#emc | Logs for 2009-10-21

[00:10:36] <Neo_The_User> I found a list in magma but its way out of date
[00:13:54] <SWPadnos> Neo_The_User, I don't know that there is a comprehensive list of "what doesn't work"
[00:14:22] <Neo_The_User> so there is a chance that will work fine?
[00:14:24] <SWPadnos> there are a few kernels/RTAI versions that had specific problems, and so were labeled "stay away"
[00:14:30] <SWPadnos> there's a chance
[00:14:36] <SWPadnos> is there a patch for it?
[00:14:42] <Neo_The_User> not in magma
[00:14:47] <SWPadnos> ok
[00:15:08] <Neo_The_User> and I have an ext4 filesystem so.. I can't settle for old kernels
[00:15:17] <SWPadnos> heh
[00:17:12] <SWPadnos> I don't think you have to use magma
[00:17:21] <SWPadnos> wasn't that just the 3.2 series name or something?
[00:17:24] <jymm> SWPadnos: HDTV's.... is 120Hz that much better than 60Hz?
[00:17:31] <SWPadnos> jymm, no idea
[00:17:34] <jymm> k
[00:17:43] <Neo_The_User> jymm: for your eyes, no
[00:17:43] <SWPadnos> I haven't seen any problems with my 60 Hz one
[00:17:54] <Neo_The_User> your eyes can't pick up differences like that IIRC
[00:18:30] <SWPadnos> the only place where it would be significantly better is that a 120Hz screen is guaranteed to be able to play 24 and 30 FPS content at an even multiple of the original
[00:18:40] <SWPadnos> so there's no 3:2 pulldown for movies
[00:18:49] <Neo_The_User> ah good point
[00:18:55] <jymm> I'm think about getting one of these... http://www.walmart.com/Vizio-32-1080p-LCD-Java/ip/10778775
[00:19:21] <jymm> *ing
[00:19:21] <SWPadnos> also, if you ever want to use a 3d video or game that supports it, the 120Hz rate is necessary so you get the full 60 Hz in both eyes
[00:19:24] <SWPadnos> the Vizio TVs are really good, that's what I bought
[00:19:52] <jymm> Ok, that's what I heard.
[00:20:01] <SWPadnos> they're mde in CA as well
[00:20:02] <jymm> glad you were able to confim
[00:20:03] <SWPadnos> made
[00:20:16] <jymm> CAnada or CAlif ?
[00:20:23] <SWPadnos> California
[00:20:26] <jymm> k
[00:20:45] <SWPadnos> you can actually buy locally made Blu-ray players (Oppo) and TVs (Vizio)
[00:20:57] <SWPadnos> and the Oppo is the best on the market, bar none
[00:21:41] <jymm> Hmmm 3yr walmart warranty $45
[00:21:55] <Neo_The_User> The current blu ray players are terrible. The PS3 is the most stable player
[00:21:56] <SWPadnos> Costco has the same model for $429.99
[00:22:08] <SWPadnos> Neo_The_User, that was true, until the Oppo BDP-83 came out
[00:22:18] <Neo_The_User> never heard of it
[00:22:35] <SWPadnos> http://www.oppodigital.com/blu-ray-bdp-83/
[00:23:24] <SWPadnos> plays every kind of disc that fits in it (possibly excepting CD-V), and does an excellent job with all of them
[00:23:28] <jymm> You think an extended warranty on this is a good thing?
[00:23:40] <jymm> SWPadnos: does it play ISO's?
[00:23:41] <SWPadnos> has the best DVD upscaling available, and also the best Blu-ray native playback
[00:23:56] <SWPadnos> err - no, I don't think so
[00:24:08] <SWPadnos> but you can plug in a USB storage device and play mp3/mp4 files from it
[00:24:34] <SWPadnos> and I don't believe it will stream via ethernet at the moment either
[00:24:42] <jymm> SWPadnos: bummer.
[00:25:12] <SWPadnos> I don't know about the warrantee
[00:25:32] <SWPadnos> I'd get it at Costco - I think they sell extended warranties as well, and I'd trust them better
[00:25:33] <jymm> I ask, becasue I have nfc on the lifespan of LCD TV's
[00:25:39] <SWPadnos> long time
[00:25:57] <jymm> I hear mixed horor stories.
[00:26:10] <SWPadnos> the CCFL can get dim over time, but that usually takes several years to get to half brightness
[00:26:52] <SWPadnos> and you can just turn up the brightness when that happens, so I'd expect an LCD to last quite a long time
[00:27:58] <jymm> SWPadnos: I mean MTBF
[00:28:22] <SWPadnos> the only thing that isn't completely solid state is the CCFL supply/tube
[00:28:28] <SWPadnos> so I'd expect it to last a long time
[00:28:57] <SWPadnos> I haven't seen a single LCD screen die, even going back to my (well beaten) laptop that I bought in 2001
[00:29:29] <SWPadnos> and a home TV would be expected to last a bit longer, since they theoretically don't get moved around as much
[00:29:43] <jymm> dead/frozen pixels, driver, etc
[00:29:56] <SWPadnos> sure
[00:30:06] <jymm> it even mirrors the mfg warranty for in-home service
[00:30:07] <SWPadnos> I'd check the warrantee though, it may not cover dead pixels
[00:30:54] <SWPadnos> oh hmmm - the ones at Costco aren't 1080p
[00:31:12] <jymm> really? that's surprising
[00:31:17] <Dave911> alex_joni: >>>this is amusing: "I was under the impression that Mach was first developed by Canada's goverment or the first 80% and released to the public...then finished by Artsoft...so emc may share the same core but did not actually write it"
[00:31:19] <Dave911> I was told that Art got the NIST source code as did some other people when it was released. Art is an old time hacker. He is a very clever guy but he has no formal programming training that I know of. He wanted to create a CNC controller so he could cut jewelry and jewelry molds with it. He wanted to run it on Windows. That was how it started. It then grew, other people heard about his...
[00:31:20] <Dave911> ...work, he gave away some copies and then started charging for them, and it evolved. I think it started with Master5, then Mach2 and Mach3. The real gem of Mach3 is the LPT driver. Everything else is a Windows App that tortures windows into functioning as a CNC controller. I don't believe the Canadian Gov had anything to do with the origins of Mach3. It was truly Art's baby.
[00:31:21] <SWPadnos> the cheap ones aren't - they have them of course
[00:31:56] <SWPadnos> NIST -> ARt -> Mach
[00:31:59] <SWPadnos> Art
[00:32:14] <jymm> SWPadnos: Ah, Well, I think a trip to walmart this evening s in order =)
[00:32:24] <SWPadnos> I think Ray is the one who originally handed Art the disk :)
[00:34:20] <Dave911> >>I think Ray is the one who originally handed Art the disk :)
[00:34:21] <Dave911> I bet that Art remembers who he got it from! ;-)
[00:34:52] <SWPadnos> heh, could be
[00:35:07] <SWPadnos> did you read the silly thread those comments came from?
[00:35:44] <Dave911> Yes, typical hearsay crap.. Notice that no one has actually tried to load and run the sw... :-(
[00:35:51] <SWPadnos> yeah
[00:36:08] <SWPadnos> I was going to post a somewhat more informed reply, but I'm not a member
[00:36:13] <SWPadnos> and it wasn't worth signing up
[00:36:43] <Dave911> It really has nothing to do with EMC2, it really has to do with people fear of Linux.
