Re: [Emc-users] Advanced bipod question
On 01.01.2015 03:16, poormansairforce H wrote: Hi all I have been trying to join the forum but can't get past the registration page, says there are errors:( I have a question about setting up a bipod hot wire cutter. Simply, in CAD I have figured out that on my dream machine setup, at a 4' 6 cutting length when the wire is angled 22.5 degrees on the vertical axis the wire moves 3mm from its intended position due to the attach points swinging in to compensate for the shortening of its length. Its obviously less then this with lesser angles but still significant when cutting wing cores, etc. On the horizontal plane it happens in 2 directions. Does LinuxCNC have skew compensation built in to account for this or can it be fixed with a config file/HAL correction??? I hope this makes senseThanks for any knowledge/answers Dan Hi Dan, happy new year, first of all ;) I have to admit that I don't quite understand what you are talking about, but it sounds like a transform problem of cartesian coordinates (XYZABCUVW in G-Code) to joint space (motor movements). In LinuxCNC, this is done by means of kinematics modules. The most basic one is trivkins, suitable for most cartesian machines (like a small XYZ mill). It simply maps each axis word (X, Y, etc.) 1:1 to the position command of the respective joint. Then there are only slightly more complicated modules, e.g. for gantry machines. And then there are the really complex beasts for serial or parallel kinematics robots. A few pre-built kinematics modules can be listed with $ man kins Maybe you can parameterize and then use the tripodkins? Otherwise it is not too hard to invent your own kinematics, as long as you can mathematically describe the forward and inverse transform and have some knowledge of C programming ;) An introduction about how to do it can be found in the docs: http://linuxcnc.org/docs/html/motion/kinematics.html And then there is the code in the source tree, which surely can serve as a template/starting point. Good luck! Regards, Philipp signature.asc Description: OpenPGP digital signature -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Possibly dumb question - 7i76 encoder for spindle speed feedback
Ok - I had an issue with the encoder scale - setting it to a fraction seems to have helped. It seems like I'm having lots of noise, though. Halscope on hm2_5i25.encoder.00.input-a gives me a nice smooth signal, but reading a spindle setting under about 500rpm gives me a reading of approx 500rpm or more. Pushing it through a limit2 seems to have smoothed the faster velocities. Above, say, 800 rpm, the system tracks quite well; up to the max of 2250rpm. I can easily tell if the machine is in low or high gear, but only when running at a requested speed of above 800 rpm. I'm going to put the 6n138 on a small bit of pc board to reduce the long leads, and see if that reduces the noise somewhat. I am confused, though, that Halscope gives me a perfect signal, but the encoder output is haywire. I guess I'm used to old-school scopes, either digital or analog screens and with real probes and stuff... On Tue, Dec 30, 2014 at 10:38 PM, Peter C. Wallace p...@mesanet.com wrote: On Tue, 30 Dec 2014, John Alexander Stewart wrote: Date: Tue, 30 Dec 2014 21:45:14 -0500 From: John Alexander Stewart ivatt...@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] Possibly dumb question - 7i76 encoder for spindle speed feedback Hi all; I'm back working on my mill with spindle tachometer, to utilize Andy Pugh's automatic spindle speed selector example code. I have, from the spindle sensor, input going to a 6N138 optoisolator's input. Ground and voltage source tied to machine. It sources enough current to drive the input quite well. (originally sent to the input of an Amtel processor in the LED spindle speed display) Output of 6N138, with +5v, ground, to the 7i76 ENCA+ and surrounding connectors on the 7i76. Looking with Halscope gives me a pretty good signal on hm2_5i25.0.encoder.00.input-a. Running at 1,000 rpm gives me 14 square teeth, running at 500 rpm gives me 7, and running at 300rpm gives me 4. (not that the counts mean much, except that the reading tracks spindle speed linearly) The 7i76 jumper is set for TTL input. ONLY the ENCA+ input pin has anything connected, the IDX, ENCB+/- and ENCA- are all left floating. The issue I have is that the velocity never seems to do much other than just futz around between 6 and 40, no matter what the spindle speed. Here's my ini code: setp hm2_5i25.0.encoder.00.counter-mode 1 setp hm2_5i25.0.encoder.00.filter 1 setp hm2_5i25.0.encoder.00.index-invert 0 setp hm2_5i25.0.encoder.00.index-mask 0 setp hm2_5i25.0.encoder.00.index-mask-invert 0 setp hm2_5i25.0.encoder.00.latch-enable 0 setp hm2_5i25.0.encoder.00.scale -16 setp hm2_5i25.0.encoder.00.vel-timeout 1.0 Should I tie the other encoder lines high/low or to somewhere? (especially the index pulse) Anybody with some advice? Thank you - John A. Stewart. If the inputs are jumpered for TTL levels you must leave the -inputs unconnected. The + inputs have 2K pullups to 5V so will be in a high state if left open. I forget the 7I76 encoder polarity but you may need to ground the ENCB+ input to get the count direction correct (ENCB is the direction input in count = COUNT/DIR mode ) -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net ___ 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. -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your
