#emc | Logs for 2005-09-11

[00:03:40] <robin_sz> only us chickens
[00:12:23] <Jacky^> hey,
[00:12:55] <Jacky^> was wathing on tv the new 9/11 of president bush
[00:13:06] <Jacky^> a dossier on katrina disaster
[00:13:20] <Jacky^> ciao anna_emc
[00:13:50] <anna_emc> ciao
[00:38:08] <Jacky^> g night all
[00:39:42] <anna_emc> night
[01:33:41] <AchiestDragon> robin_sz: you there ?
[01:38:53] <AchiestDragon> :( well stoped work for tonight , need to use a drill , guess the neigbours would complain if i started drilling at 1:18am
[10:55:38] <robin_sz> meep?
[11:41:34] <Jacky^> morning
[12:22:26] <ValarQ> Jacky^: g'day
[12:23:32] <Jacky^> hi ValarQ :)
[12:24:35] <ValarQ> i wrote a hal module this morning :)
[12:25:09] <ValarQ> for simple controlling of PWM servos
[12:25:51] <Jacky^> oh.. nice
[12:26:18] <ValarQ> yeah, i was a bit surprised, i thought it would be harder than it was
[12:26:18] <Jacky^> clock-direction ?
[12:27:32] <ValarQ> no, i have only done static positioning
[12:28:21] <ValarQ> it is going to be connected to a valve later...
[12:28:37] <Jacky^> good
[12:29:47] <ValarQ> had some problems with the resolution thought
[12:30:16] <Jacky^> steps resolutions ?
[12:30:33] <ValarQ> maybe it's a bad idea to use the parport for creating such signals
[12:32:05] <Jacky^> i agreed, in some case its better to get signals directly from a driver..
[12:33:02] <Jacky^> but it coud be required a complex servodrive cricuit :\
[12:34:34] <ValarQ> yeah, this hal component did the job pretty ok thought
[12:49:19] <Imperator_> ValarQ: use this Mesanet 5i20 kard for that !!
[12:49:30] <Imperator_> card
[13:56:49] <mshaver> mshaver is now known as mshaver_away
[15:00:42] <rayh> moin moin
[15:00:50] <dan_falck> hi ray
[15:01:12] <rayh> Hi Dan. Figured you'd be sleeping in
[15:01:39] <dan_falck> no. I'm going back out to my shop momentarily
[15:01:48] <dan_falck> been making parts again
[15:02:07] <dan_falck> how are you doing?
[15:02:56] <rayh> Going well.
[15:03:30] <rayh> How's the bpt?
[15:04:05] <dan_falck> working pretty well. I have 2 Kurt vises on the table, using multi fixture offsets
[15:04:29] <dan_falck> only thing I'm not real happy about is the X axis ball screw
[15:04:45] <dan_falck> It's ground thread, but been abused with chips inside it
[15:04:58] <dan_falck> so theres some fretting in the ball nut
[15:05:16] <dan_falck> I'll have to swap it out sometime
[15:05:59] <dan_falck> but overall I really like having a Bridgeport
[15:06:10] <dan_falck> much nicer than the old mill/drill
[15:06:48] <rayh> Great. I like em also.
[15:07:42] <rayh> Sounds like an abuse of air for blowing chips away.
[15:08:01] <dan_falck> yep. the guy was air nozzle happy
[15:08:28] <dan_falck> I cleaned 2.5 gallons of chips out of the knee
[15:08:39] <dan_falck> I was amazed
[15:09:16] <rayh> Yep. Had a couple of those kinds of knees with the hydrapoints.
[15:09:54] <dan_falck> I like the centroid control that's on this mill
[15:10:02] <dan_falck> it's really handy
[15:10:14] <rayh> I've seen some where the knee bevel gear was clogged.
[15:10:35] <dan_falck> this one is DOS based, but I see that Centroid is doing a Linux based machine now
[15:10:44] <rayh> I used Roland's centroid a bit.
[15:11:04] <rayh> are these servo motors or steppers
[15:11:11] <dan_falck> servos
[15:11:19] <dan_falck> SEMs
[15:11:25] <rayh> Okay.
[15:11:42] <dan_falck> pretty hefty ones
[15:12:05] <dan_falck> it looks like I'm getting 250 ipm rapids
[15:12:09] <rayh> Are the drives enclosed in the centroid or external/
[15:12:31] <dan_falck> the drives are centroid proprietary
[15:12:46] <dan_falck> which is a bummer
[15:12:54] <rayh> Okay.
[15:13:03] <dan_falck> I will contact Roland and ask what he knows about it sometime
[15:13:45] <rayh> That control was one of the things that caused the split between them.
[15:15:09] <dan_falck> well, I hope to make enough money with it to replace the servo amps with copely or something less 'black box'
[15:15:46] <rayh> Right. That would give you the flexibility to experiment with systems.
[15:17:29] <dan_falck> well, I must make some coffee
[15:17:38] <dan_falck> good chatting with you Ray
[15:17:47] <rayh> Don't work to hard today.