[00:37:04] <SWPadnos> yeah, tell me about it
[00:38:08] <SWPadnos> it's funny - I think someone posted on Slashdot (in an Android discussion, which turned into an iphone vs android discussion ...) that people find macs easier to use because they think they're easier to use, so they don't get scared if something doesn't work, and they figure it out
[00:38:16] <Dave911> Ubuntu is so "windows compatible" in functionality it is crazy....
[00:38:21] <SWPadnos> yes
[00:39:16] <SWPadnos> and there was an interesting poece on NPR over the weekend (I think), where they talked about the "race gap" or "gender gap" in school testing more or less disappearing when they rephrase the description of the test
[00:39:51] <SWPadnos> piece
[00:40:12] <SWPadnos> it seems that a lot of it (Linux related) is initial (mis)perception
[00:40:48] <Dave911> My wife is a college prof and she talks about stuff like that a lot... aim the test at a certain audience and they can do and the fringes of the audience do not..
[00:41:12] <SWPadnos> yep
[00:41:30] <SWPadnos> when you think something is skewed against you, you give up earlier, since there must be no way to win
[00:42:35] <Dave911> I think it is primarily a US things with Windows. I was trying to sell a industrial PC made by Siemens on Ebay - I got a guy from India who was interested but he had not desire to buy the included software. He said they only use Linux in India. While I'm sure that is a generalization, it is apparently much more prevalent over there than here..
[00:43:47] <SWPadnos> I think there are sectors everywhere that use Linux a lot, but it's not really in the news
[00:44:04] <SWPadnos> unless it's something like Home Depot switching from Windows to Linux (and then back)
[00:44:40] <SWPadnos> I was just reading that on Hollywood, Linux is it - all the production houses use it for basically all their servers, most of their computing, and lots of their workstations
[00:44:54] <SWPadnos> but they all have macs in the front office
[00:46:08] <Dave911> I think that Linux is being used by the military.. but I don't know the ratio of Windows to Linux boxes..
[00:46:48] <SWPadnos> backend = Linux, frontend = windows
[00:48:15] <Dave911> Doesn't that sort of mirror the rest of the US - most of the web = Linux, most desktops = Windows
[00:48:30] <SWPadnos> yeah, I think that's a common mode
[00:50:02] <Neo_The_User> does anybody know where --with-realtime=<path> is supposed to link to? i linked it to the kernel source and didn't work
[00:50:29] <SWPadnos> that's an EMC2 build thing
[00:50:36] <SWPadnos> oh - duh
[00:50:59] <SWPadnos> did you build RTAI after building the ADEOS/ipipe enabled kernel?
[00:51:30] <Neo_The_User> No I patched my kernel with the -tip tree from igno molnar
[00:52:03] <SWPadnos> that won't work
[00:52:34] <SWPadnos> unless you've added an RTAPI layer to EMC2 that supports that type of kernel
[00:53:03] <Neo_The_User> I didn't modify the source from hand, no
[00:53:42] <SWPadnos> you would have had to write it yourself, actually
[01:09:53] <L84Supper> now I see where all the work has to go into RTAI support :)
[04:32:21] <tom3p> i needed to make some bash scripts more gui, like get a data file for the command. 'zenity' is very cool for this.
[06:37:48] <mindThomas> Hi
[06:37:57] <mindThomas> Anyone in here, who is alive?
[06:40:15] <MrSunshine_> no, im quite dead i think
[06:40:30] <mindThomas> :D
[06:40:38] <mindThomas> I'm new in this LinuxCNC thing
[06:40:54] <mindThomas> But I've got a 6DOF robot, which I want to do some Inverse Kinematics with
[06:41:06] <mindThomas> Is that possible with LinuxCNC?
[06:42:17] <MrSunshine_> i dont know at all :) all ive done with emc is running my small first mill i built :P
[06:44:39] <micges_work> mindThomas: emc has kinematics for serial and parraller robots
[06:45:25] <micges_work> It is possible to control robots with emc
[06:45:38] <mindThomas> I've got this robot
[06:45:39] <mindThomas> http://www.arexx.com.cn/EnProductShow.asp?ID=123
[06:45:47] <mindThomas> And it's controlled with Serial commands
[06:47:06] <micges_work> with rs232?
[06:47:52] <micges_work> mindThomas: via serial port?
[06:48:34] <MrSunshine_> its a serial port connector on the card so i guess it should be rs232 serial port yes :P
[06:48:46] <MrSunshine_> but what do i know :)
[06:49:29] <mindThomas> yes
[06:49:31] <mindThomas> it's RS232
[06:49:42] <mindThomas> but I'm using a laptop, so I've got a USB to RS232 (FTDII)
[06:49:48] <mindThomas> *(FTDI)
[06:52:34] <mindThomas> But isn't it difficult to set ENC2 up to control my robot with World Based cordiates (XYZABC - which is inverse kinematics)
[06:54:57] <micges_work> that part is called kinematics, translate world coordinates to motors coordianates
[06:55:26] <micges_work> emc has one called genserkins (general serial robots kinematics)
[06:57:19] <micges_work> MrSunshine_: I missed that on pic, I've focused on counting DOF on robot ;)
[06:57:50] <MrSunshine_> micges_work, heh =)
[06:58:29] <micges_work> mindThomas: what commands you sending via serial port? gcode? position?
[06:58:34] <micges_work> velocity?
[06:59:26] <mindThomas> it's a 6DOF robot
[06:59:40] <mindThomas> Which I've got from the university I'm on
[06:59:55] <mindThomas> It's a school project I'm working on, so it would be great if you could help me
[07:00:15] <mindThomas> the serial commands are strange NON-Standard commands
[07:00:27] <MrSunshine_> but isnt the USB -> Serial a problem for emc ?
[07:01:34] <mindThomas> Please see page 15 in this PDF: http://www.arexx.com.cn/uploadfiles/6servo_robot_arm_eng.pdf
[07:03:46] <micges_work> heh another chinese supa program ;)
[07:04:21] <micges_work> (I've ripped all control programs from chinese machines and put there emc ;)
[07:04:45] <micges_work> and (suprisely) they're works better :D
[07:08:09] <micges_work> mindThomas: I think you can put emc instead of this control program but for some details you must wait for alex_joni and ask him(he is out at the moment)
[07:08:23] <micges_work> must back to work, bbl
[07:14:17] <mindThomas> When will alex_joni join?
[07:16:29] <micges_work> probably evening (he has got 10:15 time now)
[07:16:49] <mindThomas> I've got 9:16
[07:16:54] <micges_work> me too
[07:17:02] <mindThomas> where you from?
[07:17:31] <micges_work> I'm from Poland
[07:17:41] <mindThomas> ohh
[07:19:26] <micges_work> and you ?
[07:19:40] <mindThomas> Denmark
[07:21:29] <alex_joni> * alex_joni is around now
[07:44:15] <alex_joni> mindThomas: you can do forward/inverse kins in emc2 for that robot
[07:44:46] <alex_joni> mindThomas: you would have to rip out the electronics from the robot, and directly drive the motors (using step controllers) from emc2 to make it work
[07:55:10] <mindThomas> Hi alex_joni
[07:55:13] <mindThomas> sorry for the late reply
[07:55:34] <mindThomas> The robot is using Servo's
[07:55:53] <alex_joni> ok, then servo controllers
[07:56:07] <alex_joni> emc2 isn't suited communicating with "smart" hardware using serial protocols
[07:56:34] <mindThomas> so?
