Doesn't even G02/G03 result in a series of very small linear moves sent to the servo motors? Wouldn't a NURB conversion do the same thing? On Apr 20, 2012 8:00 AM, "charles green" <xxzzb...@yahoo.com> wrote:
> another operation of the specialized gcode text editor: convert the > selected chunk of gcode/nurbs to a chunk of nurbs/gcode. > > i dont have a good idea of what a nurbs nc file might be like, but > whatever it is, it still has to result in more or less programmed machine > tool positions. the advantage in such case seems to be more in ease of > user manipulating the control code. at the machine level, the actuators > are going to move stepwise unless the whole spiel is somehow analog. > > so the question then is how to parse enormous sequences of linear steps > into code friendly sections. g1 is straitforward enough, but too slow > because the physical impementation involves inertia. g2/3 improves by > implying the g1 to g1 transitions within itself. > > would there be any advantage to making each physical machine axis into a > couple of circular movements, one going along R from 0 to 360 degrees while > the other rotates around 2R to make the motion linear? ..a rotary > differential movement instead of a linear movement. ..the arbitrary > interpolation schemes seem to be limited by the compliance character of the > machine movement. maybe the solution is a more fluid machine movement > somewhere beyond three orthogonal screws? > > > --- On Fri, 4/20/12, Viesturs Lācis <viesturs.la...@gmail.com> wrote: > > > From: Viesturs Lācis <viesturs.la...@gmail.com> > > Subject: Re: [Emc-users] Trajectory planning and other topics from a > EMC(LinuxCNC) newbie (TheNewbie) > > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net > > > > Date: Friday, April 20, 2012, 4:40 AM > > 2012/4/20 Michael Haberler <mai...@mah.priv.at>: > > > > > > to stay within that model, for instance the > > polyline-to-NURBS conversion would require yet another > > ad-hoce path 'queue'. The other option is to go the > > preprocessor route as Ken proposed. > > > > > > some problems cannot be addressed with a deeper > > interpretation-time path model like blending, which must be > > done at runtime due to external inputs like feed override > > which can impact on the actual path. > > > > > > > It seems like I did not express it in a proper way: > > My idea was to adjust Ken's suggestion with Nurbs. Basically > > it would > > be a filter, which would take g-code file with all the tiny > > G1 moves > > and return the same path, expressed with Nurbs. > > User then can save the output and reuse later. > > > > Michael, all the things You listed to be changed makes me > > think that > > filter is much easier to do (except the math part). > > > > 2012/4/20 charles green <xxzzb...@yahoo.com>: > > > wikipedia puts a somewhat different spin on nurbs. > > see the "use" section of the article, first paragraph. > > > > > > > Yes, I looked also at the "Construction of the basis > > functions" > > section and did not get much out of it. Well, I did get > > nothing out of > > it :)) > > > > Viesturs > > > > > ------------------------------------------------------------------------------ > > For Developers, A Lot Can Happen In A Second. > > Boundary is the first to Know...and Tell You. > > Monitor Your Applications in Ultra-Fine Resolution. Try it > > FREE! > > http://p.sf.net/sfu/Boundary-d2dvs2 > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > ------------------------------------------------------------------------------ > For Developers, A Lot Can Happen In A Second. > Boundary is the first to Know...and Tell You. > Monitor Your Applications in Ultra-Fine Resolution. Try it FREE! > http://p.sf.net/sfu/Boundary-d2dvs2 > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ For Developers, A Lot Can Happen In A Second. Boundary is the first to Know...and Tell You. Monitor Your Applications in Ultra-Fine Resolution. Try it FREE! http://p.sf.net/sfu/Boundary-d2dvs2 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