[15:34:59] <rayh> Wow. The revised restart from line and the verify are awesome.
[15:36:57] <rayh> Thanks Steven, Paul, Matt.
[15:45:33] <rayh> That was cute. Running emc, downloading, writing lyx -- IRC and emc crashed.
[15:46:20] <rayh> Hi Robin.
[15:46:26] <robin_sz> hi rayh
[15:46:52] <robin_sz> all well with you?
[15:47:04] <rayh> is http://wiki.linuxcnc.org served from your site?
[15:47:08] <robin_sz> yep
[15:47:18] <rayh> Things are going rather well, thanks.
[15:47:24] <robin_sz> good
[15:48:04] <rayh> If we need images but don't have a server elsewhere, can we send them to you and use a stock image directory.
[15:48:16] <robin_sz> sure ...
[15:48:19] <robin_sz> infact ...
[15:48:30] <robin_sz> there is a possibility to allow uploads via thw wiki
[15:48:50] <robin_sz> or by email ...
[15:48:51] <rayh> really. That would be awesome.
[15:49:33] <robin_sz> somwhere .. there is a script I can link to an address, you mail the image to someSpecialName@wiki.linuxcnc.org and it mails back the URL
[15:50:03] <rayh> That would do it!
[15:50:19] <robin_sz> let me go look through the config first, see if I can find the ting in the wiki
[15:50:32] <rayh> k
[15:50:37] <rayh> How you doing?
[15:50:47] <robin_sz> struggling on ...
[15:51:03] <robin_sz> trying to run two jobs at the same time and a young family
[15:51:04] <rayh> Swiss or elsewhere?
[15:51:13] <robin_sz> Uk at the moment, was in NYC last week
[15:51:18] <robin_sz> geneva next week
[15:51:49] <rayh> You'll need your own Jet soon. With a workstation and shop!
[15:52:01] <robin_sz> heh
[15:52:10] <robin_sz> I need another 8 hrs a day
[15:52:22] <robin_sz> you know, for a while I thought I found them too
[15:52:27] <rayh> I know that feeling.
[15:52:33] <robin_sz> I just started using the ones I had used for sleep, for work
[15:52:37] <rayh> How uppers?
[15:53:01] <robin_sz> nah, 6L of Coca Cola :)
[15:53:30] <rayh> That buz is heard to keep up for more than a few days.
[15:53:42] <robin_sz> yeah
[15:53:50] <rayh> And it's cost gets greater as you age.
[15:57:58] <robin_sz> OK, uploads enabled on the wiki
[15:58:20] <robin_sz> 200K max
[15:58:25] <robin_sz> per upload
[15:59:03] <robin_sz> we'll see how it goes .. if it atteacts warez and pr0n, I'll restrict it to editors and admins OK?
[15:59:34] <rayh> The restriction would probably be good to do now.
[16:00:10] <rayh> What is the process for upload? or will you add that to the edit info page?
[16:00:32] <robin_sz> well, go look at the wiki ... see the top line where it says "upload" ?
[16:00:51] <rayh> Ah. I need to read.
[16:01:21] <robin_sz> when its uploaded, it gives you back a wiki link
[16:02:02] <rayh> Nice. That will work really well. Thanks for this, Robin.
[16:02:13] <robin_sz> no problem, just a moments worth of config
[16:02:31] <rayh> Gotta help a neighbor for a bit. Will watch
[16:02:37] <robin_sz> k
[16:02:41] <rayh> rayh is now known as rayh-away
[16:23:38] <dave-e> hi john
[16:24:07] <jmkasunich> hi dave
[16:24:18] <dave-e> wanted to ask some more questions
[16:24:29] <jmkasunich> I talked to Ray on the phone last night bout Rolands mazak
[16:24:38] <dave-e> and?
[16:24:49] <jmkasunich> tentatively I'll be going out the week of Oct 8
[16:24:57] <dave-e> good
[16:25:03] <jmkasunich> Ray and Matt may arrive the preceding week to wire things
[16:25:10] <robin_sz> with an umbrella?
[16:25:43] <jmkasunich> we're leaning toward DC input drives, I think I can scrounge the PS parts (3-phase bridge rectifier, caps, etc)
[16:25:47] <jmkasunich> umbrella?
[16:25:48] <dave-e> at least they should ot need AC
[16:25:58] <robin_sz> rainy season isn't it?
[16:26:10] <jmkasunich> dunno
[16:26:27] <dave-e> should be wonderful weather at least in comparison
[16:26:30] <jmkasunich> beats hot season anyway...
