Re: [Emc-users] : Which mini ITX board to choose? (Rudy du Preez)
The Intel D2800MT actually has a parallel port. It sits on the board and needs a ribbon cable extension. I am currently running a Linuxcnc 2.5.2 on this board with two parports: one in the PCI-E slot and one on the ribbon cable. One is configured as out and the other as in. Rudy -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On Tue, 09 Apr 2013 17:11:00 -0400, you wrote: On Tue, Apr 9, 2013, at 05:04 PM, Steve Blackmore wrote: On Tue, 09 Apr 2013 19:18:13 +0200, you wrote: I tried your value, and it seem you are really close to the max frequency drive for the stepper. Claude - if that were so it would not work with identical settings under Mach3. Same step frequency, same drivers same PC same everything. It might be close to the limits of the EMC step pulse generator (which aren't neccessarily the same as those of the Mach step pulse generator). Personally I think that is unlikely, but the test is relatively straightforward. You could reduce by just a factor of two instead of ten, the key is to drop it by a significant factor on both systems and see if the difference is still there. If the misbehavior is still there, that pretty much rules out step generator limits. Hi John - if I reduce the feed by 50% and the acceleration by 50% it still does it. The router maximum reliable rate is 5200mm/min and is devalued to 4000 for a margin of safety. PC only has a worse latency of around 6500. The router can and does manage the 3600 mm/min feed easily in both mach and LinuxCNC, but slows horribly on line to arc or arc to line transitions in LinuxCNC. Arc to arc is ok, as is line to line? Steve Blackmore -- -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On Tue, 9 Apr 2013 23:44:23 +0100, you wrote: On 9 April 2013 23:14, Steve Blackmore st...@pilotltd.net wrote: The problem is apparent at the first G2 move. The machine appears to change feedrate between G2 and G1 moves. Moving from one G2 line to another G2 line is smooth, and moving from one G1 line to another G1 line is smooth. G1 moves appear to run at around 60% of the feedrate of the G2 moves, That does seem to be what you are seeing. However I just tried a test 200mm move and a 32.8mm radius circle and they both took the same length of time Do you get the same result? (I was running in a sim, so it might not be a valid test) Do a line connected to an arc and vice versa then try. The slowdown is on the transition here. If you run the code you can actually see the slowdown on the feed display in the gui in Axis. Steve Blackmore -- -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On 10 April 2013 08:24, Steve Blackmore st...@pilotltd.net wrote: Do a line connected to an arc and vice versa then try. The slowdown is on the transition here. If you run the code you can actually see the slowdown on the feed display in the gui in Axis. I put that down to the arcs and lines not being tangents, so there is a sharp corner at each transition (I have checked in a CAD package, the lines and arcs are _not_ tangents.) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
Agree, for example this line to arc is NOT tangent: N300 G1 X4.121 Y88.649 Z-1.000 N310 G1 X4.891 Y91.654 Z-1.000 N320 G2 X8.045 Y101.818 I125.643 J-33.412 I don't know what mach3 is doing to go full speed trough this, but it is theoretically not possible to go full continuous speed trough this without having infinite acceleration (assuming perfect position of course!). Claude Le 10.04.2013 11:22, andy pugh a écrit : On 10 April 2013 08:24, Steve Blackmore st...@pilotltd.net wrote: Do a line connected to an arc and vice versa then try. The slowdown is on the transition here. If you run the code you can actually see the slowdown on the feed display in the gui in Axis. I put that down to the arcs and lines not being tangents, so there is a sharp corner at each transition (I have checked in a CAD package, the lines and arcs are _not_ tangents.) -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
Cutting corners for sure... On 4/10/2013 6:10 AM, Claude Froidevaux wrote: Agree, for example this line to arc is NOT tangent: N300 G1 X4.121 Y88.649 Z-1.000 N310 G1 X4.891 Y91.654 Z-1.000 N320 G2 X8.045 Y101.818 I125.643 J-33.412 I don't know what mach3 is doing to go full speed trough this, but it is theoretically not possible to go full continuous speed trough this without having infinite acceleration (assuming perfect position of course!). Claude Le 10.04.2013 11:22, andy pugh a écrit : On 10 April 2013 08:24, Steve Blackmore st...@pilotltd.net wrote: Do a line connected to an arc and vice versa then try. The slowdown is on the transition here. If you run the code you can actually see the slowdown on the feed display in the gui in Axis. I put that down to the arcs and lines not being tangents, so there is a sharp corner at each transition (I have checked in a CAD package, the lines and arcs are _not_ tangents.) -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
What do you think about this guys, and their approach to high speed machining: http://youtu.be/w7B8C9Rv-eo?t=23s Their machines are sure capable of really high accelerations, but there is probably done something also on controllers side (approximations of path)? -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Closed loop stepping system
This system http://www.automationtechnologiesinc .com/products-page/nema23-closed-loop-stepper-motor-system-hybrid-servo-kit/hybrid-servo-drive-kl-5080h Is apparently a stepper motor that is controlled as a brushless. Essentially a stepper is a brushless. This needs a encoder, probably one with a index pulse correctly positioned, so that the electronics can compute the switching accurately. This means, even if the control of the drive looks like a STEP DIR control, internally there are position and current loops, theoretically such a drive could offer, velocity and current control (I've not checked for the above reference). This means essentially that, the motor runs cooler, because only the required intensity is flowing in the motor, and not the maximum required intensity (the one that is controlled with the typical potentiometer in typical stepper drives). This means as well that the motor runs smoother, this must be most noticeable at low velocities, and finally that the positioning can be as precise as the encoder is. I regard of precision, note that a stepper, is not as precise as 3600/steps_per_revolution/microsteps, because microsteps don need to be equally spaced, even steps are not precise due to manufacturing (magnetic field) do not have to be equally spaced. In addition to this forces make that the motor is not centered at the center of the microstep. In comparison a brushless type encoder based drive for steeper can be as precise as the encoder, you know the actual position with the encoder position, although the position can be different of the commanded position, but you know the difference. The only limitations seem to be related to control at hih rpms, performance degrades in comparison with brushless. I would say that this is related to the higher pole count of the steeper,and the inherent dificulty to stablish intensity at high pole conmutation frecuency due to impedance, something that con be alleviated increaing voltage as much as possible.. In regard to this the error position, it can be even smaller in this brushless system because, as it runs cooler, you can allow for small duration current higher than the nominal. For a steeper you can not surpass the nominal value, not for the motor not for the electronics. I've never run a system of this type, but I would love to use one of the MESA cards and brushless firmwares to test a such a setup (I'm interested in current control) if somebody with more experience thinks/knowns this is possible and not too difficult. Just using a double shaft stepper and a cheap encoder. I would love, to identify stepper cogging, and to software compensate for it. This said, if the proposed system works as theoretically expected, it looks to me it has a pretty reasonable price. Regard, Javier On Wed, Apr 10, 2013 at 6:45 AM, Viesturs Lācis viesturs.la...@gmail.comwrote: 2013/4/10 Tomaz T. tomaz_...@hotmail.com The whole point is that I don't have any feedback from steppers at this stage, and as I said, the cheapest solution would be to simply change the existing one with the one with closed loop future (and also drivers). So the basic idea might be to use In-Position signal (output) from stepper driver and when this goes fault, it triggers following error in linuxcnc. Could this work? So why don't You put encoders on stepper motors and link encoder position to axis.n.motor-pos-fb pin and let LinuxCNC track actual motor position and it definitely will trigger following error, once it has been reached. This way there are no fancy stepper drives and motors are required. Anyone using this stepper system from kelinginc? http://www.automationtechnologiesinc.com/products-page/nema23-closed-loop-stepper-motor-system-hybrid-servo-kit/hybrid-servo-drive-kl-5080h No tuning of feedback loop? Well, then I do not see, how does this system achieve its goal and correct for motor's position error. -- Viesturs If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account!
Re: [Emc-users] Will LinuxCNC work with a CandCNC Dragon Cut system?
On 10 April 2013 05:22, Gregg Eshelman g_ala...@yahoo.com wrote: Looking further down the road, it looks as if a switch to LinuxCNC will be required if/when 2-axis torch tilt gets added to the plasma table it uses both the parallel port and the serial port. It would be useful to know how the serial port is being used. it also uses parallel-port multiplexing (which is partly clever, and partly mad). So, I think it would need some effort to make it work with LinuxCNC. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Which mini ITX board to choose?