[07:56:52] <alex_joni> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Emc2HardwareDesign
[07:56:55] <mindThomas> I'm using a laptop
[07:56:55] <MrSunshine_> gah i want moneys now! :)
[07:57:07] <mindThomas> Why MrSunshine :)
[07:57:08] <alex_joni> mindThomas: then emc2 won't work
[07:57:20] <mindThomas> serious?
[07:57:28] <mindThomas> Do you need to use a parallel port?
[07:57:41] <alex_joni> first of all, you need a proper PC for realtime
[07:57:45] <alex_joni> laptops are crappy for that
[07:57:48] <MrSunshine_> mindThomas, to buy steppers controller and powersupply for my mill =)
[07:58:05] <alex_joni> (because of all the 'smarts' inside: cpu speed throttling, etc)
[07:58:45] <MrSunshine_> cpu speed throttling can be disabled? :)
[07:58:45] <mindThomas> ohh, but I can make another RS232 board myself
[07:58:48] <MrSunshine_> to always go max ? :)
[07:59:08] <mindThomas> cpu speed throttling, on a laptop?
[07:59:12] <mindThomas> is that what you are talking about?
[07:59:21] <MrSunshine_> aye
[07:59:29] <MrSunshine_> but isnt that in stationary pcs also ? :)
[07:59:45] <mindThomas> alex_joni? also when it is plugged into a power supply?
[08:01:46] <alex_joni> MrSunshine_: not completely
[08:01:54] <alex_joni> thermal design is also a problem
[08:02:07] <alex_joni> I've seen laptops which cause a huge latency spike when the CPU cooler turned on
[08:02:23] <MrSunshine_> hmm
[08:02:25] <MrSunshine_> ok :)
[08:02:28] <alex_joni> which is something you couldn't change
[08:02:53] <alex_joni> but these are just 2 examples of things that can happen.. there are virtually dozens inside a laptop
[08:02:58] <mindThomas> but remember
[08:03:01] <alex_joni> you might be lucky and it works, or you might not
[08:03:05] <mindThomas> this is only for educational purposes
[08:03:11] <alex_joni> mindThomas: that's irrelevant
[08:03:21] <mindThomas> the robot should only grab a thing and move it around
[08:03:27] <mindThomas> it doesn't have to be fast
[08:03:32] <alex_joni> a non-working system isn't any good for educational purposes
[08:03:39] <alex_joni> even for educational purposes
[08:03:57] <alex_joni> move it around in world coords?
[08:04:00] <alex_joni> e.g. carthesian?
[08:04:33] <alex_joni> I see 3 possible ways to fix it.. just a moment
[08:08:22] <alex_joni> ok.. back
[08:08:39] <alex_joni> 1. fix emc2 to make it work with a serial connection to a smart controller
[08:08:59] <alex_joni> 2. change your hardware so that emc2 interfaces directly with the motor controller and reads the feedback
[08:09:17] <alex_joni> 3. write a custom app that sends position to the robot and makes it move where it should
[08:09:53] <alex_joni> 1 - you need extensive knowledge of emc2, and probably 3-4 months of work (the outcome is not sure, it might not be possible)
[08:10:18] <alex_joni> 2 - you need hardware: PC + control board + motor drives (some you might build, some you might buy)
[08:10:28] <alex_joni> 3 - probably the simplest, but needs some coding
[08:11:52] <mindThomas> I've got alot of programming, so I know programming in both Visual C++ and C for microcontrollers such as AVR and PIC
[08:12:13] <mindThomas> The servo's on the robot i've got doesn't give any feedback
[08:12:40] <mindThomas> as Servo's are positioning to the correct place, they don't have to give any information back, like the steppers
[08:17:05] <MrSunshine_> hmm
[08:17:19] <MrSunshine_> well isnt just like 1uS off going to put it in the wrong position ?
[08:17:25] <MrSunshine_> and then the next 1uS next time
[08:17:30] <MrSunshine_> etc and that piles up
[08:17:33] <MrSunshine_> thats why you have feedback
[08:18:03] <MrSunshine_> steppers also "need" feedback to correctly be able to position time after time .. specialy at load
[08:18:08] <mindThomas> 1uS, what are you talking about?
[08:18:11] <MrSunshine_> so steppers arent a sure deal :)
[08:18:16] <MrSunshine_> mindThomas, or ms or whatever
[08:18:21] <mindThomas> i know
[08:18:28] <MrSunshine_> as you pulse to the servo for a given time and it moves a given distance
[08:18:33] <mindThomas> but with the RS232 board I have
[08:18:40] <mindThomas> you just send the specific position
[08:18:55] <mindThomas> and the board takes care of the correct pulsing, not the computer :)
[08:19:04] <MrSunshine_> true
[08:24:43] <alex_joni> mindThomas: then you might hack emc2 .. maybe
[08:24:49] <alex_joni> you use a sim-only configuration
[08:25:00] <alex_joni> and take the current joint positions and send them through serial
[08:25:03] <alex_joni> and hope for the best
[08:25:20] <alex_joni> (you can do this by writing a HAL userspace component)
[08:25:29] <alex_joni> it might probably be fastest/easiest in python
[08:41:40] <micges_work> mindThomas: I was also thinking about this solution
[09:11:22] <mindThomas> hmm
[09:11:37] <mindThomas> I haven't dealt with Python before
[09:11:47] <mindThomas> In school we normally doesn't use Linux
[09:11:55] <mindThomas> therefor I don't know much about Linux programming
[09:12:06] <mindThomas> I just saw ENC2 used in youtube video
[09:12:19] <mindThomas> and then I thought that might be the thing I was looking for
[10:10:28] <MattyMatt> is it worth replacing the bearings in a Black & Decker? this one is bullshit
[10:43:22] <AchiestDragon> i stoped buying b&d stuff years back because of the rather weak build quality ,, probablay better to replace the lot with a better make
[10:43:56] <MattyMatt> that meddings woulda done me :)
[10:44:41] <AchiestDragon> at the local car boot sale they ofen sell the nikita and such ex contracter drills etc ,, used with the bearings near end of life ,, now they would be worth replacing and reparing for home use
[10:45:15] <AchiestDragon> a b&d one used in the same environment as they where would not last a week
[10:45:27] <MattyMatt> if I can find one of them with no hammer action and a 44mm collar, I'll be happy
[10:45:54] <MattyMatt> I do have an ancient 140W B&D but it won't fit in this press
[10:46:02] <AchiestDragon> on the ones i have seen the hanner action is selectable
[10:46:07] <AchiestDragon> hammer
[10:46:41] <MattyMatt> yeah and momma selects it until it all turns to cheese
[10:47:14] <AchiestDragon> the bosh one i have had that for over 20 years ,, the chuck bearings are just starting to go in it
[10:47:27] <MattyMatt> this is the drill she & my sis "poke holes in walls" with (with my HSS bits often as not)
[10:50:32] <MattyMatt> argh I thought I was winning when I got this drill stand instead of a proper press. the stand is lovely but now I gotta look for a drill
[11:15:10] <MattyMatt> mindThomas: is it the emc GUI you want for your robot? with all the jog buttons and DRO type stuff?
[11:31:21] <undrill> bosh, nikita? What are these brands?
[11:40:55] <MattyMatt> bosch & makita. if it's readable it's good :)
[11:43:19] <MattyMatt> damn I wish this ancient B&D had a 44mm collar, the bearings are lovely
[11:44:46] <undrill> ah yes, makita, not nikita, as in kruschev
[11:45:46] <undrill> I have a bosch angle grinder that is ancient
[12:07:42] <AchiestDragon> seems that complaning about people picking on others about spelling and typos just provokes them
[12:07:52] <AchiestDragon> do do it more
[12:08:19] <AchiestDragon> fuck it can see that its done on perpouse godbye
[12:09:05] <AchiestDragon> fuck it can see that its done on perpouse goodbye even since you cant stand errors and when you make some then dont expect to be treat any better than you have done
[12:09:15] <MrSunshine_> haha
[12:09:23] <MrSunshine_> ok that guy REALY needs anger management
[12:36:02] <mhaberler> quick question - how do I determine max velocity and max acceleration with a hm2 configuration? stepconf can do it but only for parports it seems
[12:36:39] <SWPadnos> are you asking how to determine what the motors can do, so that you can enter the correct values into your ini file?
[12:37:06] <SWPadnos> or now to tell what the limits are set to, from the ini file and stepgen parameters?
[12:37:10] <SWPadnos> s/now/how/
[12:38:54] <mhaberler> I'm trying to figure what the motors can do in a hm2 stepper setup, so I can fill in the ini file with realistic values instead of looking into my crystal ball
[12:39:06] <SWPadnos> ok :)
[12:39:33] <SWPadnos> the motors/drives will be the limiting factor, so thisis a mechanical question
[12:39:44] <SWPadnos> what drivers are you using?
[12:40:26] <mhaberler> these are mechapro.de HPStep 4xmicrostepping, can do 4.5 amps, currently at 3 amps or so
[12:41:11] <mhaberler> maybe excising the max velocity/accel test from stepconf is a way to do it
[12:41:38] <SWPadnos> yes, that's one way to do it
[12:41:59] <mhaberler> so the hm2 stepper folks are all guessing, right :-?
[12:42:18] <SWPadnos> it's likely that the mesa stepgen can generate steps faster than the driver can handle them, and way faster than the motor can turn
[12:42:25] <SWPadnos> no
[12:42:46] <mhaberler> yes, it can
[12:43:18] <SWPadnos> you can set up a bare HAL test environment, similar to what the stepgen test does
[12:43:28] <SWPadnos> err - stepconf
[12:43:36] <mhaberler> yes, that looks like my night shift project
[12:43:55] <SWPadnos> I believe stepconf uses a limit2 block for accel / vel limiting, and a siggen to output a square wave
[12:44:11] <mhaberler> ok, will dive into da code
[12:44:16] <SWPadnos> the limits can be tweaked while the system is running
[12:45:06] <SWPadnos> I don't know if there's a standalone HAL file, but there ought to be one, with a pyvcp panel to set the limits
[12:46:21] <mhaberler> hm, another way to more reliably detect step loss would be a probe - touch off, move away slowly to safe distance, accelerate/move back fast and then probe again to see wether the values match
[12:46:29] <jthornton> couldn't you just tweak the settings in axis in the Show HAL Configuration window then write down the best settings and change your ini
[12:46:37] <SWPadnos> you don't need that much information
[12:46:44] <SWPadnos> you'll hear if a stepper stalls
[12:47:11] <SWPadnos> and that's what you want to get to - use a relatively low max velocity and increase acceleration until the steppers stall
[12:47:30] <SWPadnos> then back off some amount (maybe as low as 50% of the stall accel)
[12:47:41] <mhaberler> good point - we're back to my "aural probe concept"
[12:47:54] <SWPadnos> once you have the accel set, you can increase the velocity until you hear the steppers stall at full speed
[12:48:10] <SWPadnos> doing that, you need to have moves long enough to get up to full speed (whatever that is at the time)
[12:48:23] <SWPadnos> yes, your ears are good at detecting problems :)
[12:48:58] <mhaberler> ok, I'll give it a stab - thanks a lot
[12:48:59] <SWPadnos> jthornton, yes and no - the TP only loads accel/vel limits at startup, so you can't change that with "Show HAL"
[12:49:04] <SWPadnos> sure
[12:49:14] <jthornton> ok, didn't know that part
[12:51:02] <SWPadnos> mhaberler, if you look at the stepconf source, there is a function called "test_axis", which contains the text you would want to start with in a bare HAL setup
[12:51:17] <SWPadnos> it's at line 1492 in the current git version
[12:52:18] <SWPadnos> the line "halrun.write (""" ... is the beginning
[12:53:03] <SWPadnos> hmmm. then again, that would need a lot of massaging to get it to work for mesa, so maybe starting from scratch might be better
[12:56:57] <jthornton> mhaberler: you can tune your mesa setup from pcconf if you have dev
[12:57:41] <jthornton> s/pcconf/pncconf
[12:58:05] <cradek> mhaberler: are these plots from a hm2 stepper system? http://mah.priv.at/cgi-bin/viewvc.cgi/emc-syncmove/45ppr-accel300-dampened-oscillation.png?revision=1.1&root=CVS&view=markup
[12:58:47] <cradek> I'm asking because I don't understand why you have this kind of ferror
[12:59:55] <cradek> it has nothing to do with threading. it seems like a step generator setting?
[13:00:47] <cradek> I mean I bet you see these kinds of ferrors for all moves.
[13:01:42] <cradek> the threading issue is whether the purple line is straight - and it looks straight to me
[13:02:16] <cradek> last night (US) there was lots of discussion on #emc-devel about this issue - you might want to read those logs
[13:06:10] <tom3p> re: mindThomas and the 6dof robot..
[13:06:21] <tom3p> the pics and the command format "# 5 P500 # 6 P800 # 4 P1000 # 3 P1200 # 2 P1500 # 1 2500"...
[13:06:27] <tom3p>  they show the robot is a tiny 6dof using rc servo motors. and the controller is (i think) a serial ascii command to pwm channel thingy.
[13:06:34] <tom3p> he's not using any feedback right now, he's not using cartesian now.
[13:06:39] <tom3p> if he uses SIM to get the current joint positions, how would the joint posn's be transferred to the serial device? thru HAL?
[13:06:40] <tom3p> ( feedback is all visual, delay between motions is entirely up to operator, not repeatable, not cnc, just ideal math output translated to pwm channel)
[13:11:48] <tom3p> haha "exterminate!" http://arexx.com.cn/UploadFiles/20081120152918134.jpg
[13:12:52] <SWPadnos> heh - the Daleks have arrived
[13:16:42] <tom3p> and their 'lathe' looks suspiciously mill - like (stepper to band drives) http://www.arexx.com.cn/UploadFiles/2008226135012398.jpg
[13:27:17] <mhaberler> cradek - yes, a 5i20/hm2 stepper config
[13:27:27] <tom3p> the manual on the arm ( in chinese) shows that there's a simpler hand pendant with just jointNmore, jointNless buttons. http://www.arexx.com.cn/uploadfiles/RP6_RobotArm_manual.pdf
[13:28:49] <micges_work> tom3p: re mindThomas, positions could be transfered via userspace serial port hal driver
[13:31:27] <tom3p> micges_work: are there any serial drivers for hal ?
[13:31:47] <micges_work> tom3p: nope but it's easy to write
[13:32:09] <SWPadnos> the modbus drivers use serial
[13:33:15] <mhaberler> thanks - located pncconf, will give it a stab
[13:33:32] <SWPadnos> remember - it's a work in progress :)
[13:33:51] <SWPadnos> now here's a handy device: http://thermaltakeusa.com/Product.aspx?S=1268&ID=1895
[13:34:41] <tom3p> haha portable tiny hard drives... 'whats that in your pocket or...'
[13:34:51] <SWPadnos> just happy to see you
[13:35:28] <tom3p> hmm, 2 drive raid , hot swappable, yes, handy
[13:35:41] <SWPadnos> and the ability to copy from external drive to external drive
[13:35:50] <SWPadnos> and connect via esata, so it's faster
[13:39:13] <tom3p> micges_work: would the 'serport' driver ( it exists ) be a starting place?
[13:39:22] <SWPadnos> probably not
[13:39:39] <SWPadnos> that one doesn't actually move any data around, it only uses the control lines as I/O
[13:40:53] <SWPadnos> jepler had made a simple serial IO thing, but I don't know if the code still exists
[13:41:19] <Valen> how cheap could one make a gantry style mill do you think?
[13:41:21] <SWPadnos> I think it talked to an AVR based board, the serial protocol was named "DPP", for "Dumbest Possible Protocol"
[13:41:30] <Valen> excluding the electrics side of things
[13:41:50] <Valen> +-1mm or so would be fine
[13:41:51] <SWPadnos> $50 in wood and fasteners
[13:42:06] <Valen> The missus is thinking of doing some fancy doors
[13:42:07] <SWPadnos> get some nice thick oak
[13:42:24] <Valen> I was going to use 24mm (inch) MDF
[13:42:31] <Valen> sliding doors
[13:43:13] <Valen> got any URL's on anybody who has done "cheapest possible gantry mills"?
[13:43:25] <SWPadnos> not offhand
[13:44:09] <SWPadnos> you can get a lot done with pipe and drawer slides, but you'll definitely need to think about what you want to cut with it, and how fast
[13:44:35] <micges_work> tom3p: you need serial driver for sth?
[13:44:36] <Valen> MDF and a wet week is fine
[13:45:32] <tom3p> micges_work: i wondered how to do it, i now see it ends up with inb or outb to a file device. just wondering how.
[13:46:28] <micges_work> yes, if driver is in rt
[13:46:43] <micges_work> if it is in userspace it is few lines of python code
[13:46:56] <micges_work> very few
[13:48:01] <SWPadnos> especially for a write-only system
[13:48:15] <SWPadnos> (like sending positions to a controller)
[13:48:21] <SWPadnos> bbiab
[13:52:21] <tom3p> thx , i found some of the jepler arduino serial python code, uses python-serial ( only reads )
[13:54:09] <tom3p> nope, got write too arduino.analog-out-## and thats pwm, i think midThomas has hope.
[13:58:28] <BJT-Work> BJT-Work is now known as JT-Work
[14:05:41] <cradek> mhaberler: john k points out that interpolated position could be added to hm2. but if you have a mesa you can use a high resolution encoder and be done - do you have one?
[14:07:46] <SWPadnos> does irssi wrap long lines for you?
[14:09:11] <cradek> of course
[14:09:49] <cradek> http://timeguy.com/cradek-files/emc/irssi.png
[14:10:18] <mhaberler> last time I tried position-interpolated on the sw encoder it helped a lot
[14:10:19] <mhaberler> if there's no software fix I'll throw hardware at it and get me a higher res encoder - just read up on the #emc-devel discussion yesterday and begin to understand where this behaviour comes from -starts to make sense
[14:10:48] <jymm> SWPadnos: http://arduiniana.org/projects/the-reverse-geo-cache-puzzle/
[14:12:22] <mhaberler> looks we dont need quadrature dividers, but quadrature multipliers ;-)
[14:13:48] <SWPadnos> jymm, cool :)
[14:14:13] <jymm> SWPadnos: Yeah, I thought so.
[14:15:09] <tom3p> way cool
[14:16:33] <tom3p> i love the airport security conversation
[14:20:21] <Dave911_> Dave911_ is now known as Dave911
[15:38:15] <skunkworks_> Guest591: hello
[16:05:55] <alex_joni> this is interesting: http://www.austriamicrosystems.com/eng/Products/Magnetic-Encoders/Linear-Encoders
[16:08:58] <tom3p> do they sell the strips/rings?
[16:13:38] <alex_joni> http://www.siko.de/produkte/magline/magnetbaender/details/mb100/
[16:13:41] <alex_joni> tom3p: I don't think so..
[16:13:47] <alex_joni> but there are others that do
[16:15:30] <MrSunshine_> is that only the chips ?
[16:15:37] <_tarzan_> is a strip neeed for a Linear-Encoder to work?
[16:33:04] <tom3p> rats, old cassete tape isnt strong enuf field
[16:33:15] <tom3p> ;)
[16:36:30] <MarkusBec_away> MarkusBec_away is now known as MarkusBec
[18:11:56] <andypugh> Any ideas how to split a -1, 0, +1 signal into three individual bits in HAL?
[18:13:09] <micges> signal for what?
[18:13:29] <cradek> classicladder can easily manipulate s32 values like that (although this sounds like an odd hal signal - what is it?)
[18:14:20] <cradek> |--[%IW0 < 0]---(%Q0)---| etc etc
[18:15:01] <andypugh> It's the abs-hat0y-position joypad value. It comes into HAL as -1 for left, +1 for right and 0 for centre. I was intending using it to drive spindle on, spindle off, spindle faster, spindle slower
[18:15:07] <jepler> if it's a float, wcomp might be the right choice. It has "out" (between), "over" and "under" outputs. You'd set min -.5 and max .5 or something
[18:15:29] <cradek> is it s32 or float?
[18:16:01] <andypugh> wcomp looks about ideal. I hadn't read down the list as far as w
[18:17:02] <andypugh> I am not sure what it is, as the real CNC machine that I am VNC-ing to doesn't have it plugged in. Time to plug it in, I guess.
[18:17:26] <andypugh> Unfortunately it won't load the components without the hardware
[18:29:10] <andypugh> Actually, that might prove bothersome. Is there a way to ignore a HALFILE that fails? It might be annoying if EMC will only boot if it can find the Joysick device in the USB port.
[18:29:35] <cradek> nope
[18:29:49] <SWPadnos> I don't think you can do it from the emc run script, but halrun -k will "k"eep going even if it wncounters errors
[18:29:52] <SWPadnos> encounters
[18:29:57] <SWPadnos> err, halcmd -k
[18:30:05] <andypugh> So, no try-catch in HAL then?
[18:30:10] <SWPadnos> har har
[18:30:54] <andypugh> OK, So I might want two different .ini files then.
[19:39:13] <andypugh> Does anyone know what determines the step size of the spindle increase/decrease buttons?
[19:42:12] <micges> it's hardcoded
[19:42:24] <micges> (I think)
[19:43:14] <cradek> yep
[19:43:40] <andypugh> OK, no problem
[19:44:23] <andypugh> M4 Sxxx works when I care.
[20:25:15] <hugomatic> I have a python question... is the bwidget part of Tkinter or is it a TCL addon or a simple python lib? My program runs fine on my emc2 machine but fails on windows. thanks
[20:27:23] <cradek> I think bwidget is a separate package
[20:28:17] <hugomatic> thanks cradek... thats too bad, now I have to choose between convenience and portability
[20:28:44] <cradek> https://launchpad.net/ubuntu/+source/bwidget
[20:29:10] <tom3p> has anyone tried kexec-acpi-shutdown.sh ?
[21:03:34] <andypugh> is there a shortcut to adding multiple functions to a thread?
[21:04:10] <cradek> some components have a special "run all of them" function name
[21:04:35] <andypugh> I am thinking that loadrt mult2 count = 100 and then addf.0 servo-thread ... addf.100 servo-thread would be tedious
[21:04:55] <andypugh> Not that I plan on doing that
[21:05:43] <cradek> yeah I don't think mult2 has it
[21:05:51] <cradek> would take 100 hal commands to add them
[21:06:51] <andypugh> supplementary question, why does the joypad-pendant example used sum2 with a gain of -1 instead of mult2 with an in0 of -1?
[21:07:06] <andypugh> (To reverse an axis)
[21:07:32] <andypugh> does it save a floating point operation perhaps?
[21:24:59] <MattyMatt_> always worthwhile in a program that is destined to run on ARM one day
[21:25:33] <MattyMatt_> posh ARM have fpu these days, but I'm thinking NDS territory
[21:27:01] <MattyMatt_> but on x86 mult is just as quick as add these days
[21:30:06] <andypugh> Thing is, 'tis all FP anyway, so seems daft
[21:30:42] <andypugh> sum2 is in0 * gain0 + in1 * gain1 + offset
[21:30:55] <andypugh> mult2 is in0 * in1
[21:31:16] <andypugh> If the aim is to negate a number, then the latter seems more logical.
[21:31:33] <andypugh> (And subtracting from zero probably even more so)
[21:31:54] <micges> andypugh: maybe that is leftover from some magic
[21:32:01] <andypugh> Though I am not sure if FP subtraction is quicker than multiolication
[21:33:03] <andypugh> Indeed, perhaps he was using gain at some point.
[21:33:16] <MattyMatt_> the idea these days is to write what appears logical, and let the compiler worry about the code
[21:33:41] <andypugh> This is in HAL
[21:33:45] <andypugh> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Simple_Remote_Pendant
[21:33:54] <MattyMatt_> if gain is hard coded to -1, maybe that makes some sense
[21:34:14] <andypugh> No, needs a setp instruction, which works equally well for mult2
[21:36:25] <andypugh> Does anyone know of a USB gamepad with decent analog range? My cheapy sticks at 127 counts for about the first 20 degrees of left movement, then goes to 0 in the next 10, then does nothing for the next 15.
[21:36:59] <andypugh> No amount of meddling with gain curves is going to help that. The right-travel is better, but still hits full scale with lots of travel left.
[21:37:21] <MattyMatt_> andypugh, that could be a deliberate "dead zone" inserted by the driver
[21:37:35] <andypugh> No, this is raw counts.
[21:37:49] <andypugh> And it is not symmetrical, at all.
[21:38:32] <andypugh> Going right the counts drop as soon as the stick moves.
[21:38:51] <MattyMatt_> you can make a table to make it linear
[21:39:08] <andypugh> I am assuming that the broken driver CD it came with was for software config, not firmware cal
[21:39:27] <MattyMatt_> it's not firmware usually
[21:39:48] <andypugh> I can't linearise if the raw counts don't change.
[21:40:19] <MattyMatt_> the logitech on that wiki page is good. I have one, but cheapo PSX ones in a SuperJoy adaptor are just as good
[21:40:59] <andypugh> Yeah, I am looking at the rumblepads if they have a better analogue performance, but reviews on that aspect are mixed.
[21:41:31] <andypugh> (Though I wonder if the bad reviewer had forgotten to press the "mode" button, as I did?
[21:41:49] <MattyMatt_> I get a good sweep, and any dead zone is only one inserted to stop jitter
[21:42:03] <andypugh> <thinks: is the mode button status programmable>
[21:42:17] <andypugh> Sold then.
[21:42:23] <andypugh> Cordless or wired?
[21:42:28] <MattyMatt_> wired
[21:43:04] <andypugh> Hmm, I wonder if I can make new buttons with meaningful logos on them :-)
[21:44:02] <MattyMatt_> probably easier to make a whole pendant with big square buttons
[21:44:43] <andypugh> Not USB it isn't.
[21:44:45] <MattyMatt_> Wiimote is wireless & one-handed
[21:45:24] <MattyMatt_> USB isn't that scary. you can do it with a PIC
[21:45:48] <andypugh> No, _you_ can do it with a PIC.
[21:47:00] <MattyMatt_> make the pendant big enough to fit the logitech pcb
[21:47:24] <andypugh> Now that would work, good thinking.
[21:48:33] <MattyMatt_> I wish NDS had usb, both kinds
[21:49:15] <andypugh> <baffled look>
[21:49:25] <MattyMatt_> there's a new Samsung touchscreen phone that's almost as cheap as a DS
[21:50:07] <MattyMatt_> nds = nintendo. bothkinds = host + device (A+B)
[21:50:36] <andypugh> Ooh! that reminds me, I nearly paid £55 for an Apple mouse today. The new one is cordless and has no buttons. The whole top is touch-sensitive and responds to gestures in an iphone-like way
[21:50:38] <MattyMatt_> usb2go does both kinds, and p2p through the 5 pin mini usb
[21:51:21] <cradek> a touch sensitive mouse sounds awful - you can't rest your hand on it?
[21:51:44] <andypugh> As I am sick of dismantling my Mighty Mouse scroll-ball to remove fluff to persuade it to work again....
[21:52:01] <MattyMatt_> I got coffee in my mouse button yesterday, and it's still cruchy, so I could be sold on no buttons right now
[21:52:30] <andypugh> No, it just uses the touch-sensitive-ness to work out what button you pressed, it still has a whole-body click
[21:53:34] <andypugh> The current mouse is the same, no physical buttons, the whole top moves, and it looks at where you presses to work out what you meant. The new one lets you swipe up-down-left-right to scroll too
[21:53:45] <MattyMatt_> I need to get my ball mouse out again. I got a pixelling job and balls are still best for that
[21:54:13] <MattyMatt_> gotta grow my thumbnail
[21:54:29] <andypugh> I think you will find they have all been cannibalised by cnc-geeks
[21:54:58] <andypugh> OK, elaborate on the thumbnail thing?