[16:26:40] <jmkasunich> a roof stops rain, but not heat
[16:26:44] <robin_sz> true enough
[16:27:22] <dave-e> changing the taps on the power transformer will get you about 110 vdc off the power supply
[16:27:44] <jmkasunich> oh... I thought we could get lower
[16:27:47] <dave-e> ie use 275 v taps on the transformer and remember to move both ends
[16:28:38] <dave-e> well it would come down a bit if your power is 230 not 240
[16:30:49] <dave-e> jmk...how did you implement the jog end of the panel jog encoder on the mazak/
[16:31:14] <jmkasunich> haven't yet... will work on that
[16:31:27] <jmkasunich> I just have the encoder routed to the PC and a HAL counter counting it
[16:31:40] <jmkasunich> converting to NML jog commands is yet to be done
[16:32:06] <robin_sz> handwheels are a long wanted addition
[16:32:13] <dave-e> OK, that was really my question.......simple send nml jog commands to the system
[16:32:36] <robin_sz> I know its been done before, but it will be nice to do it right
[16:33:13] <jmkasunich> I'm thinking of a small GUI widget with buttons for X,Y,Z, and x1,x10,x100, plus a HAL connector for the wheel input
[16:33:55] <dave-e> another dumb question....why didn't you use encoder(3) since its dac is already used for spindle
[16:34:39] <jmkasunich> the joghweel doesn't require that kind of count rate, better to keep that encoder counter for the spindle encoder
[16:34:48] <dave-e> ok
[16:36:30] <dave-e> jmk...I've been running my mazak at 127 vdc on the servo drives with no problems but tried moving the taps on the transformer the other day.
[16:38:36] <robin_sz> you know,
[16:38:54] <robin_sz> the nicest jog controls Ive used have been on pro video machines
[16:39:00] <robin_sz> spin to jog,
[16:39:13] <robin_sz> press and release and it changes into a shuttle control
[16:39:29] <robin_sz> 270 degree movement, centre detent
[16:40:00] <jmkasunich> ahh... just have to scavange a video board for the control then
[16:43:38] <robin_sz> I used to swap them out of Sony Betacam editors all the time at the BBC, bet they are impossible to buy though ...
[16:51:44] <rayh-away> rayh-away is now known as rayh
[16:52:04] <rayh> /msg NickServ IDENTIFY swanlake
[16:52:21] <rayh> Hi John
[16:52:25] <jmkasunich> hi ray
[16:52:33] <rayh> Looks like I just missed Dave.
[16:52:42] <jmkasunich> yeah
[16:55:01] <robin_sz> * robin_sz writes down ray's password for future use
[16:55:58] <rayh> Hi Robin
[16:56:11] <robin_sz> dotn you just hate it when you do that?
[16:56:26] <rayh> something I should know here?
[16:56:50] <jmkasunich> you must have put a space before "/msg nickserv blah, blah"
[16:56:56] <jmkasunich> because it appeared on the channel
[16:57:17] <rayh> oh. No problem. Anyone can use my name.
[16:57:38] <rayh> /msg NickServ IDENTIFY swanlake
[16:57:55] <jmkasunich> you did it again...
[16:57:56] <rayh> same thing. don't think it wants to do that.
[16:58:39] <jmkasunich> try /msg jmkasunich
[16:58:59] <robin_sz> no space before the /
[16:59:06] <rayh> Got it.
[16:59:24] <robin_sz> the / must be the first on the line
[16:59:44] <rayh> I should link away with me, eh.
[17:02:51] <jmkasunich> ray... I was just thinking about spindle orient
[17:03:11] <jmkasunich> in addition to tool change, there is another application - undercuts
[17:04:16] <jmkasunich> dunno if I'm using the right terminology... single point tool that is oriented, inserted in a hole, then use to back spotface or whatever, then oriented again to remove it
[17:07:30] <paul_c> BAck boring
[17:07:40] <jmkasunich> hi paul
[17:07:58] <paul_c> One of the G8x canned cycles defined for that task.
[17:09:38] <rayh> Yep. It's there.
[17:11:33] <jmkasunich> so when you run the canned cycle it sends a NML to the IO task to orient the spindle?
[17:11:59] <rayh> rayh is now known as rayh-away
[17:12:06] <paul_c> Don't think it was ever fully implemented.
[17:13:37] <rayh-away> rayh-away is now known as rayh
[17:14:30] <jmkasunich> some truly impressive CNC work: http://www.cncgunsmithing.com/projects/1911a1frame.html
[17:31:45] <rayh> paul_c: I installed the latest emc 1.0.26 or such from the repository.
[17:32:04] <rayh> It also shows an update to the kernel modules
[17:32:28] <rayh> Got that as well. Chips.ngc works great now.
[17:37:26] <paul_c> Had a couple of days where neuron.com wasn't synching with the repository here
[17:38:07] <rayh> I'm not certain where I got it. I had both in the source list.
[17:38:18] <rayh> Man that restart works great.
[17:38:28] <rayh> As does the verify.
[17:38:56] <paul_c> Try verifying a file with a duff line
[17:39:09] <rayh> k
[17:39:40] <paul_c> insert G0G30Z1
[17:41:53] <rayh> 1 - line 4211: Unknown word where unary operation could be
[17:42:27] <rayh> I used a g0 fxx
[17:42:28] <paul_c> "line 4211" is a new addition
[17:42:38] <rayh> