I did a quick test - Doesn't run full speed now. There are some spikes (if I have the MV slider set to 20ipm - I see spikes to 20.7) I don't know if it is an issue or not. (I don't think it would bother me..)
http://imagebin.org/302238 sam On 03/27/2014 09:36 PM, Robert Ellenberg wrote: > Good catch! It wasn't checking the slider max velocity (tp.vLimit) when > doing ramped velocity, so those sections ran at full speed. The latest push > to the RC3 branch should fix that. > > > On Thu, Mar 27, 2014 at 9:59 PM, sam sokolik <sa...@empirescreen.com> wrote: > >> here is a video showing the jumping of the velocity. (we cobbled >> together an old terco trainer to play with) >> >> http://www.youtube.com/watch?v=4Mz7tzVSsYk&feature=youtu.be >> >> here is the little machine running the penguin as fast as it can go.. >> (with the setting we had) it seems go gain z hight (about .030 each >> run) - but our wiring is so bad that I am surprised it works as good as >> it does. >> >> http://www.youtube.com/watch?v=Qp0ZpxsgxVs >> >> The new tp ran the penguin in 1:40 vs 2:20. (lots of strait lines that >> run the same with both planners) >> >> sam >> >> On 03/27/2014 05:48 PM, sa...@empirescreen.com wrote: >>> one more thing - maximum velocity slider doesn't seem to be obeyed. >> some of the time it is - but take the 3dchips and have the feedrate set >> very high. now run the maximum velocity slider to say 10 ipm. when it >> gets to sections of short line segments - it take off and goes at a much >> higher feedrate.. >>> sam >>> >>> >>> On Wed, 26 Mar 2014 15:03:50 -0500 >>> sam sokolik <sa...@empirescreen.com> wrote: >>>> here is 50% (1750mm/min) >>>> >>>> http://imagebin.org/301967 >>>> >>>> sam >>>> >>>> >>>> On 03/26/2014 02:49 PM, Robert Ellenberg wrote: >>>>>> One thing I noticed... Lets say we are running that profile at >> 3500mm/s >>>>>> and it is dipping like this http://imagebin.org/301375 if you slow >> the >>>>>> feedrate down - the dips get scaled also. I would think at 3200mm/min >>>>>> it would flatten out. :) (probably another nit-pick) >>>>> That's a good point, it shouldn't scale proportionally at lower feeds. >> Does >>>>> that keep happening at slower feeds like 3000 or 2500? If so, it might >> mean >>>>> that something's being limited that doesn't need to be. >>>>> >>>>> -Rob >>>>> >>>>> >>>>>> sam >>>>>> >>>>>> On 3/26/2014 1:27 PM, Robert Ellenberg wrote: >>>>>>> Hi Sam, >>>>>>> >>>>>>> This acceleration limitation is by design, so that the TP can deal >> with >>>>>>> tangential and normal acceleration separately. On a circular arc >> segment, >>>>>>> the acceleration along the path is limited to 0.5 * a_max. Using the >>>>>>> pythagorean theorem, the maximum normal acceleration is: >>>>>>> >>>>>>> sqrt( a_max^2 - (1/2*a_max) ^2 ) = sqrt(3/2) * a_max ~= .866 * a_max >>>>>>> >>>>>>> So, if your maximum axis acceleration is 30 in/sec^2, then the TP >> only >>>>>>> moves fast enough around the arc to create 25.98 in/sec^2 of normal >>>>>>> acceleration. This way, if you have to speed up or slow down during >> an >>>>>> arc >>>>>>> move, the total acceleration it won't exceed the machine maximum. >>>>>>> >>>>>>> A good analogy is high-speed cornering with a car on a twisty road. >>>>>> There's >>>>>>> a maximum speed you can go around the corner before the tires slip. >>>>>>> However, if you actually drive at that speed and have to hit the >> brakes, >>>>>>> you're in trouble :). So, to be safe, you go a little slower so that >> you >>>>>>> can slow down if need be. >>>>>>> >>>>>>> The good news is, this particular limit on tangential vs. cornering >>>>>>> acceleration gets you pretty close to top speed. For example, on a >> 0.1" >>>>>>> radius, a max normal acceleration of 26 in/sec^2 gives you a max >> speed of >>>>>>> sqrt( 26 in/sec^2 * 0.1 in) ~= 1.61 in/sec. Compare that to 30 >> in/sec^2, >>>>>>> which gives you sqrt( 30 in/sec^2 * 0.1 in) ~= 1.73 in/sec (about 7% >>>>>>> difference). >>>>>>> >>>>>>> I just hard-coded this because it seemed to give me the best speed >> on my >>>>>>> test runs. Maybe it could be an INI parameter? You could potentially >> get >>>>>> a >>>>>>> little performance from a program with lots of circular arcs by >> reducing >>>>>>> the tangential acceleration in favor of normal acceleration. >> Conversely, >>>>>>> making tangential and normal acceleration both sqrt(2) * a_max might >> move >>>>>>> more quickly in programs with a lot of detail like stellabee1.ngc. >>>>>>> >>>>>>> -Rob >>>>>>> >>>>>>> On Mon, Mar 24, 2014 at 2:47 PM, sam sokolik <sa...