2011/10/13 andy pugh <bodge...@gmail.com>: > On 13 October 2011 10:33, Viesturs Lācis <viesturs.la...@gmail.com> wrote: > >> I have a special client, who does not understand, when I write in >> email and tell over the phone that no arc movements (G2/G3) will be >> executed in UV plane - I just received some complaints that machine is >> ruining parts, so I asked to send me the g-code file. Guess what did I >> see there... > > Is he using IJK or R?
IJK format is used. > I wonder how hard it is to make R work in UV when the UV plane is selected? > (I think that would be a better solution) Yes, this would do. The problem is that I have no idea, how to find that out. >> I would like to ask, if someone can recommend me a way, how I can >> relatively easily and quickly convert G2/G3 moves into small G1 moves. >> Well, any possible solution will do. > > Any filter would have the same problems as EMC2, how does it tell what > the customer intended? On my way to client I came up with a solution - transformation from polar coordinates to cartesian coordinates: 1) I have current tool position and from IJK I can derive center coordinates; 2) from IJK values I can easily calculate length of radius; 3) I need to know the starting angle and end angle - can be derived with atan2() function (current position - center position = value for atan2() function; 4) so now I have everything needed for polar coordinates - start angle, end angle and radius; 5) divide the angle in 1-3 degree increments; 6) convert polar to cartesian space: x=center + R*cos(a) y=center + R*sin(a) 7) since angle increments are equal, then all the small moves are of equal length. I wrote this in spreadsheet in ~15 minutes, not very convenient, but it is acceptable for manufacturing, where one particular part is produced in very large quantities without changes in code. > If this is the twin-head machine than I am not sure that they really > are UVW axes so much as alternative XYZ axes. Yes, that is a twin-head machine, which processes both ends of wood stick together. The problem is that for some products different profiles at each end are required. 2011/10/13 Chris Radek <ch...@timeguy.com>: > > I don't have any guess since if someone tried to write arcs in the > UV plane, it would just cause an error, not a ruined part. If tool is in X0 Y0 U0 V0 and there is a line G2 X50 Y50 U50 V50 I50 J0 Then XY will do the arc, but UV will do a straight line to the end point. > What kind of motion are you talking about? Just plain simple arcs in > UV, or some kind of complicated combined motion where UV does one > thing while XY does another? Second option would be the ideal solution, because the machine has to process both ends of material simultaneously. Plain simple arcs in UV also would be a step forward from current situation - then at least there would be option to process XY end and after that UV end - I already know that client would object that it is a waste of time and thus increased cost, but at least there would be some options. The problem with my "divide arcs in small linear moves" approach is that it is too slow, linear moves are too short to reach the required speed even when with G64 P0.1 (that is max deviance acceptable), the tool burns material, so the whole approach is a failure. What I ended up with: Custom pseudokinematics - with use of mux2 components, operator can switch joints 6 and 7 from U and V to X and Y respectively - for those parts, where both ends are the same, they can do all the G2/G3 moves. For those parts, where profiles at both ends are not the same - it is a problem yet to be solved. Thanks, Thomas! I took a look and it seemed to me that they are trying to do something different than that - I also do not speak German (and unfortunately translate tool in Chrome does not offer to translate the contents) they are doing kinematics calcs, where the tool is moved by two wires: http://code.google.com/p/emc2hotwinch/downloads/detail?name=Geometrie.JPG Dave, the idea was to use existing g-code with G2/G3 moves, but as I mentioned, that approach failed. So the question is - how hard would that be to get G2/G3 support for UV plane? It would not matter, if that is IJK format or R format. Viesturs ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity and more. Splunk takes this data and makes sense of it. Business sense. IT sense. Common sense. http://p.sf.net/sfu/splunk-d2d-oct _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
