Hi to all. Just to show an amazing sewing technology . Robot Sewing Machine <https://www.youtube.com/watch?v=_i4cfQGe8fY> I do believe that in this case a synchronicity between robot axis and needle position is needed.
Regards Alex On Fri, Aug 29, 2014 at 6:04 PM, alex chiosso <[email protected]> wrote: > Hi Gregg. > Yes this device should be fast enough. > The problem is how to integrate it with the current machanic structure. > You have to consider also that the operator need the right space where to > lay the fabric (i.e. the jacket). > > Regards > > Alex > > > On Fri, Aug 29, 2014 at 5:29 PM, alex chiosso <[email protected]> wrote: > >> Hio Philipp , >> you got it! >> The exact lenght for each stitch is a must. >> So the example of G code that you kindly gave me is what should be done >> (I mean it is a starting point) . >> Actually (I was this morning to the sewing machine customer) with the >> intergration I did the result is good enough for what they have to do (an >> Hybrid solution PLC+Position controller single axis modules) . >> But because of a stitch by stitch X-Y axis movement and the speed as fast >> as possible the machine has some vibrations that the customer would be >> happy to reduce as much as possible. >> The integration I made as some limitatons related to the way the fabric >> is moved under the needle between a stitch and the following one . >> Secondary only linear stitches are possible because no interpolation is >> possible due to the hardware/software used. >> So I do believe that a solution with LCNC can make a smoothest movement >> of the machine , the possibility to do different kinds of stitches and a >> more flexible pattern design . >> At the moment the customer told me that this machine is quite "unique" >> because is able to apply labels on dresses that are already fabricated >> (finished ready for the delivery) . >> That is why the label sewing must be done without error on the axes >> movements that can damage the needle and consequently the tissue. >> The dresses are high end quality (and costly) Italian made . (I'm Italian >> .... that's why my english writing style is so poor!) >> Other machines can only apply labels on semifinish parts of the dresses >> and the potential risk is less important . >> I saw a similar G code on a Mach3 forum somewhere on the net but I didn't >> see any final result onestly . >> That's amazing to see that many people are trying to apply a CNC to do >> sewing/embroidery/quilting machine conversion. >> For sure for complex pattern design a sort of cad/cam is needed. >> I was wondering if a programming style with iterative sequences (one >> iteration one stich) can help for not complicated pattern. >> In any case thank you for any idea/thought you are sharing. >> >> Regards >> >> Alex >> >> >> >> >> On Thu, Aug 28, 2014 at 10:14 PM, Philipp Burch <[email protected]> wrote: >> >>> Hi Alex! >>> >>> On 27.08.2014 22:04, alex chiosso wrote: >>> > Hi Philipp. >>> > Thank you so much for the very detailed informations . >>> > You are considering to move the needle as a spindle with the S >>> parameter to >>> > define the rpm and the >>> >>> Exactly. >>> >>> > Z axis position how is it derived from ? How is it calculated ? I mean >>> on >>> > the real machine . >>> >>> This is what the siggen component in the example HAL file is used for. >>> The spindle speed (i.e. stitches per second) is fed to its frequency >>> input as well as the desired amplitude (the full Z travel of the >>> needle). The component then generates a free running sine wave (among >>> other waveforms) of the requested frequency. You would then use this >>> wave as the position setpoint for the Z axis motor controller. No need >>> to calculate anything else ;) >>> >>> Somewhat later, you told us that it is required that the X/Y movement >>> always needs to completely finish before making the next stitch for a >>> constant stitch length. If you use the approach described before, you >>> won't have the ultimate control, so depending on your hardware, you >>> could really end up with stitches that are of slightly different >>> lengths. If this actually is a problem, you might be better off using >>> the Z axis as usual and describing every single stitch in your NC >>> program like so: >>> >>> G21 (Millimeters) >>> G64 P1 Q1 (Path tolerance 2mm) >>> G0 Z5 (Safe needle height) >>> G0 X10 Y10 (Position of first stitch) >>> F5000 (Feed rate for all subsequent moves) >>> G1 Z-5 (Enter fabric, which is at Z = 0) >>> G1 Z1 (Exit fabric) >>> G1 X12 Y10 Z5 (Move to midpoint to next stitch) >>> G1 X14 Y10 Z1 (Move to next stitch) >>> G1 Z-5 (Enter fabric) >>> G1 Z1 (Exit fabric) >>> G1 X16 Y10 Z5 (Move to midpoint to next stitch) >>> G1 X18 Y10 Z1 (Move to next stitch) >>> G1 Z-5 (Enter fabric) >>> G1 Z1 (Exit fabric) >>> ;... >>> G0 Z5 (Safe needle height) >>> G0 X0 Y0 (Move to park position) >>> M2 >>> >>> As you can see with all those G1s, the program gets much more >>> complicated and veeery inconvenient to write by hand. So you'd most >>> likely want to use a CAM (or just a python script), which generates this >>> structure. >>> >>> The setting of the path tolerance is required to get a reasonable speed. >>> The programmed path contains vertical segments for entering and exiting >>> the