I think the error of this approach (using N times higher accel/vel) is coming from the piecewise linear approximations of the curves going bad. If you try to follow a curve N times faster, then there are N times fewer samples along that curve for a fixed time sampling period. That introduces errors. There may be others but thats at least part of it. Its the same problem w/ discrete time vs continuous time systems. There is divergence between the solutions as the sampling rate goes down.
On Thu, Oct 13, 2016 at 3:08 PM, Todd Zuercher <zuerc...@embarqmail.com> wrote: > I was just working at this a little bit. The first thing I did was to > modify time.comp, to make a new sim_time.comp. The sim_time.comp is > basically just the same as the regular timer component with an input pin > added to scale the time to what ever factor you speed up the simulation > run. Then I made a dummy config of one of our machines with all the > velocities and accelerations increased by 1000x, and test ran a few things, > the results were not quite as good as I had hoped, but were way better than > the old estimations. Is it possible that some of the inaccuracy came from > the fact I was running it in a VM? > > The timer scaling pin was a really simple mod, would there be any interest > in adding that to the regular release? > > ----- Original Message ----- > From: dan...@austin.rr.com > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Sent: Thursday, October 13, 2016 2:24:53 PM > Subject: Re: [Emc-users] Hacking a sim runtime mode > > > ---- Chris Albertson <albertson.ch...@gmail.com> wrote: > > On Thu, Oct 13, 2016 at 9:00 AM, Peter C. Wallace <p...@mesanet.com> > wrote: > > > On Thu, 13 Oct 2016, dan...@austin.rr.com wrote: > > > > > > > > I just tried a real time Mesa Ethernet config with maxvel = 120000 IPM > (2000 > > > IPS = 20 MHz step rate at present 10000 steps/In scaling) and maxaccel > 20000 > > > IPS/S (52 Gs) with a 1 KHz servo thread, and it works fine (Peak > following > > > errors in the 1-2 mill region) > > > > The problem to be solved is getting an estimate of the time required > > to complete a job. Does the above do this accurately? > > Yeah I want to know this. I can run a job for real vs "fast sim" and > compare. One prob is the cycle time only goes down to seconds AFAIK. If > it's 100x then that's over a minute and a half it could be wrong, but > that's still good enough as long as it's not estimating a very short job. > > ------------------------------------------------------------ > ------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users