Re: [Emc-users] Possibly dumb question - 7i76 encoder for spindle speed feedback
On Thu, 1 Jan 2015, John Alexander Stewart wrote: Date: Thu, 1 Jan 2015 11:16:02 -0500 From: John Alexander Stewart ivatt...@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] Possibly dumb question - 7i76 encoder for spindle speed feedback Ok - I had an issue with the encoder scale - setting it to a fraction seems to have helped. It seems like I'm having lots of noise, though. Halscope on hm2_5i25.encoder.00.input-a gives me a nice smooth signal, but reading a spindle setting under about 500rpm gives me a reading of approx 500rpm or more. Pushing it through a limit2 seems to have smoothed the faster velocities. Above, say, 800 rpm, the system tracks quite well; up to the max of 2250rpm. I can easily tell if the machine is in low or high gear, but only when running at a requested speed of above 800 rpm. I'm going to put the 6n138 on a small bit of pc board to reduce the long leads, and see if that reduces the noise somewhat. I am confused, though, that Halscope gives me a perfect signal, but the encoder output is haywire. I guess I'm used to old-school scopes, either digital or analog screens and with real probes and stuff. It may be that you are double triggering because of noise either in the high or low states or on edges Halscope is limited in its ability to see this because of its low (servo thread rate in this case) sampling rate One option for fixing noise problems is lowering the bandwidth of the encoder input filter. The default encoder sampling rate on a 5I25 is 33.33 MHz so with filtering enabled (15 count filter) the minimum detectable pulse width is 450 nS, probably too fast for fuzzy/slow hardware like Optocouplers Im pretty sure that 2.6 has the encoder sample frequency setting available, so setting setp hm2_5i25.0.encoder.sample-frequency 50 (set encoder sample frequency to 500 KHz) for example, would now make the encoder input filter reject any pulses of less than 30 usec in duration On Tue, Dec 30, 2014 at 10:38 PM, Peter C. Wallace p...@mesanet.com wrote: On Tue, 30 Dec 2014, John Alexander Stewart wrote: Date: Tue, 30 Dec 2014 21:45:14 -0500 From: John Alexander Stewart ivatt...@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] Possibly dumb question - 7i76 encoder for spindle speed feedback Hi all; I'm back working on my mill with spindle tachometer, to utilize Andy Pugh's automatic spindle speed selector example code. I have, from the spindle sensor, input going to a 6N138 optoisolator's input. Ground and voltage source tied to machine. It sources enough current to drive the input quite well. (originally sent to the input of an Amtel processor in the LED spindle speed display) Output of 6N138, with +5v, ground, to the 7i76 ENCA+ and surrounding connectors on the 7i76. Looking with Halscope gives me a pretty good signal on hm2_5i25.0.encoder.00.input-a. Running at 1,000 rpm gives me 14 square teeth, running at 500 rpm gives me 7, and running at 300rpm gives me 4. (not that the counts mean much, except that the reading tracks spindle speed linearly) The 7i76 jumper is set for TTL input. ONLY the ENCA+ input pin has anything connected, the IDX, ENCB+/- and ENCA- are all left floating. The issue I have is that the velocity never seems to do much other than just futz around between 6 and 40, no matter what the spindle speed. Here's my ini code: setp hm2_5i25.0.encoder.00.counter-mode 1 setp hm2_5i25.0.encoder.00.filter 1 setp hm2_5i25.0.encoder.00.index-invert 0 setp hm2_5i25.0.encoder.00.index-mask 0 setp hm2_5i25.0.encoder.00.index-mask-invert 0 setp hm2_5i25.0.encoder.00.latch-enable 0 setp hm2_5i25.0.encoder.00.scale -16 setp hm2_5i25.0.encoder.00.vel-timeout 1.0 Should I tie the other encoder lines high/low or to somewhere? (especially the index pulse) Anybody with some advice? Thank you - John A. Stewart. If the inputs are jumpered for TTL levels you must leave the -inputs unconnected. The + inputs have 2K pullups to 5V so will be in a high state if left open. I forget the 7I76 encoder polarity but you may need to ground the ENCB+ input to get the count direction correct (ENCB is the direction input in count = COUNT/DIR mode ) -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net
[Emc-users] linuxcnc-sim on Mint 17.1 LTS
