#emc | Logs for 2009-05-21

[00:18:25] <eric_unterhausen> how do you take a good picture of a shiny chrome object? reflections make it look horrible
[01:07:51] <jmkasunich> eric_unterhausen: light tent
[01:08:23] <jmkasunich> sigh - someday I'll actually be prepared for something, instead of running around like a crazy person at the last minute
[01:59:27] <tomp> tomp is now known as tom3p
[02:12:05] <maddash> holy shit, google is down again
[02:12:44] <jmkasunich> not here
[02:13:13] <maddash> it's back up
[04:39:23] <cradek> hello from mpm!
[04:50:26] <SWPLinux> hello from Dallas!
[04:51:07] <cradek> hi!
[04:51:11] <SWPLinux> hey cradek, do you have any suggestions for getting ssh to work from within a script (and not prompt for a password)?
[04:51:13] <SWPLinux> hi!
[04:51:18] <SWPLinux> how's the weather there?
[04:51:25] <cradek> I forget the fibal decision - are you coming?
[04:51:29] <cradek> nice
[04:51:33] <cradek> final
[04:51:48] <SWPLinux> uh, well. if things work tomorrow (they didn't quite today), then yes
[04:52:03] <cradek> cool, I guess
[04:52:23] <SWPLinux> I think I have the answer though - it seems that udev permissions are a little different when remotely connected rather than local
[04:52:26] <SWPLinux> or something like that
[04:53:53] <SWPLinux> I ask the ssh question because anything I do needs to be done on 12 headless computers, so making a "foreach computer xxx" script would be a big help
[04:54:55] <cradek> ssh-keygen, then copy that to the target's authorized_keys
[04:55:25] <SWPLinux> oh. is it that simple?
[04:55:29] <SWPLinux> hmmm
[04:56:35] <SWPLinux> I suppose it must be, or our CVS access would be a lot harder
[05:00:17] <SWPLinux> well, bedtime. thanks for the ssh pointers
[05:00:25] <SWPLinux> enjoy Wichita :)
[05:04:54] <cradek> me too, goodnight
[07:15:33] <micges> good morning
[07:29:06] <alex_joni> hello
[07:30:22] <toastydeath> launch all "zig"
[07:30:41] <alex_joni> zat
[09:17:13] <piasdom> g'mornin all
[11:33:07] <alex_joni> so much for security http://www.theregister.co.uk/2009/05/21/lost_white_house_hard_drive/
[11:54:13] <archivist_emc> alex_joni, http://news.bbc.co.uk/1/hi/england/derbyshire/8058784.stm
[11:54:19] <archivist_emc> near to us
[11:59:36] <Valen> got mahself a new 24" LCD
[11:59:39] <Valen> its pretttty big
[13:36:46] <skunkworks892> well - are people waking up at the fest yet?
[13:36:50] <skunkworks892> ;)
[13:39:10] <archivist> no ...waaaaaaaaaaaaaaaaaaaaaa
[13:39:31] <Optic> COFFEE
[13:39:49] <archivist> but I do have 5 axis movement now
[13:43:56] <skunkworks892> archivist: what ended up being the problem?
[13:44:41] <archivist> I have up on that card and stole some more pins from the first parport
[13:46:22] <archivist> so no chance of homing and safety at the moment
[13:46:24] <Jymmm> thief!
[13:46:45] <Jymmm> archivist What, no BRB???
[13:47:06] <Jymmm> (BRB == Big Red Button)
[13:47:15] <archivist> escape key
[13:47:20] <Jymmm> ew
[13:48:01] <archivist> I did identify a safety concern with axis last night
[13:48:55] <alex_joni> wot kind?
[13:49:11] <Jymmm> Safety Relay are pretty cool, if you can get your pas on one
[13:49:18] <Jymmm> paws
[13:50:05] <Jymmm> alex_joni: The ICKY kind
[13:50:28] <archivist> alex_joni, as there is no current key to jog B I was jogging B with the mouse then pressed a key yo jog another axis at the same time mouse control is lost and B carries on
[13:51:20] <Jymmm> ouch
[13:52:04] <archivist> escape did the right thing and stopped B
[13:52:06] <BJT-Work> alex_joni: http://sourceforge.net/tracker/?func=detail&aid=2786229&group_id=6744&atid=106744
[13:53:41] <archivist> I dont have room for a full 360 degree rotation so it matters to me
[13:53:42] <cradek_> arg, assigned to me!?