Dear Peter, will a 5i20 work in the ga-e350n with pci slot? i have one 5i20 at hand and looking to buy some 350n. Regards rick 2013/4/9 Peter C. Wallace p...@mesanet.com On Tue, 9 Apr 2013, Eric Keller wrote: Date: Tue, 9 Apr 2013 10:28:11 -0400 From: Eric Keller eekel...@psu.edu Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: Re: [Emc-users] Which mini ITX board to choose? On Tue, Apr 9, 2013 at 9:13 AM, andy pugh bodge...@gmail.com wrote: The 6i25 ought to work. That looks to be a 16x slot, running x4, that can negotiate down to x1 with a 6i25 in there. (But check with Mesa) that's weird, when I go to newegg they have a ga-e350N with a PCI slot that's in stock and one with a PCIe slot that isn't. There are 2 GA-E350Ns: the plain GA-350N that has a PCI slot, and the GA-E350N-USB3 that has a 4 lane PCIE slot (16 physical) Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Closed loop stepping system
On 10 April 2013 12:18, Javier Ros j...@unavarra.es wrote: Is apparently a stepper motor that is controlled as a brushless. Essentially a stepper is a brushless. This needs a encoder, probably one with a index pulse correctly positioned, so that the electronics can compute the switching accurately. The Mesa 7i32 does this too. Note that this is _not_ a Hostmot2 device, it needs to be controlled by SoftDMC and there is (As far as I know) no official LinuxCNC support, though there is a component http://wiki.linuxcnc.org/cgi-bin/wiki.pl?ContributedComponents#Mesa_7i32_micro_stepping_motor_driver -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Which mini ITX board to choose?
Also, the ga-e350n-usb3 (4x pci-e slot), is compatible with an 6i25?. I will test first the ga-e350n. regards rick 2013/4/10 Ricardo Moscoloni rmoscol...@gmail.com Dear Peter, will a 5i20 work in the ga-e350n with pci slot? i have one 5i20 at hand and looking to buy some 350n. Regards rick 2013/4/9 Peter C. Wallace p...@mesanet.com On Tue, 9 Apr 2013, Eric Keller wrote: Date: Tue, 9 Apr 2013 10:28:11 -0400 From: Eric Keller eekel...@psu.edu Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: Re: [Emc-users] Which mini ITX board to choose? On Tue, Apr 9, 2013 at 9:13 AM, andy pugh bodge...@gmail.com wrote: The 6i25 ought to work. That looks to be a 16x slot, running x4, that can negotiate down to x1 with a 6i25 in there. (But check with Mesa) that's weird, when I go to newegg they have a ga-e350N with a PCI slot that's in stock and one with a PCIe slot that isn't. There are 2 GA-E350Ns: the plain GA-350N that has a PCI slot, and the GA-E350N-USB3 that has a 4 lane PCIE slot (16 physical) Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Inductive Coupling
I have bought a Renishaw touch-probe. It has an inductive interface to connect to the controller, described in patent GB2025073 It appears that an LC circuit in the probe is shorted out by the probe contacts when there is no contact. All fairly simple, though finding what the resonant frequency is is probably important. I am trying to think what might be a suitable device for the receiver. I guess I could wind a couple of sets of windings round a ferrite, but there is probably something off-the-shelf that will work. I am even pondering the idea of sensing it with a spare Resolver output from my Mesa 7i49 card. I suspect that if I had three windings on the ferrite, with one further away from the probe than the other then I would see a shift in apparent resolver angle, and could use that as my probe input. Maybe air-core would work better? -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Which mini ITX board to choose?
There seem to be 4 models of E350N board. The GA-E350N (rev 1.0) the GA-350N (rev 3.0) and the GA-E350N Win8 (rev 1.0) all seem to have a parallel port, but the GA-E350N-USB3 (rev 1.0) does not. The -USB3 has a different chipset (AMD 50M as opposed to AMD A45 FCH) but I don't know enough about those to be able to comment on the effects they might have on latency. I assume the latency test was carried out on the plain E350N, and it looks like a good solution at a reasonable price. A review on hardware.info says: Gigabyte submitted two E-350 motherboards, the GA-E350N (£60) and the GA-E350N-USB3. The first one almost almost seems intended for industrial applications, due to the presence of CPI instead of PCI-Express x16 and the inclusion of old-fashioned parallel printer and serial ports. For consumers these are useless. The board use the cheap A45 chipset which gives it 4x SATA300 (and not SATA600). The Realtek ALC887 audio codec is also old. The power consumption is very high for this board. The reviewers liked the -USB3 a lot better, but then its newer, so I guess they would, wouldn't they? I think the issue here is that the parallel port will disappear quickly, so we need good solutions ready for that time. Trouble is, those solutions cost extra, and while they might add value (speed, consistency, or whatever), the effect of the cheaper motherboards boards is largely negated. Marcus On 10 Apr 2013, at 13:39, Ricardo Moscoloni wrote: Also, the ga-e350n-usb3 (4x pci-e slot), is compatible with an 6i25?. I will test first the ga-e350n. regards rick 2013/4/10 Ricardo Moscoloni rmoscol...@gmail.com Dear Peter, will a 5i20 work in the ga-e350n with pci slot? i have one 5i20 at hand and looking to buy some 350n. Regards rick 2013/4/9 Peter C. Wallace p...@mesanet.com On Tue, 9 Apr 2013, Eric Keller wrote: Date: Tue, 9 Apr 2013 10:28:11 -0400 From: Eric Keller eekel...@psu.edu Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: Re: [Emc-users] Which mini ITX board to choose? On Tue, Apr 9, 2013 at 9:13 AM, andy pugh bodge...@gmail.com wrote: The 6i25 ought to work. That looks to be a 16x slot, running x4, that can negotiate down to x1 with a 6i25 in there. (But check with Mesa) that's weird, when I go to newegg they have a ga-e350N with a PCI slot that's in stock and one with a PCIe slot that isn't. There are 2 GA-E350Ns: the plain GA-350N that has a PCI slot, and the GA-E350N-USB3 that has a 4 lane PCIE slot (16 physical) Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Inductive Coupling
It might be operating at a low frequency, but you could try tuning for it on a handheld radio, like a small transistor MW radio held up close. Even way off-frequency you might be able to detect the difference between ON and OFF. You could then hunt for the strongest signal. Marcus On 10 Apr 2013, at 13:56, andy pugh wrote: I have bought a Renishaw touch-probe. It has an inductive interface to connect to the controller, described in patent GB2025073 It appears that an LC circuit in the probe is shorted out by the probe contacts when there is no contact. All fairly simple, though finding what the resonant frequency is is probably important. I am trying to think what might be a suitable device for the receiver. I guess I could wind a couple of sets of windings round a ferrite, but there is probably something off-the-shelf that will work. I am even pondering the idea of sensing it with a spare Resolver output from my Mesa 7i49 card. I suspect that if I had three windings on the ferrite, with one further away from the probe than the other then I would see a shift in apparent resolver angle, and could use that as my probe input. Maybe air-core would work better? -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Inductive Coupling
On 4/10/2013 8:56 AM, andy pugh wrote: I have bought a Renishaw touch-probe. I infer you bought only the probe and not the receiver. It has an inductive interface to connect to the controller, described in patent GB2025073 It appears that an LC circuit in the probe is shorted out by the probe contacts when there is no contact. All fairly simple, though finding what the resonant frequency is is probably important. It's been 50 years since I last used a grid-dip meter but it's one way to get the job done if you want to know the resonant frequency of a tuned circuit. Regards, Kent -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Inductive Coupling
On 10 April 2013 14:42, Kent A. Reed kentallanr...@gmail.com wrote: On 4/10/2013 8:56 AM, andy pugh wrote: I have bought a Renishaw touch-probe. I infer you bought only the probe and not the receiver. The consensus on IRC was that bought might be a misnomer, and stole was closer. http://www.ebay.co.uk/itm/Renshaw-Mp3-Probe-/271177751112 -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
