#emc-devel | Logs for 2007-06-07

[00:37:35] <cradek> jmk having to redraw my cheat sheet stuff makes me think I should find a cad program from the truetype-and-laser-printer age instead of the pen plotter age
[00:38:23] <cradek> but that would probably mean windows, unless I'm very lucky with wine
[00:39:22] <skunkworks> your doing this in autocad 12 arn't you
[00:39:31] <cradek> yeah
[00:39:37] <cradek> it's all I have
[00:39:49] <skunkworks> :) that is probably what I would do also
[00:40:11] <cradek> I'd have to give up my autocad knowledge - I'm pretty good with it
[00:40:26] <cradek> but I also don't want to jump to something that requires me to find a windows license
[00:41:01] <skunkworks> Doing acad for 5+ years running a laser cutter make it very easy to use.
[00:41:12] <skunkworks> maks
[00:41:13] <skunkworks> makes
[00:43:02] <skunkworks> so the telescope tracking mount didn't work out of the box. I ended up having to take it appart and fix the encoder on one of the axis
[00:43:13] <cradek> working now?
[00:43:49] <skunkworks> seems to - cloudy here to actually try it. but now it doesn't go around in circles until it errors
[00:43:56] <cradek> ha
[00:44:01] <cradek> sounds like a good sign
[00:45:19] <skunkworks> it has like a mouse encoder on each axis.
[00:46:16] <skunkworks> It will do the 2 star alignment just fine so I think it should work.
[00:48:13] <cradek> does the software know about earthly things like those iridium(?) satellites?
[00:48:38] <skunkworks> yes - it does
[00:49:03] <skunkworks> it has like 30,000 objects including asteroids and such
[00:49:51] <cradek> that sounds really fun
[00:49:55] <cradek> it tracks too I suppose?
[00:50:02] <cradek> maybe you could do photography with it
[00:50:21] <skunkworks> the scope has a camera mount
[00:50:25] <cradek> nice
[00:50:45] <skunkworks> or a place to mount a camera with an adaptor.
[00:50:51] <skunkworks> Yes it tracks
[00:51:22] <skunkworks> pretty small scope though - but it will be neat.
[00:52:26] <skunkworks> this is it http://www.weasner.com/etx/observations/2005/dsx90-2.html
[00:53:17] <cradek> cool
[00:53:23] <cradek> is it dark where you are now?
[00:53:32] <skunkworks> no - not yet
[00:53:38] <cradek> um I mean, since your move, does it get dark at your house?
[00:53:41] <skunkworks> ;)
[00:53:48] <cradek> or do you have to go for a road trip every time
[00:54:29] <skunkworks> The astronomy club uses a flying field
[00:54:37] <skunkworks> on a bluff
[00:55:11] <skunkworks> I am in town so viewing isn't the greatest - my parents house is about 20 minutes away and much darker
[01:08:06] <jepler> a telescope is one of those things I think I want sometimes, but I know in my heart I'd use it too rarely to justify it
[01:08:34] <jepler> amazingly, that's kept me from buying one
[01:19:19] <skunkworks> This was only 'too good to pass up deal'
[01:21:09] <skunkworks> $90 from sams club... because it was broken. Call meade and had me send in the broken part back for replacement.
[01:23:49] <jepler> I see
[01:23:53] <jepler> haha sams club
[02:03:20] <jepler> I tried the "control program progress with jog wheel" on a real machine (nist lathe)
[02:03:46] <jepler> it is a bit jittery when you turn the jog wheel one detent at a time
[02:03:59] <jepler> when you give it a whirl and get ahead of the program it is nice and smooth
[02:04:34] <jepler> I bet people who like to turn on DTG, turn feed override way down, and watch whether the tool will hit the chuck would also like this gizmo
[02:17:25] <jmkasunich_> jmkasunich_ is now known as jmkasunich
[02:17:50] <jmkasunich> hi guys
[02:30:43] <skunkworks> jepler: can you go backwards?