[13:53:49] <cradek_> cradek_ is now known as cradek
[13:54:02] <archivist> wernt me guv
[13:54:22] <alex_joni> * alex_joni snickers
[13:54:25] <BJT-Work> automagiclly
[13:54:37] <alex_joni> cradek: that happens if you're on the road too long :P
[13:54:38] <Jymmm> archivist http://cgi.ebay.com/STI-SR06AM-UNIVERSAL-SAFETY-RELAY-UNIT-NIB_W0QQitemZ290289717861QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item43969d9265&_trksid=p3286.m20.l1116
[13:54:47] <Jymmm> great price
[13:54:58] <alex_joni> * alex_joni agrees
[13:55:16] <Jymmm> archivist It's BUY IT NOW too
[13:55:31] <archivist> relays I can get not a problem
[13:55:42] <Jymmm> archivist SAFET RELAY????
[13:55:46] <Jymmm> safety
[13:56:29] <archivist> $31 for shipping no thanks
[13:56:52] <Jymmm> It's still a good price
[13:57:14] <archivist> I have relays and buttons
[13:57:28] <skunkworks892> cradek: how was the drive?
[13:57:47] <Jymmm> archivist you sure?
[13:58:11] <archivist> jymm stop nagging I know what Im doing
[13:58:18] <skunkworks892> heh
[13:58:33] <Jymmm> archivist np
[13:58:53] <Jymmm> SWPadnos: Hey here's a safety relay for $40 NIB... http://cgi.ebay.com/STI-SR06AM-UNIVERSAL-SAFETY-RELAY-UNIT-NIB_W0QQitemZ290289717861QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item43969d9265&_trksid=p3286.m20.l1116
[13:59:21] <Jymmm> SWPadnos: includes shipping
[14:00:24] <Jymmm> archivist Oh, btw... I never trust anyone that says "I know what I'm doing" ;)
[14:00:46] <Jymmm> ...and you forget the "we are professionals
[14:02:18] <alex_joni> Jymmm: is it 2-channel?
[14:02:36] <Jymmm> All I know is that when alex_joni first turned me on to them, I thought the exact safe thing - literally.
[14:03:02] <Jymmm> alex_joni: as in EU specs for redundant ?
[14:03:07] <alex_joni> yeah
[14:03:20] <alex_joni> archivist is in the EU (only just though :)
[14:03:42] <Jymmm> SR06AM Dual-Channel Universal Monitoring Safety Relay
[14:03:50] <Jymmm> http://www.sti.com/relays/SR06AM/
[14:04:09] <Jymmm> alex_joni: looks like it
[14:06:24] <alex_joni> cool deal then
[14:07:09] <Jymmm> Yeah, I thought I could use buttons and latching relay too, until I found a HUGE safety flaw that if the START button gets stuck closed, will fail the safety circuit even if you hit the BRB.
[14:08:01] <cradek> skunkworks892: it was uneventful and pleasant
[14:08:07] <cradek> skunkworks892: which day are you coming again?
[14:08:31] <Jymmm> I think that's why Mariss' E-STOP circuit is no longer on the website.
[14:12:50] <skunkworks892> we are driving down friday
[14:14:10] <skunkworks892> what would be a good remote control for linux? (from a windows box)
[14:14:46] <alex_joni> remote control?
[14:14:55] <alex_joni> ssh?
[14:15:02] <skunkworks892> ssh? ok.
[14:17:02] <Jymmm> skunkworks892: use keys, not passwords is best
[14:17:36] <skunkworks892> we are finally getting back to the mysql project
[14:17:42] <skunkworks892> can't rush into these things
[14:17:54] <Jymmm> skunkworks892: Aso, install DENYHOSTS
[14:18:51] <Jymmm> s/Aso/Also/
[14:20:15] <skunkworks892> Jymmm: thanks
[14:22:57] <Valen> what actually is a saftey relay as relates to how its different to a normal relay?
[14:23:39] <eric_unterhausen> a safety relay is built for interlocks, but it could be used as a normal relay
[14:23:57] <Jymmm> Valen: It's basically setup in such a way that cetain conditions have to exist to reset it
[14:24:10] <Valen> so a normal relay with some logic attached?
[14:24:23] <eric_unterhausen> and a lot of contacts usually
[14:25:08] <Jymmm> Valen: Say you open a cabinet. which shuts the system off. To reset it, you must close the cabinet AND hit a reset button before you can hit a start button (as example)
[14:25:26] <Valen> I see
[14:25:42] <Jymmm> There are vaiations, but you get the basic idea.