I'd like to weigh in with the following test: Running LCNC 2.5, copy the sim/axis config to your local configs, then change the max_acceleration for axis 0, 1, and 2 to 1.0 (previously 100): MAX_ACCELERATION = 1.0 Then run both of the following programs: % (1 inch square) G90 G54 G20 G64 P.125 G0 X0 Y0 Z0 G1 Y1 F50 X1 Y0 X0 m30 % (1 square with rounded corners) G90 G54 G20 G64 G0 X0 Y.25 Z0 G1 Y.75 F50 G2 X.25 Y1 I.25 G1 X.75 G2 X1 Y.75 J-.25 G1 Y.25 G2 X.75 Y0 I-.25 G1 X.25 G2 X0 Y.25 J.25 M30 The tool path on both programs is nearly identical because the square with hard corners is run at G64 P.125. http://static.inky.ws/image/3839/Screenshot-rounded_square.ngc%20-%20AXIS%202.5.0%20on%20LinuxCNC-HAL-SIM-AXIS.png If you watch the velocity display you will see that the program with only line-line transitions (1 square) reaches 35 inches/min - while the program with line-arc or arc-line transitions (1 rounded square) runs at only 26 inches/min. The arcs are certainly tangent here, and no one can point blame at the CAM software (although you're welcome to point blame at my poor hand coding style). Daniel Rogge Axis.ini file contents are: # EMC controller parameters for a simulated machine. # General note: Comments can either be preceded with a # or ; - either is # acceptable, although # is in keeping with most linux config files. # General section - [EMC] # Version of this INI file VERSION = $Revision$ # Name of machine, for use with display, etc. MACHINE = LinuxCNC-HAL-SIM-AXIS # Debug level, 0 means no messages. See src/emc/nml_int/emcglb.h for others #DEBUG = 0x7FFF DEBUG = 0 # Sections for display options [DISPLAY] # Name of display program, e.g., xemc DISPLAY = axis # Cycle time, in seconds, that display will sleep between polls CYCLE_TIME =0.100 # Path to help file HELP_FILE = doc/help.txt # Initial display setting for position, RELATIVE or MACHINE POSITION_OFFSET = RELATIVE # Initial display setting for position, COMMANDED or ACTUAL POSITION_FEEDBACK = ACTUAL # Highest value that will be allowed for feed override, 1.0 = 100% MAX_FEED_OVERRIDE = 1.2 MAX_SPINDLE_OVERRIDE = 1.0 MAX_LINEAR_VELOCITY = 1.2 DEFAULT_LINEAR_VELOCITY = .25 # Prefix to be used PROGRAM_PREFIX = /home/rogge/linuxcnc/nc_files # Introductory graphic INTRO_GRAPHIC = linuxcnc.gif INTRO_TIME = 5 EDITOR = gedit TOOL_EDITOR = tooledit INCREMENTS = 1 in, 0.1 in, 10 mil, 1 mil, 1mm, .1mm, 1/8000 in [FILTER] PROGRAM_EXTENSION = .png,.gif,.jpg Grayscale Depth Image PROGRAM_EXTENSION = .py Python Script png = image-to-gcode gif = image-to-gcode jpg = image-to-gcode py = python # Task controller section - [TASK] # Name of task controller program, e.g., milltask TASK = milltask # Cycle time, in seconds, that task controller will sleep between polls CYCLE_TIME =0.001 # Part program interpreter section [RS274NGC] # File containing interpreter variables PARAMETER_FILE = sim.var # Motion control section -- [EMCMOT] EMCMOT = motmod # Timeout for comm to emcmot, in seconds COMM_TIMEOUT = 1.0 # Interval between tries to emcmot, in seconds COMM_WAIT = 0.010 # BASE_PERIOD is unused in this configuration but specified in core_sim.hal BASE_PERIOD = 0 # Servo task period, in nano-seconds SERVO_PERIOD = 100 # Hardware Abstraction Layer section -- [HAL] # The run script first uses halcmd to execute any HALFILE # files, and then to execute any individual HALCMD commands. # # list of hal config files to run through halcmd # files are executed in the order in which they appear HALFILE = core_sim.hal HALFILE = axis_manualtoolchange.hal HALFILE = simulated_home.hal # list of halcmd commands to execute # commands are executed in the order in which they appear #HALCMD =save neta # Single file that is executed after the GUI has started. Only supported by # AXIS at this time (only AXIS creates a HAL component of its own) #POSTGUI_HALFILE = test_postgui.hal HALUI = halui # Trajectory planner section -- [TRAJ] AXES = 3 COORDINATES = X Y Z HOME = 0 0 0 LINEAR_UNITS = inch ANGULAR_UNITS = degree CYCLE_TIME =0.010 DEFAULT_VELOCITY = 1.2 POSITION_FILE = position.txt MAX_LINEAR_VELOCITY = 1.2 # Axes sections --- # First axis [AXIS_0] TYPE = LINEAR HOME = 0.000
Re: [Emc-users] Found loading problem?
gene , I love your signature blocks they are one of the highlights of reading your messages :) On Tue, Apr 9, 2013 at 10:55 PM, Gene Heskett ghesk...@wdtv.com wrote: On Tuesday 09 April 2013 22:46:18 Kent A. Reed did opine: On 4/9/2013 12:12 PM, Gene Heskett wrote: Anyway, it looks like it will run on the 2.6.0-pre just fine now. Gene: Glad to hear it works now. At this point I think I'll climb back into my hole before i start hazarding guesses that may serve only to muddy the waters. :-) As for your mix-mastered file, I got lost in your description of the sequence of events. I haven't had a text file corrupted in such a manner since the early days of word processors. Regards, Kent That was a first for me too, in likely 20 or more years. Anyway, the part is now cut out, sharp edges broken, drilled and countersunk for a couple cap screws, and ATM is superglued to the part it will be bolted to once I drill tap the 2 holes for the bolts. Then I'm ready to shorten up the striker spring, put it together see if it will still do a 1.5 group at 50 yards. BP rifle makings IOW. A solidly locked bolt to contain the back thrust of the #209 primer, and a fully legit firing pin, which it never had before. If it works right, the folks on the next bench over won't be accusing me of shooting old butt-burner ever again. Thanks Kent. Cheers, Gene -- There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) My web page: http://coyoteden.dyndns-free.com:85/gene is up! My views http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml The voters have spoken, the bastards... -- unknown A pen in the hand of this president is far more dangerous than a gun in the hands of 200 million law-abiding citizens. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- jeremy youngs -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Inductive Coupling
I have one of those. I bought it for a similar price a few years back. I did look into making an inductive pickup for it but never got very far as I also picked up a Renishaw LP2 probe at about the same time. I made a QC30 holder for the LP2 with an infra red emitter that fires up the hollow spindle on my BP Series 1 CNC (the tools are held by the flange rather than using a drawbar). A simple receiver on the top of the spindle completes the setup. The transmitter has a 1/2AA sized lithium battery that lasts about a year. Hopefully in the next couple of months I'll be getting a Hurco Hawk which doesn't have a hollow spindle so I may look into using the MP3 probe instead. Les On 10/04/2013 15:00, andy pugh wrote: On 10 April 2013 14:42, Kent A. Reed kentallanr...@gmail.com wrote: On 4/10/2013 8:56 AM, andy pugh wrote: I have bought a Renishaw touch-probe. I infer you bought only the probe and not the receiver. The consensus on IRC was that bought might be a misnomer, and stole was closer. http://www.ebay.co.uk/itm/Renshaw-Mp3-Probe-/271177751112 -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Which mini ITX board to choose?
On Wed, 10 Apr 2013, Ricardo Moscoloni wrote: Date: Wed, 10 Apr 2013 09:20:41 -0300 From: Ricardo Moscoloni rmoscol...@gmail.com Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: Re: [Emc-users] Which mini ITX board to choose? Dear Peter, will a 5i20 work in the ga-e350n with pci slot? i have one 5i20 at hand and looking to buy some 350n. Regards rick It should. I dont have a GA-350N (but I have MBs with the same chipset) so I cannot say for sure but I would say its better than 99% likely to work. 2013/4/9 Peter C. Wallace p...@mesanet.com On Tue, 9 Apr 2013, Eric Keller wrote: Date: Tue, 9 Apr 2013 10:28:11 -0400 From: Eric Keller eekel...@psu.edu Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: Re: [Emc-users] Which mini ITX board to choose? On Tue, Apr 9, 2013 at 9:13 AM, andy pugh bodge...@gmail.com wrote: The 6i25 ought to work. That looks to be a 16x slot, running x4, that can negotiate down to x1 with a 6i25 in there. (But check with Mesa) that's weird, when I go to newegg they have a ga-e350N with a PCI slot that's in stock and one with a PCIe slot that isn't. There are 2 GA-E350Ns: the plain GA-350N that has a PCI slot, and the GA-E350N-USB3 that has a 4 lane PCIE slot (16 physical) Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Which mini ITX board to choose?
On Wed, 10 Apr 2013, Ricardo Moscoloni wrote: Date: Wed, 10 Apr 2013 09:39:52 -0300 From: Ricardo Moscoloni rmoscol...@gmail.com Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: Re: [Emc-users] Which mini ITX board to choose? Also, the ga-e350n-usb3 (4x pci-e slot), is compatible with an 6i25?. I will test first the ga-e350n. regards rick _maybe_. Despite the PCIE specs saying that cards must be downward compatible (card lanes slot lanes should work), Many BIOSes flub this. Its likely that it works but I would only know if it was tested. 2013/4/10 Ricardo Moscoloni rmoscol...@gmail.com Dear Peter, will a 5i20 work in the ga-e350n with pci slot? i have one 5i20 at hand and looking to buy some 350n. Regards rick 2013/4/9 Peter C. Wallace p...@mesanet.com On Tue, 9 Apr 2013, Eric Keller wrote: Date: Tue, 9 Apr 2013 10:28:11 -0400 From: Eric Keller eekel...@psu.edu Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: Re: [Emc-users] Which mini ITX board to choose? On Tue, Apr 9, 2013 at 9:13 AM, andy pugh bodge...@gmail.com wrote: The 6i25 ought to work. That looks to be a 16x slot, running x4, that can negotiate down to x1 with a 6i25 in there. (But check with Mesa) that's weird, when I go to newegg they have a ga-e350N with a PCI slot that's in stock and one with a PCIe slot that isn't. There are 2 GA-E350Ns: the plain GA-350N that has a PCI slot, and the GA-E350N-USB3 that has a 4 lane PCIE slot (16 physical) Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Inductive Coupling
On 10 April 2013 15:18, Les Newell les.new...@fastmail.co.uk wrote: Hopefully in the next couple of months I'll be getting a Hurco Hawk which doesn't have a hollow spindle so I may look into using the MP3 probe instead. I was planning on using a hardwired connection, as the IMP module does lose me some precious Z-height, but the tinkerer in me wants to work out the clever system. I was planning to make a magsafe style connector for the probe that will break free in case of inadvertant spindle start. I am undecided on what I will end up with. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Inductive Coupling
On Wed, 10 Apr 2013, andy pugh wrote: Date: Wed, 10 Apr 2013 13:56:17 +0100 From: andy pugh bodge...@gmail.com Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: [Emc-users] Inductive Coupling I have bought a Renishaw touch-probe. It has an inductive interface to connect to the controller, described in patent GB2025073 It appears that an LC circuit in the probe is shorted out by the probe contacts when there is no contact. All fairly simple, though finding what the resonant frequency is is probably important. I am trying to think what might be a suitable device for the receiver. I guess I could wind a couple of sets of windings round a ferrite, but there is probably something off-the-shelf that will work. I am even pondering the idea of sensing it with a spare Resolver output from my Mesa 7i49 card. I suspect that if I had three windings on the ferrite, with one further away from the probe than the other then I would see a shift in apparent resolver angle, and could use that as my probe input. Maybe air-core would work better? I suspect just making a driver that senses the load or phase of the drive coil would be the simplest. Whether Air or ferrite is better depends mostly on the carrier frequency (does the patent give a hint?) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Inductive Coupling
On Wed, 10 Apr 2013, andy pugh wrote: Date: Wed, 10 Apr 2013 15:58:25 +0100 From: andy pugh bodge...@gmail.com Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: Re: [Emc-users] Inductive Coupling On 10 April 2013 15:18, Les Newell les.new...@fastmail.co.uk wrote: Hopefully in the next couple of months I'll be getting a Hurco Hawk which doesn't have a hollow spindle so I may look into using the MP3 probe instead. I was planning on using a hardwired connection, as the IMP module does lose me some precious Z-height, but the tinkerer in me wants to work out the clever system. I was planning to make a magsafe style connector for the probe that will break free in case of inadvertant spindle start. I am undecided on what I will end up with. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto The patent has a schematic of the receiver which is very simple. basically its just a self resonant oscillator thats coupled to the LC resonant circuit in the probe. They are using one shots to sense the frequency shift (probably large, maybe 2-1 or more depending on how close the inductors are coupled) Toughest part is probably finding the right shaped ferrite to couple well with the ferrite in the probe. Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Inductive Coupling
I looked at our renishaw knock off for about 15 minutes then decided to pull the Glue mystery out and use the contacts.. http://electronicsam.com/images/KandT/probe/DSCF1507%5B1%5D.jpg http://electronicsam.com/images/KandT/probe/DSCF1508.jpg I do have to plug it in - but I got working a lot quicker than I would have otherwise... (btw - I don't know how I lived without one...) https://www.youtube.com/watch?v=U61ub6mtpH4 sam On 4/10/2013 7:56 AM, andy pugh wrote: I have bought a Renishaw touch-probe. It has an inductive interface to connect to the controller, described in patent GB2025073 It appears that an LC circuit in the probe is shorted out by the probe contacts when there is no contact. All fairly simple, though finding what the resonant frequency is is probably important. I am trying to think what might be a suitable device for the receiver. I guess I could wind a couple of sets of windings round a ferrite, but there is probably something off-the-shelf that will work. I am even pondering the idea of sensing it with a spare Resolver output from my Mesa 7i49 card. I suspect that if I had three windings on the ferrite, with one further away from the probe than the other then I would see a shift in apparent resolver angle, and could use that as my probe input. Maybe air-core would work better? -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] : Which mini ITX board to choose? (Rudy du Preez)
On Wednesday 10 April 2013 11:40:26 Rudy du Preez did opine: The Intel D2800MT actually has a parallel port. It sits on the board and needs a ribbon cable extension. Can the ribbon cable be fed directly to a B.O.B. such as Leonardo's CNC4PC model C1G?, bypassing at least one set of db25's? Sounds cool if you can get the cable out of a box like the 350 mini itx box. I am currently running a Linuxcnc 2.5.2 on this board with two parports: one in the PCI-E slot and one on the ribbon cable. One is configured as out and the other as in. Rudy -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene -- There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) My web page: http://coyoteden.dyndns-free.com:85/gene is up! My views http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml Many are called, few are chosen. Fewer still get to do the choosing. A pen in the hand of this president is far more dangerous than a gun in the hands of 200 million law-abiding citizens. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] : Which mini ITX board to choose? (Rudy du Preez)
On 10 April 2013 16:43, Gene Heskett ghesk...@wdtv.com wrote: Can the ribbon cable be fed directly to a B.O.B. such as Leonardo's CNC4PC model C1G?, bypassing at least one set of db25's? Yes. Even better, it can go direct to the identical header on a Mesa 7i43. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On Wednesday 10 April 2013 11:43:50 Steve Blackmore did opine: On Tue, 09 Apr 2013 17:11:00 -0400, you wrote: On Tue, Apr 9, 2013, at 05:04 PM, Steve Blackmore wrote: On Tue, 09 Apr 2013 19:18:13 +0200, you wrote: I tried your value, and it seem you are really close to the max frequency drive for the stepper. Claude - if that were so it would not work with identical settings under Mach3. Same step frequency, same drivers same PC same everything. It might be close to the limits of the EMC step pulse generator (which aren't neccessarily the same as those of the Mach step pulse generator). Personally I think that is unlikely, but the test is relatively straightforward. You could reduce by just a factor of two instead of ten, the key is to drop it by a significant factor on both systems and see if the difference is still there. If the misbehavior is still there, that pretty much rules out step generator limits. Hi John - if I reduce the feed by 50% and the acceleration by 50% it still does it. The router maximum reliable rate is 5200mm/min and is devalued to 4000 for a margin of safety. PC only has a worse latency of around 6500. The router can and does manage the 3600 mm/min feed easily in both mach and LinuxCNC, but slows horribly on line to arc or arc to line transitions in LinuxCNC. Arc to arc is ok, as is line to line? Steve Blackmore FWIW, I noted that despite a g64.1 P.001 at the top of the file, my carving of that brass handle yesterday on a 2.6.0-pre install, was also coming to a complete stop at those straight line to arc transitions, 4 times per loop, not all of which have a bunch of math between them. So I'd guess on that job, it wasted a minute of the 41 it took to run the final version. I wasn't going that fast anyway, trying to hold down bit flex in 3/4 of a .125 2 flute end mill, F=5 ipm IIRC with smallish cuts in the .007 x .011 thou range, made nice sandy brass swarf, but the stops sure were obvious. Its doing little if any blending, but the stops also did not leave an obviously noticeable mark so the finish was not adversely effected. Cheers, Gene -- There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) My web page: http://coyoteden.dyndns-free.com:85/gene is up! My views http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml Many are called, few are chosen. Fewer still get to do the choosing. A pen in the hand of this president is far more dangerous than a gun in the hands of 200 million law-abiding citizens. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] : Which mini ITX board to choose? (Rudy du Preez)
