Hey Robert, Have you had a chance to look at this any closer? We hit this error 100% of the time on the Pocket NC for specific values of various HOME_OFFSETs (our current solution is to tweak those values by .0001" until the error goes away). The error occurs immediately after pressing the run button on any program after homing the machine. Any jogging before running the program and it runs fine. I've done a little digging into the code base to see what could be causing the issue, but don't have a good enough sense of the overall flow of data. Any insights would be appreciated. I've located several floating point equality comparisons that would result in a more precise comparison than the 1e-20 the trajectory planner is comparing against, but haven't had any luck when changing from direct equality (or inequality) operations to a difference comparison (i.e. changing x == y to abs(x-y) < epsilon).
Here are a few places I've tried adjusting: https://github.com/machinekit/machinekit/blob/1dfa0045ba95fd68e744826d684efa513cbffa97/src/emc/motion/control.c#L449 https://github.com/machinekit/machinekit/blob/1dfa0045ba95fd68e744826d684efa513cbffa97/src/emc/rs274ngc/interp_convert.cc#L2465 (and several other similar instances in that same file) https://github.com/machinekit/machinekit/blob/1dfa0045ba95fd68e744826d684efa513cbffa97/src/emc/nml_intf/canon_position.cc#L73 (as well as !=) I don't know the best way to go about debugging this. Do you know how I could find where the zero length moves are being added to the trajectory planner and what normally prevents that from happening? Yours and Schooner's insights have been helpful so far. Maybe we can work together to figure out what is going on. -John On Saturday, February 25, 2017 at 1:16:32 PM UTC-7, Robert Ellenberg wrote: > > Hi All, > > My guess is that this is a mismatch between canon and the TP in how a zero > length segment is defined. I recall running into a similar issue with > LinuxCNC. If we're lucky, it's been fixed already in another branch and > it's a matter of porting the fix over to Machinekit. I'll take a look this > weekend. > > Best, > Rob > > On Sat, Feb 25, 2017 at 10:08 AM [email protected] <javascript:> < > [email protected] <javascript:>> wrote: > >> >> On 25/02/17 11:47, [email protected] <javascript:> wrote: >> >> >> On 25/02/17 07:55, icecube45 wrote: >> >> It's seemingly a different line each time I run the file, this time it >> was line 20462, which is either the middle of >> >>> G1 X-9.794 Y-69.769 A29.4549 >>> >>> G1 X-10.971 Y-71.809 A29.5489 >>> >>> G1 X-13.951 Y-71.809 A29.6678 >>> >>> or the middle of >> >>> >> >> G1 X31.776 Y-64.609 A48.9986 >> >> G1 X34.755 Y-64.609 A49.1175 >> >> G1 X35.933 Y-62.569 A49.2115 >> >> >> defendant on if comments count as lines or not.. >> Nothing seems out of the ordinary here, which is why I'm so confused. >> >> >> The error is defined as TP_ERR_ZERO_LENGTH >> >> https://github.com/machinekit/machinekit/blob/master/src/emc/tp/tp_types.h#L61 >> >> The trajectory planner is dark magic with which I have no particular >> familiarity. >> It was certainly not developed to squirt plastic in tens of thousands of >> extremely small moves. >> >> My only guess might be that depending upon what blending settings you >> have, it may not recognise a commanded move(s) as >> any sort of move at all. >> But I could be completely wrong. >> >> Hopefully Robert or someone with more knowledge will chime in. >> >> >> Just to flesh this out a bit >> >> This is the code which is throwing the error >> https://github.com/machinekit/machinekit/blob/master/src/emc/tp/tp.c#L1937 >> >> if (tc.target < TP_POS_EPSILON) { >> rtapi_print_msg(RTAPI_MSG_DBG,"failed to create line id %d, >> zero-length segment\n",tp->nextId); >> return TP_ERR_ZERO_LENGTH; >> } >> >> If you switched on debugging, you should see this message in >> /var/log/linuxcnc.log >> >> This is why I am surmising that an extremely small move, with some >> rounding down from the tp settings, >> could be causing the error. >> >> TP_POS_EPSILON is defined here >> >> https://github.com/machinekit/machinekit/blob/master/src/emc/tp/tp_types.h#L44 >> as 1e-12 ( which is 10 to -12 or 0.000 000 000 001 !! ) >> >> Why this is occurring I don't know, but you can switch on debugging and >> confirm that this is indeed the bit causing it. >> >> You can also switch off blending (G64 P0) or adjust the blend tolerance >> settings ( G64 Pn.nn ) and see if it improves. >> >> >> >> >> On Friday, February 24, 2017 at 4:47:47 AM UTC-8, Schooner wrote: >>> >>> >>> On 24/02/17 12:03, icecube45 wrote: >>> >>> Does anyone have any idea what this error code is? It occasionally >>> happens, yet I can't isolate what is actually causing it, nor what the -7 >>> error code actually means. >>> >>> >>> >>> https://github.com/machinekit/machinekit/blob/master/src/emc/motion/command.c#L953 >>> >>> It means that it does not like one of the parameters to a linear move. >>> >>> EMCMOT_COMMAND_BAD_EXEC means there was an error trying to initiate the >>> command. >>> This would suggest the command was valid syntax but the acc, vel, move >>> extent or some other factor was not. >>> >>> Unless you can tell us what the move asked for was, it is impossible to >>> guess. >>> >>> line xxxx should be a number, it may not strictly equate to the line >>> number but should be a number non the less. >>> >>> >>> >>> I'd appreciate any advice on how to fix this error - it's popping up >>> randomly and stopping my prints. >>> >>> For reference, I'm on a BeBoPr++ lineardelta configuration. >>> -- >>> website: http://www.machinekit.io blog: http://blog.machinekit.io >>> github: https://github.com/machinekit >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "Machinekit" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> Visit this group at https://groups.google.com/group/machinekit. >>> For more options, visit https://groups.google.com/d/optout. >>> >>> >>> -- >> website: http://www.machinekit.io blog: http://blog.machinekit.io >> github: https://github.com/machinekit >> --- >> You received this message because you are subscribed to the Google Groups >> "Machinekit" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> Visit this group at https://groups.google.com/group/machinekit. >> For more options, visit https://groups.google.com/d/optout. >> >> >> -- >> website: http://www.machinekit.io blog: http://blog.machinekit.io >> github: https://github.com/machinekit >> --- >> You received this message because you are subscribed to the Google Groups >> "Machinekit" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> Visit this group at https://groups.google.com/group/machinekit. >> For more options, visit https://groups.google.com/d/optout. >> >> >> -- >> website: http://www.machinekit.io blog: http://blog.machinekit.io >> github: https://github.com/machinekit >> --- >> You received this message because you are subscribed to the Google Groups >> "Machinekit" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> Visit this group at https://groups.google.com/group/machinekit. >> For more options, visit https://groups.google.com/d/optout. >> > -- website: http://www.machinekit.io blog: http://blog.machinekit.io github: https://github.com/machinekit --- You received this message because you are subscribed to the Google Groups "Machinekit" group. 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