Greetings, and I hope everyone will have a better year in 2015; Mint 17.1 LTS with cinnamon gui has arrived, called Rebecca. It looks decent enough but the synaptic shipped for a package manager, is quite broken. No mark all updates button for starters, and while it does identify a group of packages as being upgradeable, the only action offered is to remove them when you click on them. Bummer. Aptitude fares little better, mostly because I long ago forgot how to run it. Adding the line for the buildbot so I could install the master-sim, lucid as a repo refuses because most of the python etc stuff is newer so it fails even though it says =1.40 for the dependency and its 1.55 installed. Going to the web page, I find several other names I can switch in for Lucid, but I've never tracked a distro by name, so other than 8.04 being Hardy (I think) I am lost. Lucid can see the sim but will not allow it to be installed. Precise can't even see it. So I need some guidance I believe, or should I wipe and install ubu-14.4 LTS in some flavor. Scary, the reports are that it is also severely broken, with won't even boot at the top of the lists I am seeing. Trying to do this because there is only a few more months of support left for the 10.04.4 LTS server editions now, and its time to update the OS itself. I have also about worn out the i386 model since I have a quad core 64 bit phenom, and the 64 bit versions of stuff like firefox run a heck of a lot faster. So, what amd64 flavor of Ubuntu stands the best chance of working with the existing repo's? And which name do I then put in /etc/apt/sources.list? Thanks all. Cheers, Gene Heskett -- There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) Genes Web page http://geneslinuxbox.net:6309/gene US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] CNC Workshop 2015
The CNC workshop will return in June of 2015. This is the continuation of the event started more than 10 years ago by Roland Friestad, then later run by DIGITAL MACHINIST magazine. This year the workshop will be held at the TechShop in Allen Park Michigan, between Detroit and Ann Arbor. the location is very convenient to the Detroit area, the Detroit airport, and just across the road from the Henry Ford Museum. The workshop will run between June 15 and 20, with the main session opening Wednesday morning, June 17. This year the format will be similar to the past years- we will have 3 days of continuous seminars about CNC aimed at the home shop user. We have classrooms ranging from a tiered auditorium for over 150 people to small conference rooms. We will have an area for commercial vendors to show their products, and an area for individuals to exhibit their projects. We are now seeking people that want to present a seminar session, or exhibit their project. Speakers and exhibitors will receive a discount on the registration fee. TechShop has setup a web form to collect input at http://tinyurl.com/techshopcncworkshop. Please use the form to get your name on the list for further information and to let us know what you are willing to present, or what you would like to hear about. An added feature this year will be 2 days reserved for special, in-depth training session. TechShop will be offering selected training on using various machines, and we may have vendor specific training. These sessions will be on Monday and Tuesday before the main Workshop sessions begin. There may be an additional charge for these sessions. Please let us know on the information form of your interest in any in-depth training. A build class, based on the micro mill from LittleMachineShop.com and led by Weston Bye will be included. This session is limited to 12 people, so if you are interested in building your own CNC mill please let us know quickly. Registration will open about February 1. Please use the information form to get your name on the list and to tell us what you would like to see and hear at the workshop. I hope we can make this years workshop even better than those of the previous years. Please let us know of your interest so we can plan the best workshop ever. -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Advanced bipod question
On 1 January 2015 at 02:16, poormansairforce H poormansairfo...@gmail.com wrote: I have been trying to join the forum but can't get past the registration page, says there are errors:( You will get better answers here anyway. I have a question about setting up a bipod hot wire cutter. Simply, in CAD I have figured out that on my dream machine setup, at a 4' 6 cutting length when the wire is angled 22.5 degrees on the vertical axis the wire moves 3mm from its intended position due to the attach points swinging in to compensate for the shortening of its length. I don't quite get what you are saying. Is this an effect in addition to the simple calculations in the kinematics module? Can you expand the its into the actual components being discussed? Maybe you are looking at the effect of the pulley diameter not being infinitesimal? -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] linuxcnc-sim on Mint 17.1 LTS
On 01/01/2015 10:12 PM, Sebastian Kuzminsky wrote: On 01/01/2015 08:59 PM, Gene Heskett wrote: So, what amd64 flavor of Ubuntu stands the best chance of working with the existing repo's? And which name do I then put in /etc/apt/sources.list? I run LinuxCNC on Ubuntu Precise (12.04) on some of my machines. I'm not a fan of the Ubuntu UI, but it works. Instructions here: You can make 12.04 revert to the Gnome Classic desktop. The only problem I had was the window borders were too narrow to grab for resizing, there is a hack that requires editing the metacity theme file. if anyone needs to know how to do this, just email me. Jon -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] linuxcnc-sim on Mint 17.1 LTS