2013/4/10 andy pugh bodge...@gmail.com On 10 April 2013 16:43, Gene Heskett ghesk...@wdtv.com wrote: Can the ribbon cable be fed directly to a B.O.B. such as Leonardo's CNC4PC model C1G?, bypassing at least one set of db25's? Yes. Even better, it can go direct to the identical header on a Mesa 7i43. And keep all that cable inside the control box... That is why I prefer having such a header right on motherboard, just like D510MO board had. I have difficulties figuring out, how to get that cable back inside in a nice and good-looking way. -- Viesturs If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On Wednesday 10 April 2013 11:58:51 andy pugh did opine: On 10 April 2013 08:24, Steve Blackmore st...@pilotltd.net wrote: Do a line connected to an arc and vice versa then try. The slowdown is on the transition here. If you run the code you can actually see the slowdown on the feed display in the gui in Axis. I put that down to the arcs and lines not being tangents, so there is a sharp corner at each transition (I have checked in a CAD package, the lines and arcs are _not_ tangents.) Are you saying that the g2-3 code, set to do a 180 turn, is only doing a 179.9 turn? Example in G91.1 relative mode, starting from x y+nn, g2 y-nn i0.0 j=y_radius, is not doing a fully 180 degree from top (x y+nn) to bottom (x y-nn) motion? Cheers, Gene -- There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) My web page: http://coyoteden.dyndns-free.com:85/gene is up! My views http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml Either I'm dead or my watch has stopped. -- Groucho Marx's last words A pen in the hand of this president is far more dangerous than a gun in the hands of 200 million law-abiding citizens. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Closed loop stepping system
On Wednesday 10 April 2013 13:01:29 Javier Ros did opine: This system http://www.automationtechnologiesinc .com/products-page/nema23-closed-loop-stepper-motor-system-hybrid-servo- kit/hybrid-servo-drive-kl-5080h Is apparently a stepper motor that is controlled as a brushless. Essentially a stepper is a brushless. This needs a encoder, probably one with a index pulse correctly positioned, so that the electronics can compute the switching accurately. This means, even if the control of the drive looks like a STEP DIR control, internally there are position and current loops, theoretically such a drive could offer, velocity and current control (I've not checked for the above reference). This means essentially that, the motor runs cooler, because only the required intensity is flowing in the motor, and not the maximum required intensity (the one that is controlled with the typical potentiometer in typical stepper drives). This means as well that the motor runs smoother, this must be most noticeable at low velocities, and finally that the positioning can be as precise as the encoder is. I regard of precision, note that a stepper, is not as precise as 3600/steps_per_revolution/microsteps, because microsteps don need to be equally spaced, even steps are not precise due to manufacturing (magnetic field) do not have to be equally spaced. In addition to this forces make that the motor is not centered at the center of the microstep. Let me fine tune this by pointing out that the stepper motor maker can, with access to the maps the controller uses to adjust its currents when microstepping, could be fine tuned such that at light loading, the microsteps can be pretty accurate. This of course means the motor and the controller must be calibrated to each other. That will be the makers job since few if any of us have the tools to do that, and it sure wouldn't be feasible economically for everyone to own their own stuff to do that. More just plain old comment: The noise would likely go down a bit, but since we aren't also throttling the current in many drivers (mine does after about a second of no motion, so mine only heat about 15F when idle), the motor is still going to run hot. The ideal situation would be by adjusting the overall currents to keep the motor within say 20%/microstep of the ideal microstepped position, but again this would require a high precision encoder, or some sort of magnetically detected feedback to detect the error in real time only use enough current to achieve that. But at that point, you may as well spend the money on a servo system, which may well be what this outfit is doing. Net cost will be similar. My current stepper setup, using 425oz motors on the lathe, was just under $100/axis. This is only a 252oz motor and costs USD 210/axis. I can't seem to justify the extra sheckel's for me. In comparison a brushless type encoder based drive for steeper can be as precise as the encoder, you know the actual position with the encoder position, although the position can be different of the commanded position, but you know the difference. The only limitations seem to be related to control at hih rpms, performance degrades in comparison with brushless. I would say that this is related to the higher pole count of the steeper,and the inherent dificulty to stablish intensity at high pole conmutation frecuency due to impedance, something that con be alleviated increaing voltage as much as possible.. In regard to this the error position, it can be even smaller in this brushless system because, as it runs cooler, you can allow for small duration current higher than the nominal. For a steeper you can not surpass the nominal value, not for the motor not for the electronics. Theoretically true. The motor can be banged with considerable overcurrent when it is lightly loaded and essentially exactly in position, but if half s step off or more due to heavy loading, then the rotor's magnetism could be effected, permanently damaging the motor. I've never run a system of this type, but I would love to use one of the MESA cards and brushless firmwares to test a such a setup (I'm interested in current control) if somebody with more experience thinks/knowns this is possible and not too difficult. Just using a double shaft stepper and a cheap encoder. I would love, to identify stepper cogging, and to software compensate for it. A moot point IMO when the gearing is such that 1 microstep is a fraction of a micron without resorting to a doubling of cost per axis. I haven't actually checked, as my step accuracy is the same on both axis's of the lathe, the x is a 2.5mm/turn screw, the z is 5, but the z is also geared down 2/1. On my .0001 dial indicator, I can't see the individual steps. This said, if the proposed system works as theoretically expected, it looks to me it has a pretty reasonable price. Debatable, unless you
Re: [Emc-users] Poor CV
On 4/10/2013 10:01 AM, Daniel Rogge wrote: I'd like to weigh in with the following test: Running LCNC 2.5, copy the sim/axis config to your local configs, then change the max_acceleration for axis 0, 1, and 2 to 1.0 (previously 100): MAX_ACCELERATION = 1.0 Then run both of the following programs: % (1 inch square) G90 G54 G20 G64 P.125 G0 X0 Y0 Z0 G1 Y1 F50 X1 Y0 X0 m30 % (1 square with rounded corners) G90 G54 G20 G64 G0 X0 Y.25 Z0 G1 Y.75 F50 G2 X.25 Y1 I.25 G1 X.75 G2 X1 Y.75 J-.25 G1 Y.25 G2 X.75 Y0 I-.25 G1 X.25 G2 X0 Y.25 J.25 M30 The tool path on both programs is nearly identical because the square with hard corners is run at G64 P.125. http://static.inky.ws/image/3839/Screenshot-rounded_square.ngc%20-%20AXIS%202.5.0%20on%20LinuxCNC-HAL-SIM-AXIS.png If you watch the velocity display you will see that the program with only line-line transitions (1 square) reaches 35 inches/min - while the program with line-arc or arc-line transitions (1 rounded square) runs at only 26 inches/min. The arcs are certainly tangent here, and no one can point blame at the CAM software (although you're welcome to point blame at my poor hand coding style). Daniel: I really like that you have bounded the argument by introducing these two simple test files and using them to compare LinuxCNC behavior to LinuxCNC behavior. On a computer close at hand at my desk I happen to have available a virtual host running Ubuntu 10.04LTS and LinuxCNC2.5.2-189...(a relic of some previous testing) so I ran your two test files. I get the same results you do. Just for fun, on this same computer I installed yet another virtual host running Ubuntu 8.04LTS and EMC2 2.3.0 (installing from the old ubuntu-8.04-desktop-emc2-aj13-i386.iso http://dsplabs.upt.ro/%7Ejuve/emc/get.php?file=ubuntu-8.04-desktop-emc2-aj13-i386.iso). *Again* I get the same results for your two test files: 35+ ipm for the square and 26+ ipm for the rounded square. Evidently, this behavior precedes 2.4. All: I am a total ignoramus when it comes to the trajectory planning and motion control aspects of LinuxCNC. From my seat in the peanut gallery, it seems there is a divide between those who believe we have a proper set of algorithms properly implemented that have been tested successfully and those who believe this reported behavior must mean either the implementation is deficient or the algorithms imperfect (or both!). So far, the two groups of discussants seem to have been talking past each other, both in the 2011 exchanges and now. The following questions are simply my noodling and not any attempt to state a personal position: Do Daniel's two files constitute a valid test? That is to say, should one expect substantially the same behavior when each is executed? If the answer is yes, then why isn't it the behavior the same? If the answer is no, then why should it not be the same behavior? Once the dust has settled I hope the subject can be explained more fully in the LinuxCNC documentation. For some time we have advertised constant velocity control as a feature of EMC/LinuxCNC (usually in an About... section) but try searching on constant velocity. Two technically meaningful pages on the Wiki respond to this search term: http://wiki.linuxcnc.org/emcinfo.pl%3FTrapezoidal_Velocity_Profile_Trajectory_Planner and http://wiki.linuxcnc.org/emcinfo.pl%3FSimple_Tp_Notes. Pardon me, but if this is such an important topic why is it buried? The rest of the docs don't waste many words, as my grandmother used to say, about feed or speed. Just my 2cents worth. Regards, Kent -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] : Which mini ITX board to choose? (Rudy du Preez)
Gene, The pins on the MB is just a double header so you should be able to do that. I am looking at doing just that so I made a visit to the supplier and had a look at the MB to see how they do it. You could always make a little slot in the end plate of the PCI card or pop out one of the unused place holders on the back plate. On 2013/04/10 05:43 PM, Gene Heskett wrote: On Wednesday 10 April 2013 11:40:26 Rudy du Preez did opine: The Intel D2800MT actually has a parallel port. It sits on the board and needs a ribbon cable extension. Can the ribbon cable be fed directly to a B.O.B. such as Leonardo's CNC4PC model C1G?, bypassing at least one set of db25's? Sounds cool if you can get the cable out of a box like the 350 mini itx box. I am currently running a Linuxcnc 2.5.2 on this board with two parports: one in the PCI-E slot and one on the ribbon cable. One is configured as out and the other as in. Rudy -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene -- Regards / Groete Marius D. Liebenberg MasterCut cc Cel: +27 82 698 3251 Tel: +27 12 743 6064 Fax: +27 86 551 8029 Skype: marius_d.liebenberg Skype Me^(TM)! skype:marius_d.liebenberg?call Get Skype http://www.skype.com/go/download and call me for free. --- avast! Antivirus: Outbound message clean. Virus Database (VPS): 130410-0, 2013/04/10 Tested on: 2013/04/10 08:32:19 PM avast! - copyright (c) 1988-2013 AVAST Software. http://www.avast.com -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Which mini ITX board to choose?