[14:25:54] <Valen> a relay with some logic in front of it ;->
[14:25:56] <eric_unterhausen> and the instructions are never that clear :)
[14:26:05] <Valen> my conversion is getting closer wooo ;->
[14:26:13] <eric_unterhausen> wooo
[14:26:20] <Valen> ballscrew mounts are being made, mesa is shipping my stuff friday
[14:26:25] <eric_unterhausen> when you're done, you can come over to my house and help me with mine
[14:26:26] <Jymmm> eric_unterhausen: I honestly think they are, you just have to play around and "get it" first
[14:26:46] <eric_unterhausen> I meant they never are as clear as what you wrote
[14:27:04] <Valen> its probably some form of ladder logic, unless its just simple and or not stuff
[14:27:15] <eric_unterhausen> someone on here had one, and it was a lot of "playing around" before he got it to work
[14:27:28] <Jymmm> eric_unterhausen: Oh, well some times have a way of writing that makes complex things make sense.
[14:27:37] <Valen> use a normal relay and a button, if its simple enough it'll probably work when you need it to ;->
[14:27:59] <eric_unterhausen> safety relays are pretty nice if you can get one on ebay
[14:28:03] <Jymmm> It took me a while too, but I wanted it setup in a specific way.
[14:28:11] <eric_unterhausen> they avoid a lot of wiring
[14:29:25] <Jymmm> What took me the longest to figure out is to have the BRB illuminated when the safety circuit was engaged
[14:29:53] <Valen> I'll have to have a look at one
[14:29:54] <Jymmm> When you hit the button, illuminate the button.
[14:30:25] <Jymmm> and when reset, illuminate the start button when ready.
[14:30:33] <Jymmm> that was a pita
[14:30:48] <alex_joni> * alex_joni passes Jymmm a flashlight
[14:31:17] <Valen> http://shop.ebay.com.au/merchant/duftech_W0QQ_nkwZQQ_armrsZ1QQ_fromZ has some good stuff
[14:31:28] <Jymmm> Nah, I just wat\nted the controls to indicate the status of the sstem at a glance.
[14:31:51] <Valen> i was going to get his brushless servo motors, but he doesnt have the drivers for them and its $400 shipping to get them to the good side of the planet
[14:32:06] <Jymmm> especially since the ESTOP could be trigered by things other than the BRB
[14:36:09] <skunkworks892> cradek: are you at stuarts?
[14:36:18] <cradek> yes
[14:36:50] <skunkworks892> You have been there a few times before - right?
[14:37:14] <cradek> yes, not sure how many
[14:37:26] <skunkworks892> neat
[14:40:02] <skunkworks892> cradek: big question is - how is the internet access? ;)
[14:40:15] <cradek> good now I think, after a few false starts
[14:40:20] <skunkworks892> heh
[14:40:26] <Jymmm> CONNECTED 9600...
[14:40:47] <skunkworks892> buuzzzzzwheeeeeebuzbuzbuzwheeeeee
[14:40:48] <Jymmm> NO CARRIER
[14:54:41] <alex_joni> +++ATZ
[15:03:24] <skunkworks892> woohoo - just got 72 more of the igbt's.
[15:03:46] <archivist> production
[15:07:52] <skunkworks892> about $1 a piece
[15:07:55] <skunkworks892> very happy
[15:10:50] <skunkworks892> the guy seems to have some more.
[15:10:55] <skunkworks892> (in pairs)
[15:13:52] <BJT-Work> http://www.linuxcnc.org/component/option,com_comprofiler/task,userProfile/Itemid,17/user,763/lang,en/
[15:16:39] <skunkworks892> http://cgi.ebay.com/INTERNATIONAL-RECTIFIER-G4PF50WD-LOT-OF-2-NEW_W0QQitemZ250303184291QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3a473b7da3&_trksid=p3911.c0.m14&_trkparms=72%3A1205%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318%7C301%3A1%7C293%3A1%7C294%3A50
[15:21:06] <alex_joni> heh
[16:42:37] <Valen> those are some nice igbt's
[16:43:16] <toastatwork> that's what she said
[16:43:23] <Valen> rofl
[16:47:41] <Valen> digikey 2500 qty price for those is $4.35 or so
[16:47:53] <skunkworks892> those are what I am using in this http://www.electronicsam.com/images/KandT/servostart/schem/latestcurrentlimit/right.JPG
[16:48:30] <Valen> heh you and your phat caps ;-P
[16:49:12] <Valen> running off mains or an isolation / stepdown transformer?
[16:58:39] <jepler> hello from wichita
[16:59:03] <micges> hello
[16:59:19] <micges> will be web camera there ?
[17:00:02] <jepler> micges: I don't know.
[17:00:13] <BJT-Work> hello from Poplar Bluff
[17:00:14] <jepler> there's not much to see, and we're not terribly photogenic
[17:00:31] <micges> hehe
[17:12:04] <steve_stallings> steve_stallings is now known as steves_logging
[17:55:57] <BJT-Work> Dallur: hows the boat?