On 01/01/2015 08:59 PM, Gene Heskett wrote: So, what amd64 flavor of Ubuntu stands the best chance of working with the existing repo's? And which name do I then put in /etc/apt/sources.list? I run LinuxCNC on Ubuntu Precise (12.04) on some of my machines. I'm not a fan of the Ubuntu UI, but it works. Instructions here: http://www.linuxcnc.org/docs/2.7/html/getting-started/index.html#_installing_on_ubuntu_precise I personally prefer Debian Wheezy, which works out of the box using the new Live/Install Image. Instructions for that are here: http://www.linuxcnc.org/docs/2.7/html/getting-started/index.html#_getting_linuxcnc -- Sebastian Kuzminsky -- Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Possibly dumb question - 7i76 encoder for spindle speed feedback
On Thursday 01 January 2015 11:16:02 John Alexander Stewart did opine And Gene did reply: Ok - I had an issue with the encoder scale - setting it to a fraction seems to have helped. It seems like I'm having lots of noise, though. Halscope on hm2_5i25.encoder.00.input-a gives me a nice smooth signal, but reading a spindle setting under about 500rpm gives me a reading of approx 500rpm or more. Pushing it through a limit2 seems to have smoothed the faster velocities. Above, say, 800 rpm, the system tracks quite well; up to the max of 2250rpm. I can easily tell if the machine is in low or high gear, but only when running at a requested speed of above 800 rpm. I'm going to put the 6n138 on a small bit of pc board to reduce the long leads, and see if that reduces the noise somewhat. I am confused, though, that Halscope gives me a perfect signal, but the encoder output is haywire. I guess I'm used to old-school scopes, either digital or analog screens and with real probes and stuff... I have come to the conclusion that for such as this, the halscope isn't always telling us the truth. And I believe the timing jitters we are seeing are an artifact of a finite sampling period, which is relatively short, so a one count ambiguity represents a rather large amount of noise when the software is doing the sampling. Putting a 5i25 in my lathe setup reduced it a lot, but the ideal situation is not available in the modules directory for LCNC. IMO a shift register, at least 16 bits or more wide, and 4 shift stages would be ideal, each register summed with a gain of .25, which should balance out any cyclic/mechanical irregularities. I suppose one could coble something up and halcomp it just to prove the point, but that wouldn't drop my minimum rpm enough to make a huge difference. Currently I am good down to about 200-250 revs before it gets to hammering the backgears too badly. Before the 5i25, it was hammering the backgears at 5 or 600 revs, but with the 5i25 I can triple the PGain, making it pretty stiff even at 175 revs. On Tue, Dec 30, 2014 at 10:38 PM, Peter C. Wallace p...@mesanet.com wrote: On Tue, 30 Dec 2014, John Alexander Stewart wrote: Date: Tue, 30 Dec 2014 21:45:14 -0500 From: John Alexander Stewart ivatt...@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] Possibly dumb question - 7i76 encoder for spindle speed feedback Hi all; I'm back working on my mill with spindle tachometer, to utilize Andy Pugh's automatic spindle speed selector example code. I have, from the spindle sensor, input going to a 6N138 optoisolator's input. Ground and voltage source tied to machine. It sources enough current to drive the input quite well. (originally sent to the input of an Amtel processor in the LED spindle speed display) Output of 6N138, with +5v, ground, to the 7i76 ENCA+ and surrounding connectors on the 7i76. Looking with Halscope gives me a pretty good signal on hm2_5i25.0.encoder.00.input-a. Running at 1,000 rpm gives me 14 square teeth, running at 500 rpm gives me 7, and running at 300rpm gives me 4. (not that the counts mean much, except that the reading tracks spindle speed linearly) The 7i76 jumper is set for TTL input. ONLY the ENCA+ input pin has anything connected, the IDX, ENCB+/- and ENCA- are all left floating. The issue I have is that the velocity never seems to do much other than just futz around between 6 and 40, no matter what the spindle speed. Here's my ini code: setp hm2_5i25.0.encoder.00.counter-mode 1 setp hm2_5i25.0.encoder.00.filter 1 setp hm2_5i25.0.encoder.00.index-invert 0 setp hm2_5i25.0.encoder.00.index-mask 0 setp hm2_5i25.0.encoder.00.index-mask-invert 0 setp hm2_5i25.0.encoder.00.latch-enable 0 setp hm2_5i25.0.encoder.00.scale -16 setp hm2_5i25.0.encoder.00.vel-timeout 1.0 Should I tie the other encoder lines high/low or to somewhere? (especially the index pulse) Anybody with some advice? Thank you - John A. Stewart. If the inputs are jumpered for TTL levels you must leave the -inputs unconnected. The + inputs have 2K pullups to 5V so will be in a high state if left open. I forget the 7I76 encoder polarity but you may need to ground the ENCB+ input to get the count direction correct (ENCB is the direction input in count = COUNT/DIR mode ) - - Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software