On 4/10/2013 8:59 AM, Marcus Bowman wrote: There seem to be 4 models of E350N board. The GA-E350N (rev 1.0) the GA-350N (rev 3.0) and the GA-E350N Win8 (rev 1.0) all seem to have a parallel port, but the GA-E350N-USB3 (rev 1.0) does not. The -USB3 has a different chipset (AMD 50M as opposed to AMD A45 FCH) but I don't know enough about those to be able to comment on the effects they might have on latency. I assume the latency test was carried out on the plain E350N, and it looks like a good solution at a reasonable price. That's a good point about the latency test. Do not assume! The Biostar A68I-350 Deluxe I remarked on (note, I mistakenly wrote 1 instead of I before) is more like the GA-E350N-USB3 than the GA-350Ns in its design but it has yet again a different Northbridge Chipset (AMD A68). It has USB3 ports and 6GB SATA capability but it also has an internal printer port (!). Just as the Biostar board disappointed me with its 5ns jitter results, the GA-E3350N-USB3 could disappoint. I like Gigabyte boards, but this one needs to be tested! Regards, Kent -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Simple touch probe
Hello! I am looking for a simple and cheap touch probe so that I can fix it near spindle and find material surface in all 3 directions - X, Y and Z. I think that probing repeatability of 0,01 mm will be sufficient for my needs, which does not seem like very high precision for touch probes. I would appreciate any hints, where should I look for something suitable or maybe there is some source of information that describes, how to make one. The size and beauty of the probe itself does not really matter, keeping the budget as low as possible is higher priority. Thanks in advance! -- Viesturs If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On Wed, Apr 10, 2013 at 2:33 PM, Kent A. Reed kentallanr...@gmail.comwrote: From my seat in the peanut gallery, it seems there is a divide between those who believe we have a proper set of algorithms properly implemented that have been tested successfully and those who believe this reported behavior must mean either the implementation is deficient or the algorithms imperfect (or both!). So far, the two groups of discussants seem to have been talking past each other, both in the 2011 exchanges and now. The only trajectory planning argument I am aware of is the one step lookahead argument. I don't know if this really is an artifact of the one-step lookahead or not. Seems like it might not be. If someone came up with a trajectory planner that worked better than the current one, I suspect it would be made available. So far all I see is people saying that it really should be done and then waiting for someone to do it. Right now, the people that write code prefer robustness over performance, which is a good thing in my view. This does look like a very good test case. If we can figure out why it does this then it should be possible to make inprovements -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Simple touch probe
On 4/10/2013 2:57 PM, Viesturs Lācis wrote: Hello! I am looking for a simple and cheap touch probe so that I can fix it near spindle and find material surface in all 3 directions - X, Y and Z. Hitting Google with diy touch probe turned up a number of candidates. You could start with http://fadedbits.com/2011/02/touchprobe/ and http://gtocs.blogspot.com/2012/04/garys-diy-cnc-touch-probe.html. Just about every DIY'er reports using his/her probe with EMC2 or LinuxCNC. I think that probing repeatability of 0,01 mm will be sufficient for my needs, which does not seem like very high precision for touch probes. That seems doable if the above sites are telling the truth. Regards, Kent -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Simple touch probe
On 10 April 2013 19:57, Viesturs Lācis viesturs.la...@gmail.com wrote: I am looking for a simple and cheap touch probe so that I can fix it near spindle and find material surface in all 3 directions - X, Y and Z. http://www.homanndesigns.com/store/index.php?main_page=product_infoproducts_id=217 Is the cheapest I know of. (unless you get lucky on eBay) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
snip-snap All: I am a total ignoramus when it comes to the trajectory planning and motion control aspects of LinuxCNC. From my seat in the peanut gallery, it seems there is a divide between those who believe we have a proper set of algorithms properly implemented that have been tested successfully and those who believe this reported behavior must mean either the implementation is deficient or the algorithms imperfect (or both!). So far, the two groups of discussants seem to have been talking past each other, both in the 2011 exchanges and now. The following questions are simply my noodling and not any attempt to state a personal position: Do Daniel's two files constitute a valid test? That is to say, should one expect substantially the same behavior when each is executed? If the answer is yes, then why isn't it the behavior the same? If the answer is no, then why should it not be the same behavior? Once the dust has settled I hope the subject can be explained more fully in the LinuxCNC documentation. For some time we have advertised constant velocity control as a feature of EMC/LinuxCNC (usually in an About... section) but try searching on constant velocity. Two technically meaningful pages on the Wiki respond to this search term: http://wiki.linuxcnc.org/emcinfo.pl%3FTrapezoidal_Velocity_Profile_Trajectory_Planner and http://wiki.linuxcnc.org/emcinfo.pl%3FSimple_Tp_Notes. Pardon me, but if this is such an important topic why is it buried? The rest of the docs don't waste many words, as my grandmother used to say, about feed or speed. Just my 2cents worth. Regards, Kent Ah! Back to the future! TP has been endlessly cussed and discussed but it is a non-trivial problem. If it was easy it would have been fixed a long time ago. G64 p was an improvement. So much of this stems from an early in the design process decision that linuxcnc must be able to stop the machine at the end of each block. Les Watts tried something in conjunction with NIST years ago but it never quite worked. I keep hoping someone will have an epiphany that will push tp forward. (npi). Catting short segments into an arc can make a real difference. I suppose if one needs to avoid line to arc transitions then lines could be specified as arcs with a very large radius. No panacea anywhere in sight. Dave -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
--- On Wed, 4/10/13, Tomaz T. tomaz_...@hotmail.com wrote: What do you think about this guys, and their approach to high speed machining: http://youtu.be/w7B8C9Rv-eo?t=23s Their machines are sure capable of really high accelerations, but there is probably done something also on controllers side (approximations of path)? Probably pre-scans the tool path, finds places where arcs and lines are really close to but not quite tangent, says Hey, these are really close! and adjust for it so it can go right through the bump as if it's not there. That's been done by at least one water jet manufacturer, their equipment generates a continuously varied speed/acceleration profile for the path before it starts the cut. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On 10 April 2013 15:01, Daniel Rogge dro...@tormach.com wrote: Running LCNC 2.5, copy the sim/axis config to your local configs, then change the max_acceleration for axis 0, 1, and 2 to 1.0 (previously 100): MAX_ACCELERATION = 1.0 (1 square with rounded corners) G90 G54 G20 G64 G0 X0 Y.25 Z0 G1 Y.75 F50 G2 X.25 Y1 I.25 This is not the same test, as far as I can see. For an arc move the acceleration is v^2 / r, or put another way, the max velocity in an arc is sqrt(a * r) So, in this case, with a 1/4 radius and a 1/s^2 acceleration the max velocity possible is 0.5/s or 30in/min. So, you would expect some slow-down on the corners, but not as much as is being seen. The next limit to consider is that LinuxCNC will always try to stay within its stopping distance due to limited lookahead. The quarter-circles are 0.39in long. To stop at the end of that path segment the entry speed has to be less than 52in/min so the limit isn't there. I think that there are two issues being reported here. The first is that arcs run slower than lines, and I think that might be due to the acceleration limits. The second is a speed glitch passing between line segments and arc segments. This remains unexplained, and I see it in sims too. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On 10 April 2013 21:50, dave dengv...@charter.net wrote: No panacea anywhere in sight. Something I saw somewhere on the Internet (possibly a link from mah) was an article about different approaches. One very interesting idea was that every move as well as being an end-point also includes an end velocity I think that these end velocities need to propagate backwards back up the queue. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On Wed, 10 Apr 2013 06:16:59 -0500, you wrote: Cutting corners for sure... Yes it's deviating by up to by 0.1mm as set in it's config. For LinuxCNC to do a similar feed the deviation has to be 0.5mm? Steve Blackmore -- -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Found loading problem?
On Wednesday 10 April 2013 17:58:47 jeremy youngs did opine: gene , I love your signature blocks they are one of the highlights of reading your messages :) Thanks Jeremy. I don't often let my political views escape my fingertips as body text, but only a few bother reading the sigs. I don't like what they are doing to our constitution and bill of rights over the last 75 years, but they are really getting covered with brown, smelly stains since Reagan left office, and this bunch of popularly elected losers are paying absolutely no attention to it at all. It may be an old pair of documents, but the first never would have passed had the Bill of Rights not accompanied it, giving us assurances of freedom and the tools to control an out of control government. And this one is. But this list is not the list to discuss it on, so other than my sig, no more replies about it please. That last quote I stole from the Cleveland Plains something or other, an editorial of about 2 weeks back. Cheers, Gene -- There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) My web page: http://coyoteden.dyndns-free.com:85/gene is up! My views http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml nominal egg: New Yorkerese for expensive. A pen in the hand of this president is far more dangerous than a gun in the hands of 200 million law-abiding citizens. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On Wed, 10 Apr 2013 22:01:32 +0100, you wrote: On 10 April 2013 21:50, dave dengv...@charter.net wrote: No panacea anywhere in sight. Something I saw somewhere on the Internet (possibly a link from mah) was an article about different approaches. One very interesting idea was that every move as well as being an end-point also includes an end velocity I think that these end velocities need to propagate backwards back up the queue. I think that's what Mach does - or maybe forward in the queue :) Steve Blackmore -- -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] : Which mini ITX board to choose? (Rudy du Preez)
On Wednesday 10 April 2013 18:10:37 andy pugh did opine: On 10 April 2013 16:43, Gene Heskett ghesk...@wdtv.com wrote: Can the ribbon cable be fed directly to a B.O.B. such as Leonardo's CNC4PC model C1G?, bypassing at least one set of db25's? Yes. Even better, it can go direct to the identical header on a Mesa 7i43. Kewl. Cheers, Gene -- There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) My web page: http://coyoteden.dyndns-free.com:85/gene is up! My views http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml Parkinson's Fifth Law: If there is a way to delay in important decision, the good bureaucracy, public or private, will find it. A pen in the hand of this president is far more dangerous than a gun in the hands of 200 million law-abiding citizens. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] : Which mini ITX board to choose? (Rudy du Preez)
On Wednesday 10 April 2013 18:12:55 Marius Liebenberg did opine: Gene, The pins on the MB is just a double header so you should be able to do that. I am looking at doing just that so I made a visit to the supplier and had a look at the MB to see how they do it. You could always make a little slot in the end plate of the PCI card or pop out one of the unused place holders on the back plate. Which is what I did do at one point but with a 50 pin scsi cable from a triple 82C55 based card, and the edges of the hole in the backplane were too sharp for comfort IMO. To be comfy, it would have needed an edge breaker strip installed. And those aren't commodity items here in the middle of WV. :) On 2013/04/10 05:43 PM, Gene Heskett wrote: On Wednesday 10 April 2013 11:40:26 Rudy du Preez did opine: The Intel D2800MT actually has a parallel port. It sits on the board and needs a ribbon cable extension. Can the ribbon cable be fed directly to a B.O.B. such as Leonardo's CNC4PC model C1G?, bypassing at least one set of db25's? Sounds cool if you can get the cable out of a box like the 350 mini itx box. I am currently running a Linuxcnc 2.5.2 on this board with two parports: one in the PCI-E slot and one on the ribbon cable. One is configured as out and the other as in. Rudy Cheers, Gene -- There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) My web page: http://coyoteden.dyndns-free.com:85/gene is up! My views http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml Parkinson's Fifth Law: If there is a way to delay in important decision, the good bureaucracy, public or private, will find it. A pen in the hand of this president is far more dangerous than a gun in the hands of 200 million law-abiding citizens. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On Wed, 10 Apr 2013 13:56:16 -0700 (PDT), you wrote: --- On Wed, 4/10/13, Tomaz T. tomaz_...@hotmail.com wrote: What do you think about this guys, and their approach to high speed machining: http://youtu.be/w7B8C9Rv-eo?t=23s Their machines are sure capable of really high accelerations, but there is probably done something also on controllers side (approximations of path)? Probably pre-scans the tool path, finds places where arcs and lines are really close to but not quite tangent, says Hey, these are really close! and adjust for it so it can go right through the bump as if it's not there. Isn't that what G64 is supposed to do? From the docs G64 - without P means to keep the best speed possible, no matter how far away from the programmed point you end up Clearly it's not doing that. You can see from the video that my router is capable of doing those transitions at only 0.1mm deviation without slowing. Looks like it is not deviating on arc/line transitions in LinuxCNC? Steve Blackmore -- -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
so how far does lcnc actually look ahead? On Wed, Apr 10, 2013 at 6:21 PM, Steve Blackmore st...@pilotltd.net wrote: On Wed, 10 Apr 2013 13:56:16 -0700 (PDT), you wrote: --- On Wed, 4/10/13, Tomaz T. tomaz_...@hotmail.com wrote: What do you think about this guys, and their approach to high speed machining: http://youtu.be/w7B8C9Rv-eo?t=23s Their machines are sure capable of really high accelerations, but there is probably done something also on controllers side (approximations of path)? Probably pre-scans the tool path, finds places where arcs and lines are really close to but not quite tangent, says Hey, these are really close! and adjust for it so it can go right through the bump as if it's not there. Isn't that what G64 is supposed to do? From the docs G64 - without P means to keep the best speed possible, no matter how far away from the programmed point you end up Clearly it's not doing that. You can see from the video that my router is capable of doing those transitions at only 0.1mm deviation without slowing. Looks like it is not deviating on arc/line transitions in LinuxCNC? Steve Blackmore -- -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- jeremy youngs -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On Wed, 10 Apr 2013 11:57:32 -0400, you wrote: FWIW, I noted that despite a g64.1 P.001 at the top of the file, my carving of that brass handle yesterday on a 2.6.0-pre install, was also coming to a complete stop at those straight line to arc transitions, 4 times per loop, not all of which have a bunch of math between them. So I'd guess on that job, it wasted a minute of the 41 it took to run the final version. The time is less relevant to me than a reliable feed rate, but it sure helps to get jobs done as quickly as possible :) Its doing little if any blending, but the stops also did not leave an obviously noticeable mark so the finish was not adversely effected. Yep - none I think. I need to test again, but I'm sure the P and Q values if set high enough make it quicker than G64 on it own which seems contradictory to what the manual says? Unfortunately feed variation can sometimes cause burning on wood. Maple can be a pig for that at times. Quilted or curly is hard to get the feed right, too fast, you tear chunks out, too slow and you burn it. Wood being wood, it's often trial and error on the waste to get it just right and the price I pay for premium timber I can't afford to have misbehaving machines screwing it up. Steve Blackmore -- -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On the water jet site (I want to think it was CMC, but memory is hazy) the comparison between their full path pre scanning and short distance lookahead was that the full pre scan could adjust to things like a long straight followed by a series of curves and short straights by slowing down to a best possible average speed through the twisty section, still managing to speed up a bit where possible. Short distance lookahead is always getting surprised by the next curve, causing rapid attempts to change speed and resulting in lower cut quality and more wear and tear on the machine. Compare it to a skilled race car driver who has made a practice lap and committed every twist and turn to memory, planning out all the gear changes and how fast to go at all points along the course. Short range lookahead is like a semi-skilled driver who has never been on the track before and starts the race without even a practice lap. He can see a turn or two ahead and has the skill to not run off the track, but will try to go as fast as possible all the time and is always having to stomp on the brake at every turn. The skilled driver maintains a smooth speed profile through a chicane while the amateur comes screaming in, hits the brakes hard and has to putt through the curves slowly to avoid spinning off the track. The driver who runs the course before the race ends up lapping the track faster, with less wear on the consumables. So why not have a practice lap simulation that can generate a complete accel/speed/decel profile for a toolpath then feed that data to LinuxCNC? -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
I have also found problems with curve-line and line-curve transitions. My machine is used to paint lines and uses a fourth tangential axis to keep the brush tangent to the tool path. I get significant decelerations/accelerations on these transitions and it shows up as aberrations in the paint stroke. The G code is generated using biarc approximations and all line/curve transitions are tangential (at least to a fairly high degree of precision.) I've tried using different G64 values but it doesn't help much and the tool path precision gets way off. I was going to order a 5i25 card to see if maybe improving the stepgen performance would help, but I'm no CNC expert. Anyway, it's good to know I'm not alone in seeing this behavior. Thanks, - Claude On Wed, Apr 10, 2013 at 4:00 PM, Gregg Eshelman g_ala...@yahoo.com wrote: On the water jet site (I want to think it was CMC, but memory is hazy) the comparison between their full path pre scanning and short distance lookahead was that the full pre scan could adjust to things like a long straight followed by a series of curves and short straights by slowing down to a best possible average speed through the twisty section, still managing to speed up a bit where possible. Short distance lookahead is always getting surprised by the next curve, causing rapid attempts to change speed and resulting in lower cut quality and more wear and tear on the machine. Compare it to a skilled race car driver who has made a practice lap and committed every twist and turn to memory, planning out all the gear changes and how fast to go at all points along the course. Short range lookahead is like a semi-skilled driver who has never been on the track before and starts the race without even a practice lap. He can see a turn or two ahead and has the skill to not run off the track, but will try to go as fast as possible all the time and is always having to stomp on the brake at every turn. The skilled driver maintains a smooth speed profile through a chicane while the amateur comes screaming in, hits the brakes hard and has to putt through the curves slowly to avoid spinning off the track. The driver who runs the course before the race ends up lapping the track faster, with less wear on the consumables. So why not have a practice lap simulation that can generate a complete accel/speed/decel profile for a toolpath then feed that data to LinuxCNC? -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