[18:16:34] <skunkworks892> this is really cool. http://www.cnczone.com/forums/showthread.php?t=81125
[18:16:58] <skunkworks892> he is giving a cpld demo with a microsteping drive as an example.
[18:17:33] <skunkworks892> code circuit and all
[18:18:01] <skunkworks892> marris from gecko drives
[18:33:45] <alex_joni> Currently Active Users Viewing This Thread:
[18:33:52] <alex_joni> .Bubba, .pminmo, .Big John T, .samco, .Mariss Freimanis
[18:33:53] <alex_joni> heh
[18:34:00] <skunkworks892> :)
[18:49:53] <archivist_attic> and an anon over here
[18:50:00] <archivist_attic> :)
[19:09:37] <colin_> does anyone know why the model in puma sim the linear moves arnt striaght ?
[19:20:41] <micges> garage_seb: around ?
[19:29:37] <garage_seb> micges, hi i'm at fest :-)
[19:29:49] <alex_joni> whee
[19:29:57] <alex_joni> getting crowded there
[19:30:11] <alex_joni> colin_: cause the kinematics isn't 100% right
[19:30:20] <alex_joni> or the vismach model isn't 100% up to scale
[19:32:49] <alex_joni> heh, this feels really cheap: http://www.dealextreme.com/details.dx/sku.5831
[19:32:59] <colin_> ok
[19:33:27] <colin_> was just trying to find out if the kine isnt working yet or if its just a model mismatch
[19:34:10] <alex_joni> colin_: that's the best kins that has been contributed to emc2
[19:34:17] <alex_joni> I think it's 10+ years old
[19:34:36] <colin_> just trying to get my head around it
[19:34:41] <colin_> lots of maths in there
[19:35:21] <micges> garage_seb: cool
[19:36:35] <micges> I've readed that you reproduced part of mesa bug ?
[19:37:59] <garage_seb> micges, yes, i'm working on it now :-)
[19:38:02] <garage_seb> watch Trunk :-)
[19:38:23] <skunkworks892> colin: I am pretty sure the model doesn't match up with the kins. (I was going to make hal pass the arm lengths to the vismach but never got to it.)
[19:38:35] <skunkworks892> the scara kins/vismach does that.
[19:38:55] <colin_> ah ok cool
[19:39:21] <colin_> im trying to work out what the hal A2 A3 D2 D3 mean in terms of the arm
[19:40:18] <skunkworks892> http://www.electronicsam.com/images/puma/pumaarm.jpg
[19:41:24] <micges> garage_seb: ok cool
[19:41:27] <skunkworks892> if you do a search for puma - you will find what each length means. (I thougt I had wrote all of the terms on the sheet - I guess I didn't)
[19:41:46] <alex_joni> colin_: you can also search for D_H
[19:41:47] <colin_> yeah i downloaded a pdf
[19:41:51] <alex_joni> Denavitt Hartenberg
[19:41:54] <alex_joni> or something like that
[19:42:04] <colin_> but it didnt seem to match the lengths
[19:42:12] <alex_joni> they defined a standard way of naming the distances between joints
[19:42:25] <colin_> A2 is set at 300
[19:42:37] <alex_joni> seems I only borked an extra 't'
[19:42:38] <alex_joni> http://en.wikipedia.org/wiki/Denavit-Hartenberg_Parameters
[19:42:51] <colin_> but the length for the arm is 432mm ?
[19:43:51] <alex_joni> http://www.bridgeport.edu/sed/risc/html/proj/damir/theory.html
[19:49:35] <colin_> so if A2 and D4 are the arm lenghs
[19:49:39] <alex_joni> colin_: maybe try these: http://www.cs.cmu.edu/~chuck/robotpg/robofaq/12.html
[19:49:40] <colin_> what are the other 2 ?
[19:49:53] <colin_> alex_joni, thanks :)
[19:49:53] <alex_joni> they are not arm lenghts
[19:49:56] <alex_joni> they are offsets
[19:49:59] <colin_> ah
[19:50:16] <alex_joni> you can read about it here: http://www.et.byu.edu/~ered/ME537/Notes/Ch3-537.pdf
[19:50:27] <alex_joni> but things don't quite add up ;)
[19:50:33] <alex_joni> different sources report different values
[19:51:35] <colin_> yeah
[19:51:51] <colin_> http://www.kawasakirobotics.com/PDFs/JS10.pdf
[19:51:55] <colin_> that is the arm iv just aquired
[19:52:01] <alex_joni> colin_: it was the closes to working I could get it without an actual puma around ;)
[19:52:13] <colin_> so im trying to work out what the puma stuff means so i can modify it to suit
[19:52:34] <alex_joni> beware that the puma560 is implemented as a special case of a general serial 6-dof arm
[19:52:49] <colin_> what you mean ?