[21:55:17] <MattyMatt_> I never thought of that. these serial mice are now rare and precious. good job I got a few
[21:55:57] <MattyMatt_> ball mice work great for 1/2 hour, then you need to scrape the rollers with a hard flexible tool
[21:56:02] <andypugh> I used to do graphics pixel-by pixel by writing lines of basic code. It never occurred to me to write a drawing package :-)
[21:56:15] <andypugh> 'Course we had fewer pixels back then
[21:56:26] <MattyMatt_> i typed them in in hex :)
[21:56:55] <MattyMatt_> that was posh. graph paper and a sector editor
[21:56:56] <andypugh> Yeah, makes sense for sprites, I was doing loading screens
[21:57:28] <MattyMatt_> I typed the loading/title screen for MM in hex
[21:58:51] <MattyMatt_> but for the animated sprites, I did write a special editor with a key for each frame
[21:59:30] <MattyMatt_> a technique that only works for 4 frames, because you only have 4 fingers on your left hand
[22:00:16] <andypugh> The MM loading screen inspired me to consider making a number plate out of black and yellow scotchlite and black and yellow gloss that would show a different number under flash photography
[22:00:41] <MattyMatt_> :)
[22:02:39] <MattyMatt_> xbox controller would be better for conversion, as the buttons always wear out first
[22:03:01] <MattyMatt_> so one with dodgy buttons but good sticks is easy to obtain
[22:03:15] <MattyMatt_> and it has 2 more analog inputs
[22:04:11] <andypugh> I just remembered that worldofspectrum gives me a credit for a game I didn't write, because I signed the loading screen :-)
[22:04:21] <andypugh> ftp://ftp.worldofspectrum.org/pub/sinclair/screens/load/r/gif/Redcoats.gif
[22:04:32] <MattyMatt_> that's a credit
[22:04:57] <MattyMatt_> the last commercial thing I did has 66 names on it, including somebody's dog
[22:04:58] <andypugh> http://www.worldofspectrum.org/infoseekpub.cgi?regexp=^Andy+Pugh$
[22:05:59] <andypugh> Yeah, we were different ends of the market. I played your games to death, I doubt you ever saw mine.
[22:07:29] <MattyMatt_> and I'm not seeing them now :( mouse button seized up entirely
[22:07:44] <MattyMatt_> right, time to break out ye olde ballmouse
[22:08:38] <andypugh> Sounds like the time to splash out on the new Apple one and tell me how it works in practice.
[22:11:13] <alex_joni> heh
[22:16:05] <MattyMatt_> time to splash out some soapy water in my main mouse. I don't have a mouse mat
[22:16:20] <MattyMatt_> I'd forgotton about them
[22:17:00] <andypugh> How quaint
[22:17:30] <andypugh> I bought a nice gloss-white computer desk from Ikea, that didn't work at all with an optical mouse...
[22:18:07] <MattyMatt_> maybe if I spent more than £4 on my optical mice they'd be good enough for pixelling too
[22:18:23] <SWPadnos> tape a piece of paper to the desk
[22:18:44] <MattyMatt_> brown paper
[22:18:53] <SWPadnos> white works great too
[22:19:26] <MattyMatt_> I find it doesn't. wood/denim/couch arm great tho
[22:19:45] <MattyMatt_> I do use £4 mice tho :)
[22:19:50] <SWPadnos> I guess I buy $20 mice instead of $10 ones
[22:20:10] <andypugh> This new $75 Apple mouse apparently uses laser-tracking...
[22:20:28] <SWPadnos> there are plenty of $30 laser mice around
[22:20:32] <andypugh> http://www.apple.com/magicmouse/
[22:22:16] <MattyMatt_> the buttons in this one look like proper little microswitches
[22:23:27] <MattyMatt_> not really fit for heavy use tho, but they'd do for an 8"x8" plastic mahine
[22:25:09] <MarkusBec> MarkusBec is now known as MarkusBec_away
[22:27:06] <andypugh> You still looking to build a machine Matt?
[22:29:37] <MattyMatt_> construction is under way
[22:30:28] <MattyMatt_> I've got a solid drilling machine now for putting the bold holes in the ends of my timbers
[22:30:39] <MattyMatt_> ^bolt holes
[22:31:39] <MattyMatt_> with cross-dowels, so it's all adjustable at the end
[22:33:19] <MattyMatt_> 2 pairs of shelf sliders. one pair as they would be in a shelf, and the other pair opposing them and at right angles to provide lateral stiffness
[22:33:23] <andypugh> OK, because Frallor (or whatever he is called) was trying to move his aluminium and steel one on to a new home. I think that money was likely to be involved too, though.
[22:34:20] <MattyMatt_> AchiestDragon offered me his, but very day I'd spent on frame-making tools
[22:35:08] <MattyMatt_> I'm done spending on the frame. all new money is on motors & controller
[22:36:50] <MattyMatt_> And I cant see a way to make a decent Z axis without some metalworking tools
[22:39:57] <MattyMatt_> I see now why all machines have the motors on the outside. for speedy cannabalism :)
[22:42:23] <MattyMatt_> the printer trade could have gone that way. "How fast is it?", "How fast do you want it to be, Sir?"
[22:47:59] <andypugh> I saw a really interesting printer at Systime Computers a long time ago. It had a hammer for every character position, and a continuous loop of characters spinning at high speed undereath. When the right character was under the right hammer, bang. It was optimised with more than one of the common characters, and could fire all the hammers as the same time if necessary.
[22:48:34] <MattyMatt_> that's a classic line printer, as in LPT1:
[22:49:31] <andypugh> Yes, though technically a band printer in this case
[22:49:44] <andypugh> (Guess who is reading the wiki page?)
[22:50:52] <MattyMatt_> I'm wondering if the solenoids off a print head are any use. tiny chisels?
[22:52:13] <andypugh> Which reminds me of something else I have been idly pondering. You are looking to make woodcarvings I believe? I wonder if anyone has tried doing that with a Puma robot, an air chisel and actual chisel bits?
[22:52:25] <skunkworks> andypugh: we had a few of those - the paper flew out of them
[22:52:44] <andypugh> You would get a much more authentic finish than routing.
[22:52:59] <andypugh> Aye, the speed was what impressed me.
[22:53:03] <MattyMatt_> and you good do walls with a puma
[22:53:12] <MattyMatt_> could
[22:53:22] <MattyMatt_> and block of marble
[22:53:44] <andypugh> However, I suspect that you would need to have a vision system to see when the grain was running in.
[22:54:45] <MattyMatt_> your G code would probably ignore that, or make assumptions based on regular grain direction
[22:54:56] <MattyMatt_> so keep the chisel sharp
[22:55:20] <andypugh> http://en.wikipedia.org/wiki/Lp0_on_fire
[22:55:38] <MattyMatt_> it would be better guided than a hand-held chisel probably
[22:55:56] <andypugh> More to it than sharp chisels, in my limited experience. But I have only ever tried carving oak.
[22:56:18] <MattyMatt_> oak I will rout :)
[22:57:23] <john_f_> Hi I am getting closer to being done with my retrofit. I have a relay contact that indicates that the spindle is running. I was wondering how to hook that up so that the program will pause until the spindle running input goes "True".
[22:57:53] <SWPadnos> john_f_, there's an "at-speed" input to the motion controller
[22:57:59] <MattyMatt_> or get one of those angled saw heads for dremels, and put a rotating axis on (I want this for glasscutting anyway)
[22:58:18] <SWPadnos> you can feed it with whatever you want
[22:58:45] <john_f_> OK I wasn't sure if that was a good use for that inptu. I will do it.
[22:58:55] <john_f_> Thanks
[22:59:03] <SWPadnos> you may want to AND it with an actual check for the spindle being close to the correct speed :)
[22:59:17] <SWPadnos> the wcomp (window comparator) component can be useful there
[22:59:22] <john_f_> don't have an encoder on the spindle yet
[22:59:32] <SWPadnos> is there an output from the VFD?
[22:59:38] <SWPadnos> or modbus?
