Thanks for the link to the documentation! I do plan to code this myself, though I would welcome any input from other developers. I'm sure many people have thought about this issue in the past and would have valuable input, especially on the implementation side.
Also, apologies in advance if this email formatting is butchered (copied from digest mode). Best, Rob > From: [email protected] > Date: Sat, 28 Sep 2013 15:31:41 -0400 > To: [email protected] > Subject: [Emc-developers] Proposing a Lookahead implementation for the EMC2 module > > Hi All, > I'm a grad student working on trajectory planning for robots. While > doing some fine-detail work using LinuxCNC on a mini-mill, I've bumped up > against the feed rate limitations due to small G-Code segments. Since this > kind of thing is my area, I wrote up a proposal to improve speed through a > longer queue and lookahead, linked here as a PDF: > > https://www.dropbox.com/s/p1g1zbwmviv5cn7/LinuxCNC%20Lookahead%20Proposal.pdf > > I'm obviously a bit of an outsider to emc development, so any feedback you > all have (positive or negative) would be greatly appreciated. > > Thanks! > Rob Hi Rob. Nice presentation and thanks for posting. While most of it is above my pay grade - I wanted to make sure you got a response. There are only a few developers with the experience to give pointed answers, hopefully they get a chance to answer. In a normal configuration the trajectory calculations are done at the servo thread speed, but this can actually be set to something else, previously it was often set to run ten times faster then the servo thread but that was found unnecessary. It's still in the docs : http://www.linuxcnc.org/docs/2.5/html/config/ini_config.html#_emcmot_section_a_id_sub_emcmot_section_a but most just set the servo thread and motmotion automatically sets the trajectory rate the same. So I would bet there is room to spend on optimization routines. Are you interested in actual coding these changes? lookahead is very much needed IMHO. Cheers Chris M ------------------------------------------------------------------------------ October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register > http://pubads.g.doubleclick.net/gampad/clk?id=60133471&iu=/4140/ostg.clktrk _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