fabric and a triangular curve from one stitch to the next. If the >>> needle would need to follow this path exactly, the whole thing would be >>> slow like hell of course, so we give the trajectory planner some >>> tolerance by which the actual path may differ from the programmed path. >>> What then happens is that the actual path has arcs instead of sharp >>> edges, which helps to keep the speed up. Please see the attached >>> screenshot. The white line is the programmed path, the red one is the >>> backplot of the simulated machine movement. >>> >>> I hope this helps. >>> >>> Cheers, >>> Philipp >>> >>> > On Wed, Aug 27, 2014 at 9:34 PM, Philipp Burch <[email protected]> wrote: >>> > >>> >> Hi Alex! >>> >> >>> >> On 27.08.2014 21:13, alex chiosso wrote: >>> >>> Hi Andy. >>> >>> You are always a good advisor . >>> >>> I'm not so trained on LCNC as you are. >>> >>> I never use the lincurve component so can you explain me what it is >>> and >>> >> how >>> >>> it works ? >>> >>> Also Philipp mention the adaptive pin but I didn't understand that >>> he was >>> >>> referring to the motion component of LCNC. >>> >> >>> >> The lincurve component performs interpolation using a function >>> >> consisting of linear segments. So if your machine may move while the >>> >> needle position is >3.0, then you could for example create an >>> >> interpolation function with two segments: >>> >> >>> >> For Z = 3.0 .. 7.0, ramp up the feed linearly from 0 to F-max >>> >> For Z = 7.0 .. MAX, keep the feed at F-max >>> >> >>> >> By adding additional segments, you could then control the feed more >>> >> smoothly during the movement of the needle. >>> >> >>> >> The adaptive feed is an input of the motion component, which can >>> modify >>> >> the feed rate in real time. In my example, I used feed-hold, which >>> just >>> >> forces the feed to 0, accounting only for the acceleration limits of >>> the >>> >> machine. By using adaptive feed, you can insert a custom ramp (or >>> >> whatever the curve's shape should be). So it would also be possible to >>> >> use a cosine curve for the feed or something like this instead of a >>> >> trapezoidal one like in the example. It might be worth some >>> >> consideration if you need to limit jerk, as this could easily become a >>> >> problem on such a machine. >>> >> >>> >> Regards, >>> >> Philipp >>> >> >>> >>> >>> >>> >>> >>> On Wed, Aug 27, 2014 at 9:00 PM, andy pugh <[email protected]> >>> wrote: >>> >>> >>> >>>> On 27 August 2014 16:21, alex chiosso <[email protected]> wrote: >>> >>>>> I would like to discuss with you what do you think about the >>> conversion >>> >>>> to >>> >>>>> LCNC. >>> >>>> >>> >>>> One very easy way (maybe too easy) would be to pass needle height >>> >>>> through a lincurve component (I use that for nearly everything, >>> >>>> because we use them for nearly everything in the day job) and then >>> use >>> >>>> the output to drive the motion.adaptive-feed pin. You can then >>> define >>> >>>> zones where movement is possible and have a gentle decel up to those >>> >>>> zones defined in the curve shape. >>> >>>> >>> >>>> -- >>> >>>> atp >>> >>>> If you can't fix it, you don't own it. >>> >>>> http://www.ifixit.com/Manifesto >>> >>>> >>> >>>> >>> >>>> >>> >> >>> ------------------------------------------------------------------------------ >>> >>>> Slashdot TV. >>> >>>> Video for Nerds. Stuff that matters. >>> >>>> http://tv.slashdot.org/ >>> >>>> _______________________________________________ >>> >>>> Emc-users mailing list >>> >>>> [email protected] >>> >>>> https://lists.sourceforge.net/lists/listinfo/emc-users >>> >>>> >>> >>> >>> >> >>> ------------------------------------------------------------------------------ >>> >>> Slashdot TV. >>> >>> Video for Nerds. Stuff that matters. >>> >>> http://tv.slashdot.org/ >>> >>> _______________________________________________ >>> >>> Emc-users mailing list >>> >>> [email protected] >>> >>> https://lists.sourceforge.net/lists/listinfo/emc-users >>> >>> >>> >> >>> >> >>> >> >>> >> >>> ------------------------------------------------------------------------------ >>> >> Slashdot TV. >>> >> Video for Nerds. Stuff that matters. >>> >> http://tv.slashdot.org/ >>> >> _______________________________________________ >>> >> Emc-users mailing list >>> >> [email protected] >>> >> https://lists.sourceforge.net/lists/listinfo/emc-users >>> >> >>> >> >>> > >>> ------------------------------------------------------------------------------ >>> > Slashdot TV. >>> > Video for Nerds. Stuff that matters. >>> > http://tv.slashdot.org/ >>> > _______________________________________________ >>> > Emc-users mailing list >>> > [email protected] >>> > https://lists.sourceforge.net/lists/listinfo/emc-users >>> > >>> >>> >>> ------------------------------------------------------------------------------ >>> Slashdot TV. >>> Video for Nerds. Stuff that matters. >>> http://tv.slashdot.org/ >>> _______________________________________________ >>> Emc-users mailing list >>> [email protected] >>> https://lists.sourceforge.net/lists/listinfo/emc-users >>> >>> >> > ------------------------------------------------------------------------------ Slashdot TV. Video for Nerds. Stuff that matters. http://tv.slashdot.org/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