andy pugh wrote: On 10 April 2013 21:50, dave dengv...@charter.net wrote: No panacea anywhere in sight. Something I saw somewhere on the Internet (possibly a link from mah) was an article about different approaches. One very interesting idea was that every move as well as being an end-point also includes an end velocity I think that these end velocities need to propagate backwards back up the queue. Yes, this was something I proposed about a year ago, I think. Since this propagating backwards is unbounded, it is not something you want to be doing in real time. So, it might have to be done when the file is read in. But, it should solve a number of problems, such as high speed contouring, where there is a pass with bumpy Z moves across a surface, and then a roughly 180 turn to scan back the other way. Jon -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
On Wednesday 10 April 2013 21:56:36 Steve Blackmore did opine: On Wed, 10 Apr 2013 11:57:32 -0400, you wrote: FWIW, I noted that despite a g64.1 P.001 at the top of the file, my carving of that brass handle yesterday on a 2.6.0-pre install, was also coming to a complete stop at those straight line to arc transitions, 4 times per loop, not all of which have a bunch of math between them. So I'd guess on that job, it wasted a minute of the 41 it took to run the final version. The time is less relevant to me than a reliable feed rate, but it sure helps to get jobs done as quickly as possible :) Its doing little if any blending, but the stops also did not leave an obviously noticeable mark so the finish was not adversely effected. Yep - none I think. I need to test again, but I'm sure the P and Q values if set high enough make it quicker than G64 on it own which seems contradictory to what the manual says? Unfortunately feed variation can sometimes cause burning on wood. Maple can be a pig for that at times. Quilted or curly is hard to get the feed right, too fast, you tear chunks out, too slow and you burn it. Wood being wood, it's often trial and error on the waste to get it just right and the price I pay for premium timber I can't afford to have misbehaving machines screwing it up. Steve Blackmore And on my watch, cherry is even worse than maple, as it can rosin up a sharp saw blade and start burning even at a decent feed rate about 10 minutes worth of cutting after you've Easy Off'd the blade with about an half an hours service on it. The best blade I've found I guess I'll have to buy on the net, CMT has one with an ATBF tooth setup, sweetest cutting blade ever. Lowes was carrying it 2 years ago, and I should have stocked up I guess. You can cut an edge with that, and go straight to wiping Sam's Stuff on it, its that smooth. Cheers, Gene -- There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) My web page: http://coyoteden.dyndns-free.com:85/gene is up! My views http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml Nothing is more admirable than the fortitude with which millionaires tolerate the disadvantages of their wealth. -- Nero Wolfe A pen in the hand of this president is far more dangerous than a gun in the hands of 200 million law-abiding citizens. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
jeremy youngs wrote: so how far does lcnc actually look ahead? One block! It always operates at a speed such that it can come to a full stop on the next G-code block. Some users who do high-speed contouring need more lookahead, and then it becomes arbitrary how far ahead you have to look. I proposed a scheme a long time ago where you would look ahead and mark points where you needed to slow down to avoid exceeding the machine's acceleration limits, then run backward through the program to a point where the slowdown needed to begin. It effectively would add an F word on every block, even when the actual G-code didn't specify one. I also posited that this couldn't be done in real time as the distance back you had to go to begin the slowdown was arbitrary. But, such an operation doesn't sound extremely difficult. Basically, you don't do anything different until you spot a block where the speed needs to be reduced below the commanded feedrate, then you have to run back to put in the lowered speed. Maintaining a queue of past moves that runs back for 100 or so blocks might make it easier to figure out where the slowdown needs to begin. Jon -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Poor CV
wow i have not used any high speed paths on my mill as its top is only 60 ipm . so i havent noticed this , but being that mastercam does exactly as you staed above i do not know if it will be an issue unless contouring . although all the programming i do at work tends to be high speed paths on machines with infinite look aheads i am certain that as my machine evolves to a higher level of performance im likey to see issues with the one block look ahead . now as i really do not wish to consider this a gripe what would it take to implement infinite look ahead ? I ask this as i prepare to move everything back to mo and see this machine actually produce for me instead of slowly get better . And i intend on doing some serious 3d profiling it could be an issue. in light of all else i do not know what the look ahead in mach is but it is highly likely this is the observed concern. thanx for the response jon On Wed, Apr 10, 2013 at 10:06 PM, Jon Elson el...@pico-systems.com wrote: jeremy youngs wrote: so how far does lcnc actually look ahead? One block! It always operates at a speed such that it can come to a full stop on the next G-code block. Some users who do high-speed contouring need more lookahead, and then it becomes arbitrary how far ahead you have to look. I proposed a scheme a long time ago where you would look ahead and mark points where you needed to slow down to avoid exceeding the machine's acceleration limits, then run backward through the program to a point where the slowdown needed to begin. It effectively would add an F word on every block, even when the actual G-code didn't specify one. I also posited that this couldn't be done in real time as the distance back you had to go to begin the slowdown was arbitrary. But, such an operation doesn't sound extremely difficult. Basically, you don't do anything different until you spot a block where the speed needs to be reduced below the commanded feedrate, then you have to run back to put in the lowered speed. Maintaining a queue of past moves that runs back for 100 or so blocks might make it easier to figure out where the slowdown needs to begin. Jon -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- jeremy youngs -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Closed loop stepping system
On 04/10/2013 07:18 AM, Javier Ros wrote: Is apparently a stepper motor that is controlled as a brushless. Essentially a stepper is a brushless. This needs a encoder, probably one with a index pulse correctly positioned, so that the electronics can compute the switching accurately. This means, even if the control of the drive looks like a STEP DIR control, internally there are position and current loops, theoretically such a drive could offer, velocity and current control (I've not checked for the above reference). The only limitations seem to be related to control at hih rpms, performance degrades in comparison with brushless. I would say that this is related to the higher pole count of the steeper, If you were to design one of these from the ground up, since position would be verified from a 10,000 step encoder, and the stepper would be run as a type of servo motor, the stepper driver would function much differently. It would generate commutation from the encoder, then it would drive a current into one coil to draw the motor towards the commanded position. PID would decide how hard to hit the motor by the difference between commanded position and current encoder position. Since this works like a servo and not a stepper with feedback, the stepper motor could be designed with less steps per rev. less steps per revolution would require less soil current reversals, and would allow the motor to step faster. If a 1mH coil standard stepper could be driven to 3000 RPM, one with 100 steps per rev instead of 200 could be driven at 6000 RPM. One with 50 steps per rev could be driven at 12000 RPM. The control circuit would have to do some tricky math to keep cogging to a minimum, but it's likely possible to make a very fast but still accurate stepper system this way. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Closed loop stepping system
On Thursday 11 April 2013 00:58:10 cogoman did opine: On 04/10/2013 07:18 AM, Javier Ros wrote: Is apparently a stepper motor that is controlled as a brushless. Essentially a stepper is a brushless. This needs a encoder, probably one with a index pulse correctly positioned, so that the electronics can compute the switching accurately. This means, even if the control of the drive looks like a STEP DIR control, internally there are position and current loops, theoretically such a drive could offer, velocity and current control (I've not checked for the above reference). The only limitations seem to be related to control at hih rpms, performance degrades in comparison with brushless. I would say that this is related to the higher pole count of the steeper, If you were to design one of these from the ground up, since position would be verified from a 10,000 step encoder, and the stepper would be run as a type of servo motor, the stepper driver would function much differently. It would generate commutation from the encoder, then it would drive a current into one coil to draw the motor towards the commanded position. PID would decide how hard to hit the motor by the difference between commanded position and current encoder position. Since this works like a servo and not a stepper with feedback, the stepper motor could be designed with less steps per rev. less steps per revolution would require less soil current reversals, and would allow the motor to step faster. If a 1mH coil standard stepper could be driven to 3000 RPM, one with 100 steps per rev instead of 200 could be driven at 6000 RPM. One with 50 steps per rev could be driven at 12000 RPM. The control circuit would have to do some tricky math to keep cogging to a minimum, but it's likely possible to make a very fast but still accurate stepper system this way. Somebody thinking outside the box, and making perfect sense. The only fly in the soup is the 10,000 step encoder, and servicing it at 200 rpS to get that 12,000 rpms, which would need to be able, if software, to do the whole control loop at a 2 megacycle rate. The best we've been able to do in software is less than 100 kilohertz at the relatively simple job of just issuing steps to the motor. These atom boards can do 50, but are hugely more comfortable running at about 47 kilohertz. To do the whole control loop at 2 megahertz to get that 12,000 rpm would need dedicated hardware that could do this in much less than .5 microseconds. I won't say its impossible, but I don't believe we have the 'state of the art', nor do we represent a sufficient economic incentive to do that as a chip design. At least not in the next calendar year. Cheers, Gene -- There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) My web page: http://coyoteden.dyndns-free.com:85/gene is up! My views http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml divorce, n: A change of wife. A pen in the hand of this president is far more dangerous than a gun in the hands of 200 million law-abiding citizens. -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
