On 02/03/2013 02:59 PM, EBo wrote: > On Feb 3 2013 1:02 PM, Chris Morley wrote: >>>> I don't know if the trajectory planner keeps the move history, if >>> it >>>> does then it might be possible to allow negative adaptive feed. >>> Unfortunately negative feed would require major rework - there is no >>> history of the path that has been executed. (That has also been >>> discussed at length in the context of EDM.) >>> >>> >>> -- >>> John Kasunich >>> jmkasun...@fastmail.fm >>> >> Michael did a proof of concept on jog-while-paused once. >> You can see it on Utube. >> >> I think it worked by making a second queue for the jogging part. >> Then when you were done it picked up the original queue's move. >> >> I wonder if that same basic concept could be put to use with >> backing up an EDM move. > possibly, but a more principled hack would be to interface it at the > point where it calls the low lever Catmull-Rom spline, and just evaluate > it in reverse. I do not know how difficult that would be, but it would > require the ability to move in the negitive direction. I have written > things like this for moving along splines with custom code, but I would > have to look into how to do this in EMC-s low level motion planning. > Probably the easiest thing to do would be to set up a "reverse-motion" > pin in HAL, and then evaluate it internally, or modify the adaptive move > command to allow positive/negitive feedback voltage which would imply > forward/reverse of motion. Anyway that is my thought off the cuff. > > EBo -- > > ------------------------------------------------------------------------------ > Everyone hates slow websites. So do we. > Make your web apps faster with AppDynamics > Download AppDynamics Lite for free today: > http://p.sf.net/sfu/appdyn_d2d_jan > _______________________________________________ > Emc-developers mailing list > Emc-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-developers looking at the catmull-rom spline, i see the curve is continuous ( tangential ) and should not require any blending at all in wedm for AGies we had a requirement for the paths to be tangential. in higher speed controls i can see this being an advantage ( less jerk )
tjtr33 ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_d2d_jan _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