[02:31:18] <jepler> skunkworks: no
[02:31:34] <jepler> skunkworks: it's just a hack that plays with the "feedhold" HAL pin
[02:31:39] <jepler> e.g., 1 click = feedhold set to TRUE for .01 second
[02:31:45] <skunkworks> sorry - I had to ask :)
[02:31:59] <skunkworks> neat
[02:32:53] <jepler> oh by the way this was with my AVR USB jogwheel
[02:33:18] <skunkworks> very neat
[02:54:40] <jepler> jogging with it was a little bit uneven but not terrible if the alternative is no jog wheel at all
[02:56:32] <cradek> anyone planning to bring a 'scope?
[02:57:58] <jepler> not me
[02:58:16] <jepler> I figure if one of us was to bring a scope, it should be you
[02:58:29] <cradek> jepler: I think we need to get you a 'vista cruiser'
[02:58:50] <cradek> (I think that's the huge 70s station wagon)
[02:59:32] <jmkasunich> cradek: I'll be bringing a scope
[02:59:39] <cradek> ok I'll leave mine then
[02:59:47] <jmkasunich> (and a current probe, and frequency counter, and a few other handy bits)
[03:00:10] <jmkasunich> yeah, save room in the car for the crap I'm unloading on you
[03:05:22] <SWPadnos> I'll bring a scope or two as well
[03:07:23] <jmkasunich> SWPadnos: did you see the cool 5 axis mill cradek found at HGR?
[03:07:37] <SWPadnos> was it blue?
[03:08:01] <jmkasunich> don't remember the color
[03:08:10] <jmkasunich> it was not-huge, and an interesting layout
[03:08:15] <SWPadnos> I think it did see it, if ti's the blue one :)
[03:08:28] <SWPadnos> I didn't see all that much detail in the photo
[03:08:40] <jmkasunich> http://www.hgrindustrialsurplus.com/search-products/product-detail.aspx?id=20-760-068
[03:08:49] <jmkasunich> dark blue/gray I guess
[03:08:57] <jmkasunich> the color isn't what stands out
[03:09:01] <jmkasunich> unfortunately the price does
[03:09:07] <SWPadnos> ok. that's a different one, but I did see this one as well
[03:09:12] <SWPadnos> heh
[03:10:01] <SWPadnos> interesting. kind of like a lathe/horizontal mill setup
[03:10:19] <jmkasunich> bottom of this page: http://www.barer.com/proteo5.html shows the axis setup
[03:10:26] <SWPadnos> yep - I
[03:10:30] <SWPadnos> yep - I'm there now
[03:11:04] <SWPadnos> I'm not understanding what the V axis is
[03:11:10] <SWPadnos> it looks parallel to W to me
[03:11:23] <jmkasunich> V rotates around X
[03:11:32] <SWPadnos> ah, W is on the V platform
[03:11:33] <jmkasunich> w rotates around Z or Y, or anything in between
[03:11:35] <jmkasunich> yeah
[03:11:44] <SWPadnos> now I see it. the perspective was screwed up for me
[03:14:14] <cradek> (fwiw, new linux-image-2.6.17-rtai3.5 deb in /experimental)
[03:14:23] <cradek> fixes the keyboard problem, nothing else
[03:14:38] <jmkasunich> thats the SMP? or 64-bit?
[03:14:41] <cradek> yes smp
[03:14:57] <SWPadnos> what is the keyboard problem? I've seen some discussion of it, but don't know what it is.
[03:15:09] <cradek> sometimes while typing you get 400 of a character instead of 1
[03:15:15] <cradek> other times, a keypress is lost
[03:15:32] <jmkasunich> I've had that happen a few time when running dapper in a vm under xp
[03:15:37] <SWPadnos> ah. that would be a problem
[03:15:49] <cradek> it was/is(?) a kernel bug
[03:15:59] <jmkasunich> it just keeps repeating indefinitely, until I hit the same key again - like a key release event was missed
[03:16:05] <cradek> yep that's the one
[03:16:06] <jmkasunich> I assume my case was a VM thing
[03:16:24] <cradek> I don't exactly know what kernels it's in
[03:16:43] <jmkasunich> I'm running stock dapper on that VM
[03:16:46] <cradek> ubuntu patched theirs a year ago, I took that patch
[03:16:51] <cradek> hmm
[03:16:58] <cradek> like I said, I don't know all the details
[03:17:23] <jmkasunich> it could be a vmware thing - many possible causes for lost release events, all resulting in the same symptom
[03:17:43] <SWPadnos> not a missing press
[03:17:50] <SWPadnos> though that's still a missed keycode
[03:18:04] <jmkasunich> well, missing press isn't as obvious
[03:18:26] <jmkasunich> if it happens once every several thousand keystrokes, you'll just assume you missed the key or didn't hit it hard enough
[03:18:34] <jmkasunich> missed release is a bit more noticable
[03:21:22] <cradek> SWPadnos: Daniels (effectively) says a proper fusee curve cannot be calculated, and your job as a watchmaker is to make a correctable compromise and then test it and tweak until it's good
[03:21:41] <SWPadnos> heh
[03:21:43] <jmkasunich> cradek: I saw that discussion, interesting
[03:21:46] <cradek> I'm not sure I'm satisfied by that, but it's what you'd end up doing anyway
[03:21:59] <jmkasunich> how critical is "good"?
[03:22:12] <SWPadnos> actaully, it's possible to make the drum have a variable winding pitch
[03:22:15] <cradek> depends on your goal as a watchmaker
[03:22:30] <SWPadnos> so the first example can be done with a custom drum and fusee
[03:22:39] <jmkasunich> semi-constant force on the geartrain is better than wildly varying, and wildly varying is what most mainstream watches have/had isn't it?
[03:22:40] <cradek> these were originally used on fricitional rest escapements like verge, and the equal force was the only thing to give you timekeeping
[03:22:49] <jmkasunich> oh
[03:22:56] <cradek> with modern detached escapements like the lever, it's much less critical
[03:23:18] <jmkasunich> I was assuming escapment technology that was at least as advanced as the fusee
[03:23:19] <cradek> but if your goal is to make a chronometer that varies < 1 sec a day, you may still want a good fusee
[03:23:49] <jmkasunich> good being what? a few percent variation in force over the winding range? fraction of a percent? 0.001%?
[03:24:05] <cradek> a few percent I imagine
[03:24:44] <cradek> as late as WWII hamilton (american company!) made ship's chronometers with fusee and detent escapement - the english style
[03:25:54] <cradek> <- timekeeping geek, sorry
[03:26:03] <jmkasunich> thats ok, its quite interesting
[03:26:18] <jmkasunich> if the book that archivist posted the pics of was online, I'd read it
[03:26:32] <jmkasunich> wouldn't buy it, bet its hard to find and expensive
[03:26:36] <cradek> me too - I don't have it
[03:27:00] <cradek> I have the Daniels book "Watchmaking" which is excellent but more on the practical side
[03:28:15] <cradek> ... on abebooks.com for $60+
[03:28:39] <jmkasunich> the archivist one, or Watchmaking?
[03:29:42] <cradek> Watchmaking
[03:29:58] <cradek> the Rawlings book is only $35+
[03:30:20] <cradek> more for a copy already in the US though
[03:30:34] <cradek> (abebooks is really great)
[03:31:41] <cradek> would be $50+ to get one here
[03:32:32] <jmkasunich> not bad if you have a serious interest, kinda steep for reading cause its neat
[03:32:39] <cradek> yep
[03:32:58] <cradek> I've paid more for old books, but only when I really want them
[03:33:33] <cradek> sometimes you can get stuff like this through ILL, good to try first
[03:35:52] <jmkasunich> I got the Moore "Foundations of Mechanical Accuracy" book that way
[03:36:02] <jmkasunich> interesting, but not really a keeper
[03:37:42] <cradek> I finally figured out that full thread depth (pointy tool) for UNC screws is always .866 * pitch
[03:37:57] <cradek> I don't know why I didn't see that long ago
[03:42:33] <jmkasunich> in the immortal words of Barbie: "math is hard"
[03:42:49] <cradek> ha I remember that uproar
[03:43:16] <cradek> how quaint what people used to worry about
[03:43:18] <jmkasunich> I hoped you did ;-)
[03:43:32] <jmkasunich> used to?
[03:43:43] <jmkasunich> people still worry about or get offended by stupid things
[03:43:47] <cradek> did you see bloomberg's comments about terror plots?
[03:43:54] <jmkasunich> no
[03:43:57] <cradek> they included "get a life"
[03:44:25] <cradek> don't obsessively worry about stuff that's unlikely to harm you, get a life
[03:44:33] <jmkasunich> yeah
[03:44:49] <cradek> he'll never run for president of 9/11, errrr, the US
[03:45:24] <cradek> http://www.theonion.com/content/news/giuliani_to_run_for_president_of_9
[03:45:46] <jmkasunich> lets not talk about politics
[03:45:59] <cradek> sorry
[03:46:17] <cradek> I thought it wasn't politics if it's funny, but maybe it's not universally funny
[03:46:35] <jmkasunich> didn't look at it yet
[03:46:46] <cradek> hey I got autocad to use postscript fonts, so I can have nice output now too
[03:46:54] <jmkasunich> cool
[03:47:00] <cradek> well it always knew how, but I didn't
[03:47:35] <cradek> http://timeguy.com/cradek-files/emc/arcs5.eps
[03:48:07] <cradek> your pictures are better anyway, but this is good to know about
[03:48:52] <jmkasunich> pretty
[03:49:01] <cradek> yeah 10x better than before
[03:49:43] <cradek> it still shows outlines on the screen, but when I generate postscript it uses the actual postscript font/text mechanism
[11:48:44] <jepler> I built a new smp rtai kernel (but it should have the same options as the last one)
[11:49:05] <jepler> at boot, and after running the "latency" test it doesn't have the lost interrupts problem I saw last time
[11:49:07] <jepler> I haven't run emc yet
[11:50:37] <jepler> ... emc locked it up
[11:50:46] <jepler> grumble
[11:56:45] <jepler> actually it's not quite dead, I was able to get all this incomprehensible information: http://pastebin.ca/547450
[12:10:06] <cradek> is that the amd64?
[12:11:18] <jepler> yes
[12:11:28] <jepler> that's why all the numbers are big and you've never heard of some of those registers
[12:11:48] <jepler> restarted, and tried disabling the code to run on the last CPU -- it's fine
[12:11:55] <jepler> added the code to run on the last CPU to the rtai latency test -- it's fine
[12:12:06] <jepler> reenabled the code in emc2 -- it's fine
[12:12:09] <cradek> haha
[12:12:55] <cradek> what a pain
[12:13:00] <jepler> indeed
[12:17:34] <jepler> and I should go to work
[12:36:57] <jepler> hi skunkworks_
[12:48:21] <skunkworks_> Hi Jepler
[12:55:07] <skunkworks_> How long is your drive to the workshop?
[12:55:41] <jepler> let me see what google says
[12:56:05] <jepler> google says "409 mi (about 6 hours 11 mins)"
[12:56:56] <jepler> seems like it took longer than that..
[13:01:16] <jepler> maybe that's about right when you exclude the time stopped for a meal in des moines
[13:01:26] <skunkworks_> says 5hr40min for me.
[13:01:36] <SWPadnos> and stopping for gas, waiting for traffic, tolls ...
[13:01:42] <skunkworks_> be we don't go that direction it shows.
[13:01:50] <skunkworks_> seems it took around 5hours
[13:03:36] <jepler> do you drive the speed limit? :-P
[13:03:48] <SWPadnos> it's a lower bound ;)
[13:04:30] <skunkworks_> dad drives - so normally exactly the speed limit
[13:04:36] <skunkworks_> :)
[13:04:51] <SWPadnos> hmmm. google says "1,109 mi (about 18 hours 3 mins)" for me
[13:05:03] <SWPadnos> but for some reason, I think it's longer
[13:14:08] <skunkworks_> jeeze - I typed in gainsville instead of galeburg duh
[13:14:21] <skunkworks_> yahoo says 4hr 40min
[13:14:43] <skunkworks_> http://maps.yahoo.com/;_ylc=X3oDMTExNmIycG51BF9TAzI3MTYxNDkEc2VjA2ZwLWJ1dHRvbgRzbGsDbGluaw--#mvt=m&q2=galesburg%20Il&q1=54661&trf=0&lon=-90.906372&lat=42.508553&mag=11
[13:19:40] <cradek> what are these "tolls"?
[13:19:45] <cradek> for that matter, what is "traffic"?
[13:20:31] <cradek> you new-englanders and your funny talk!
[13:22:30] <skunkworks_> if we went thru chicago - we would have tolls.
[13:22:43] <skunkworks_> and traffic ;)
[13:27:58] <skunkworks_> cradek: jepler: do you guys carpool?
[13:49:22] <jepler> skunkworks_: only at lunchtime
[13:49:36] <jepler> cradek lives out in the suburbs; I live downtown
[13:49:40] <cradek> we come to work from opposite directions unfortunately
[13:55:13] <skunkworks_> I ment for the workshop
[13:55:20] <skunkworks_> :)
[13:55:21] <cradek> oh of course
[13:55:33] <jepler> unless we have so much stuff it doesn't fit in one car :-P
[13:55:47] <skunkworks_> bringing cradeks truck?
[13:56:39] <cradek> no, we can't afford the $2000 it would cost for gas
[13:56:45] <skunkworks_> I bet that would be a trip
[13:57:10] <cradek> jeff's station wagon is huge, it'll be fine
[13:57:38] <jepler> cradek: it's your 600LB server computer that will be killing our gas mileage
[13:57:56] <cradek> hope we can make it up the hills in iowa
[13:58:06] <jepler> indeed
[13:58:21] <jepler> I'm sure we can, but going 45 we might get rear ended by the semis booking along at 60
[13:58:44] <skunkworks_> what brand of station wagon?
[13:59:00] <cradek> it's a '78 lime green vista cruiser
[13:59:06] <skunkworks_> right
[13:59:08] <jepler> cradek is telling fibs
[13:59:19] <jepler> '99 subaru
[13:59:42] <skunkworks_> ah - we have a 98 subaru forester... SO how much oil does yours leak?
[14:00:21] <jepler> haven't had a problem
[14:01:10] <skunkworks_> Nice
[14:01:20] <skunkworks_> we have pistion slap :o
[14:11:48] <jepler> cradek: which 'etags' did you write the rule for?
[14:11:57] <jepler> I just saw this error running 'make tags' on an ubuntu 6.06 machine:
[14:11:58] <jepler> find . -type f -name '*.[ch]' |xargs etags -l c --append
[14:11:58] <jepler> etags: Unknown option: -l
[14:11:59] <cradek> uhh
[14:12:11] <cradek> etags: option requires an argument -- l
[14:12:35] <cradek> etags (GNU Emacs 21.4.18)
[14:12:58] <cradek> xemacs21-bin: /usr/bin/etags.xemacs21
[14:13:31] <jepler> lrwxrwxrwx 1 root root 24 2007-06-01 11:04 /etc/alternatives/etags -> /usr/bin/ctags-exuberant
[14:13:36] <jepler> lrwxrwxrwx 1 root root 23 2007-01-08 19:31 /usr/bin/etags -> /etc/alternatives/etags
[14:13:45] <cradek> hmm
[14:13:52] <cradek> I doubt '-l c' is needed
[14:14:01] <cradek> didn't we fix this once already?
[14:14:10] <jepler> I dunno
[14:15:24] <cradek> you could just add - to those lines if you want
[14:15:32] <cradek> doubt anyone will use etags who isn't using emacs
[16:05:49] <jepler> cradek: http://emergent.unpy.net/files/sandbox/css.png -- top trace is spindle speed out, bottom trace is X position (with motor offset applied; it was actually moving from 1.5 to 0.5 inches from the presumed center of rotation during that trace)
[16:06:21] <jepler> at the end of the trace you can see the maximum requested RPM speed (2000RPM) was reached
[16:07:14] <cradek> yay - so it's done?
