think the fact that the trajectory planer is uncharted 'black magic' > that holds back it's further development. With some help maybe I could > start a current description in the wiki .... > > Chris M > > ------------------------------------------------------------------------------ > How ServiceNow helps IT people transform IT departments: > 1. Consolidate legacy IT systems to a single system of record for IT > 2. Standardize and globalize service processes across IT > 3. Implement zero-touch automation to replace manual, redundant tasks > http://pubads.g.doubleclick.net/gampad/clk?id=51271111&iu=/4140/ostg.clktrk > _______________________________________________ > Emc-developers mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-developers > ------------------------------------------------------------------------------ LIMITED TIME SALE - Full Year of Microsoft Training For Just $49.99! 1,500+ hours of tutorials including VisualStudio 2012, Windows 8, SharePoint 2013, SQL 2012, MVC 4, more. BEST VALUE: New Multi-Library Power Pack includes Mobile, Cloud, Java, and UX Design. Lowest price ever! Ends 9/22/13. http://pubads.g.doubleclick.net/gampad/clk?id=64545871&iu=/4140/ostg.clktrk _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