@empirescreen.com >>>>>> wrote: >>>>>>>> I have a question about the acceleration limits. (and I might be >>>>>>>> nit-picking here) But I have been goofing around with the >>>>>>>> trochoidal.ngc file from >> http://www.vagrearg.org/gcmc/trochoidal.ngc.gz >>>>>>>> I see when I push the velocity up to 3500mm/min - the peak velocity >>>>>>>> starts to dip (this is with 30in/s^2 acc) >>>>>>>> >>>>>>>> http://imagebin.org/301375 >>>>>>>> >>>>>>>> but you can see that the acc doesn't get to 30in/s^2 - it seems to >> peak >>>>>>>> at about 26 or so. I did play around with the gap freq in the ini >> file >>>>>>>> (setting it to my servo period of 1000) and it may have helped just >> a >>>>>>>> little bit. >>>>>>>> >>>>>>>> http://imagebin.org/301376 (acc peaks just a little higher) >>>>>>>> >>>>>>>> is this just a limitation of the whole system? It it still way way >>>>>>>> better than the current tp - but was wondering what was causing >> this. >>>>>>>> sam >>>>>>>> >>>>>>>> >> ------------------------------------------------------------------------------ >>>>>>> Learn Graph Databases - Download FREE O'Reilly Book >>>>>>> "Graph Databases" is the definitive new guide to graph databases and >>>>>> their >>>>>>> applications. Written by three acclaimed leaders in the field, >>>>>>> this first edition is now available. Download your free book today! >>>>>>> http://p.sf.net/sfu/13534_NeoTech >>>>>>> _______________________________________________ >>>>>>> Emc-developers mailing list >>>>>>> Emc-developers@lists.sourceforge.net >>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-developers >>>>>>> >>>>>>> >>>>>> >> ------------------------------------------------------------------------------ >>>>>> Learn Graph Databases - Download FREE O'Reilly Book >>>>>> "Graph Databases" is the definitive new guide to graph databases and >> their >>>>>> applications. Written by three acclaimed leaders in the field, >>>>>> this first edition is now available. Download your free book today! >>>>>> http://p.sf.net/sfu/13534_NeoTech >>>>>> _______________________________________________ >>>>>> Emc-developers mailing list >>>>>> Emc-developers@lists.sourceforge.net >>>>>> https://lists.sourceforge.net/lists/listinfo/emc-developers >>>>>> >> ------------------------------------------------------------------------------ >>>>> Learn Graph Databases - Download FREE O'Reilly Book >>>>> "Graph Databases" is the definitive new guide to graph databases and >> their >>>>> applications. Written by three acclaimed leaders in the field, >>>>> this first edition is now available. Download your free book today! >>>>> http://p.sf.net/sfu/13534_NeoTech >>>>> _______________________________________________ >>>>> Emc-developers mailing list >>>>> Emc-developers@lists.sourceforge.net >>>>> https://lists.sourceforge.net/lists/listinfo/emc-developers >>>>> >>>> >> ------------------------------------------------------------------------------ >>>> Learn Graph Databases - Download FREE O'Reilly Book >>>> "Graph Databases" is the definitive new guide to graph databases and >> their >>>> applications. Written by three acclaimed leaders in the field, >>>> this first edition is now available. Download your free book today! >>>> http://p.sf.net/sfu/13534_NeoTech >>>> _______________________________________________ >>>> Emc-developers mailing list >>>> Emc-developers@lists.sourceforge.net >>>> https://lists.sourceforge.net/lists/listinfo/emc-developers >>> >> ------------------------------------------------------------------------------ >>> _______________________________________________ >>> Emc-developers mailing list >>> Emc-developers@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/emc-developers >>> >> >> >> ------------------------------------------------------------------------------ >> _______________________________________________ >> Emc-developers mailing list >> Emc-developers@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-developers >> > ------------------------------------------------------------------------------ > _______________________________________________ > Emc-developers mailing list > Emc-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-developers > ------------------------------------------------------------------------------ _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