[16:07:30] <jepler> the realtime part is
[16:07:59] <jepler> now you just need to get it these numbers, which are currently hard-coded:
[16:08:08] <jepler> css_enable, css_factor, css_min, css_offset
[16:09:08] <jepler> http://pastebin.ca/548029
[16:09:39] <jepler> I'm not at all sure how to calculate css_factor
[16:10:31] <cradek> well that's pretty neat, we've begun the journey of a thousand miles
[16:11:55] <jepler> hah
[16:12:04] <jepler> you snoozed and missed the chance to do the easy part
[16:12:13] <cradek> yeah
[16:13:19] <jepler> G92 S3000 (Sets the max rpm to 3000rpm)
[16:13:19] <jepler> G96 F0.25 (Sets feedrate to 0.25 units/rev)
[16:13:20] <jepler> G97 S200 (Sets speed to 200 CSS (typically meters/min))
[16:13:26] <jepler> ^^ from http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Lathe_Advanced_Features
[16:13:48] <jepler> G92 huh?
[16:14:02] <cradek> wah
[16:14:15] <cradek> G9992
[16:17:21] <cradek> why is it not a straight line?
[16:17:25] <jepler> I think the minute should be redefined so that 10RPM is exactly 1 radian per second
[16:17:54] <jepler> I think that would involve making it exactly 62.8... seconds long
[16:18:51] <cradek> isn't r ~ d ~ circumference ~ surface speed
[16:19:59] <jepler> at radius=0 you have to spin infinitely fast
[16:20:09] <jepler> so I figured the speed had to be css_factor / radius
[16:20:46] <cradek> hmm ok
[16:21:30] <jepler> you spin at 100RPM with radius=1, 200RPM with radius=1/2 and 400RPM with radius=1/4
[16:22:11] <cradek> ok you're right
[16:23:53] <jepler> phew
[16:24:15] <jepler> my thinking was pretty fuzzy
[16:24:20] <cradek> hungry
[20:21:11] <Gran3D> would like to become developer. How to begin?
[20:24:21] <cradek> what would you like to contribute?
[20:25:21] <Gran3D> what's needed? I know G-code, programming, assembler, and some machining. Also have cnc tabletop
[20:26:36] <cradek> how are you using EMC2 now?
[20:27:31] <Gran3D> Have just loaded EMC2 onto Dell Laptop, and hope to connect to mill Saturday.
[20:28:01] <cradek> sorry, it's unusual to have someone want to be a developer who doesn't have a particular enhancement/project/bugfix in mind, I'm just wondering what your plans would be
[20:28:38] <Gran3D> Plan to build Bipod mill, and expect to have to modify Hal to suit
[20:29:01] <cradek> for the first few things, we ask a new person to send patches to an existing developer, and if all goes well we give developer status and cvs access afterward
[20:29:16] <Gran3D> Safe.
[20:31:45] <cradek> what is Bipod?
[20:32:22] <Gran3D> I believe I have a copy of 2.1.5 correctly loaded. First time. Unsure
[20:35:46] <Gran3D> Bipod. Two struts (joints?) driving a spindle in the XY plane
[20:53:13] <Gran3D> re
[21:19:11] <Gran3D> bye all
[21:46:08] <Gran3D> Was there some original EMC development with a bipod device?
[22:19:43] <jepler> I think a kind of bipod kinematics may be used as an example of writing a kinematics module (due to its simplicity) but I don't know of anyone who has actually used such a device.
[22:19:58] <jepler> http://linuxcnc.org/docs/2.1/html/motion/kinematics/index.html
[22:40:37] <Gran3D> Thanks for the reference. I'll sign off and investigate
[23:53:12] <jmkasunich> alex made a tripod
[23:53:19] <jmkasunich> no bipods that I know of
[23:57:24] <jepler> hi jmkasunich
[23:57:28] <jepler> when do you start driving?
[23:57:27] <jmkasunich> hi
[23:57:34] <jmkasunich> saturday morning
[23:57:47] <jmkasunich> I'm on vacation as of 2 hours ago tho ;-)
[23:57:55] <jepler> yay
[23:58:12] <jmkasunich> tomorrow's gonna be busy
[23:58:27] <jmkasunich> visit HGR, mow the grass, pack the truck
[23:58:53] <jmkasunich> that last one is a major project, since it invilves shutting down and packing up computers and such
[23:59:12] <jepler> I am not sure if chris and I are going to load the car tomorrow afternoon or saturday morning
[23:59:40] <jmkasunich> every time I've loaded on saturday, I wind up leaving late and tired, and arriving well after dark
[23:59:49] <jmkasunich> I'd like to get there in time for dinner for a change