[19:53:03] <alex_joni> puma only has A2,D2,A3,D3
[19:53:11] <alex_joni> yours might have A4,D4, etc
[19:54:07] <colin_> ok
[19:54:26] <alex_joni> the puma560 has some axes aligned, and thus the math is a bit easier
[19:55:01] <colin_> yes i have that in this arm too
[19:55:03] <alex_joni> I think the rotation point of joint2 is in the same plane as the one for joint0
[19:55:22] <colin_> you can see in the pdf file
[19:55:36] <alex_joni> well.. it's scanned ;)
[19:55:41] <alex_joni> I can only guess
[19:55:56] <alex_joni> but it looks like 0,2 and 5 are colinear in that position
[19:56:22] <colin_> yeh
[19:56:40] <colin_> similar in the axis to the puma from what i can see
[19:57:06] <alex_joni> yup
[19:57:12] <alex_joni> you might be lucky then ;)
[19:58:17] <colin_> if i can get this working as a nice little 5axis mill on the mini arm
[19:58:36] <colin_> ill be happy to try it on a big ABB
[19:59:03] <colin_> i just figure its safer to test on something that cant throw me across the room ;)
[19:59:24] <alex_joni> colin_: keep reading http://www.et.byu.edu/~ered/ME537/Notes/Ch3-537.pdf
[19:59:36] <alex_joni> that should cover most you need to learn before figuring it out
[19:59:44] <colin_> thanks
[20:02:18] <colin_> lots of reading :)
[20:02:30] <colin_> wish id payed more attention in maths
[20:04:04] <colin_> hmm it does seem like the figures in the puma dont match with the real world bot
[20:06:35] <alex_joni> colin_: the issue in emc2 is if the kinematics numbers match the numbers in the vismach model
[20:06:52] <alex_joni> kinematics: http://cvs.linuxcnc.org/cvs/emc2/src/emc/kinematics/pumakins.h?rev=1.2
[20:07:03] <alex_joni> vismach: http://cvs.linuxcnc.org/cvs/emc2/src/hal/user_comps/vismach/pumagui.py?rev=1.1
[20:07:03] <skunkworks892> there really is no scaling in the vismach model
[20:07:09] <colin_> yup im just trying to check those
[20:07:23] <colin_> its the vismach model thats not making much sense to me
[20:07:59] <skunkworks892> iirc jmk just made the model to play with vismach. I don't think he actually scaled it out.
[20:08:01] <colin_> the scara model has assignments to D1, D2 ect
[20:09:53] <colin_> skunkworks, ah that makes sense
[20:10:11] <colin_> im not quite sure how the vismach works from the model file
[20:11:00] <colin_> not much documentation on it as yet
[20:11:56] <alex_joni> colin_: in your place I would start by looking for a 3d model of your bot
[20:12:11] <alex_joni> you can convert that to stl or some other mesh format which vismach can read
[20:12:44] <colin_> i can knock one up in CAD easy enough
[20:13:27] <colin_> in fact i you can get the models for the ABB arms quite easy from there website
[20:13:30] <skunkworks892> colin_: what robot do you have?
[20:13:41] <alex_joni> kawasaki js10 ?
[20:13:57] <colin_> http://www.kawasakirobotics.com/PDFs/JS10.pdf
[20:14:00] <colin_> yup
[20:14:12] <colin_> just want to test it all out on the js10 first
[20:17:17] <alex_joni> this is how it should work: http://download.visualcomponents.net/elib/2009/Brochures/RobotWizardAddOn%20Manual.pdf
[20:17:34] <alex_joni> except that 3D-Create .. the software there, costs about 40k
[20:20:09] <alex_joni> bbl
[20:20:21] <colin_> 40k :P bargain
[20:34:35] <colin_> oh sweet
[20:34:44] <colin_> so vismach just runs stls
[20:56:35] <alex_joni> colin_: not stls but obj's, pretty close though
[20:56:48] <colin_> yeah
[20:56:58] <colin_> ok
[20:57:06] <alex_joni> there's meshlab at sourceforge which can convert to/from most any mesh
[20:58:16] <colin_> looking :)
[22:11:25] <colin_> cant work out what the offsets A3 and D3 are
[22:25:38] <colin_> ah D3 must be the offset from centerline to wrist centerline
[23:03:02] <steves_logging> steves_logging is now known as steve_stallings