[23:00:21] <SWPadnos> you can also use a time delay in HAL - just wait 5 seconds or something after the "spindle on" input goes true
[23:00:34] <john_f_> Will do that in the future when I get a VFD right now it is just the BP variable speed head
[23:01:23] <MattyMatt_> I suppose for a steerable saw, it would be better to make it belt driven and have the motor rotate with the blade, rather than use a crown gear
[23:02:01] <MattyMatt_> does "rotate about Z axis" have a usual name?
[23:02:09] <SWPadnos> C
[23:02:10] <toastydeath> rotation around Z is usually the C axis
[23:02:34] <andypugh> MattyMatt: Sounds more rugged
[23:03:06] <MattyMatt_> yeah the spindle would be supported both sides
[23:03:17] <SWPadnos> bbl
[23:04:47] <MattyMatt_> for the more modestly size machine, piezo chisels can carve stone
[23:06:36] <MattyMatt_> ultrasonic
[23:07:09] <MattyMatt_> not very predictable tho, apparently. it's good for breaking up boulders
[23:07:15] <andypugh> Actually, I wouldn't have a bearing each side, as that means you can't cut hard against a shoulder
[23:07:55] <andypugh> Probably bearings each side of the belt, but have the blade dished and cantilevered.
[23:08:30] <MattyMatt_> ah lasers are getting cheaper every year :)
[23:08:59] <andypugh> http://toolmonger.com/2007/07/16/chainsaw-carve-with-your-angle-grinder/
[23:13:53] <MattyMatt_> nice, but I don't have ready access to freshly felled trees
[23:14:43] <MattyMatt_> except in the park. there's 90 yo oaks just ready to harvest
[23:14:56] <andypugh> I am sure that it would carve less recently felled trees. We found a chainsaw quite handy for mortice and tenon joints rebuilding my dad's house.
[23:15:01] <MattyMatt_> by rights they should, and plant fresh ones before these ones rot
[23:18:23] <andypugh> 90 years is reasonably young for an Oak though.
[23:19:49] <MattyMatt_> these ones all give the impression they'll be hollow in 20 years, or they'll need props under the branches
[23:21:20] <MattyMatt_> the straight ones look like fine timber tho, the kind everyone moans they can't get when they've got a simple cathedral roof to renovate
[23:22:23] <MattyMatt_> I can suggest this on IRC :) I wouldn't dream of saying it locally. I'd get lynched
[23:22:36] <andypugh> We found our wood locally, in fact my dad remembered the trees as saplings when he was little.
[23:23:41] <andypugh> All felled and sawn on site by a portable sawmill. This is the actual wood being cut. http://www.bodgesoc.org/wood2.jpg
[23:25:15] <MattyMatt_> I call my table saw a sawmill. 14" blade
[23:25:51] <MattyMatt_> so far I've only used half of it (for thicknessing)
[23:26:04] <tomp> tomp is now known as tom3p
[23:30:57] <MattyMatt_> it has opened the possibility of squariing telephone poles. they are the cheapest massive timbers I can get readily
[23:32:02] <tom3p> woohoo, Alexey Starikovskiy wrote: ... a K45... with 2 to 8 uS latency thats a 99$ barebones box ( u add cpu, mem,hd ). i tested before and it was crap.
[23:32:11] <tom3p> i gotta find out how he got 2 to 8 microsecs latency! i was just packing it off to a niece and spent a day loading it with cutsey apps. ( she gets the ugly tower now ;)
[23:32:24] <tom3p> i was just packing it off to a niece and spent a day loading it with cutsey apps. ( she gets the ugly tower now ;)
[23:33:41] <tom3p> uh arent telephone poles stinky? creosote preservative?
[23:34:05] <MattyMatt_> I'm not sure why even a RT kernel is used for emc. A dos program could poll in better than 2 to 8 us
[23:34:15] <MattyMatt_> mm stinky
[23:35:28] <andypugh> Are you confusing speed with accuracy?
[23:35:45] <tom3p> just what he wrote in the mail list
[23:36:02] <andypugh> I was asking MattyMatt
[23:36:33] <MattyMatt_> the whole polling loop could poll more often than that
[23:37:32] <andypugh> Yeah, but the thing about the RT stuff is that your thread absolutely will be polled every cycle, nothing else can interfere.
[23:38:01] <andypugh> You can have really slow systems that are real-time.
[23:38:01] <MattyMatt_> e.g. on a 266Mhz bus, you could do 266 memory ops in the loop and still poll every us
[23:38:42] <andypugh> Spectrum was real-time, or the screen display wouldn't have worked :-)
[23:39:34] <MattyMatt_> more so the zx80
[23:40:31] <andypugh> No, that was a good example of not real time. Every time you pressed a key it suspended the real-time thread and blanked the screen
[23:41:27] <MattyMatt_> so the answer to RTOS is not a fancy kernel, but to devote a cpu to every parameter
[23:41:42] <MattyMatt_> or at least one per axis
[23:42:05] <MattyMatt_> broadcast a sync signal perhaps
[23:43:06] <andypugh> To an extent, yes. That is what the FPGA boards do, but you still ideally want to guarantee that they will be serviced regularly, if not necessarily frequently.
[23:44:47] <andypugh> The thing is that if you are running a 25uS base thread everything in that thread is guaranteed to be polled every 25uS. The OS isn't going to wander off and check for MSN updates or whatever and forget to run the thread.
[23:46:19] <andypugh> I had a really quite effective cam and crank signal emulator out of the parallel port of my laptop running a 100kHz loop in an excel macro of all things (Matlab managed 6Hz). It was fine except every few seconds Windows would steal the CPU and break the pulse train.
[23:51:02] <MattyMatt_> i need a CF to IDE adaptor before I install emc ubuntu
[23:51:32] <MattyMatt_> I'm down to one working pata drive, and I decided not to buy any more
[23:51:48] <MattyMatt_> better to spend the money on mobos with sata
[23:52:06] <andypugh> I have never had a hard drive failure.
[23:52:21] <MattyMatt_> I had 3 in one night :p
[23:52:35] <andypugh> Not even when I was using a 6 year old computer.
[23:52:52] <jymm> andypugh: Feel VERY VERY VERY lucky.
[23:53:00] <andypugh> I only own 2, to three in a night would be tricky.
[23:53:20] <andypugh> One in the EMC machine, one in this iMac
[23:53:55] <MattyMatt_> this was/is a crappy asus mobo. it has done it before. that drive only works for 10 minutes after an hour in the freezer now
[23:54:49] <andypugh> I think I have only owned 6 hard drives in my life. There goes my geek-cred.
[23:54:55] <MattyMatt_> when the mobo hits 80C it's supposed to shut down, but what it does is somehow screw any drives in the machine
[23:56:29] <MattyMatt_> I so want to scrap that mobo, asap
[23:56:49] <andypugh> Mine it for parts, with a blow-torch :-)
[23:56:57] <MattyMatt_> and that will free my one remaining good pata drive for cnc, but I'd rather have CF
[23:57:31] <andypugh> Yeah, you don't need much storage space on the CNC machine, so solid state sounds sensible.
[23:57:51] <andypugh> Assuming that is what you mean.
[23:57:51] <MattyMatt_> there's better parts on a 486 board
[23:58:02] <MattyMatt_> yeah that's what I mean
[23:58:15] <MattyMatt_> 16GB of CF is cheap and reliable
[23:58:45] <MattyMatt_> and better for real time stuff, as you don't have Smart Drive delays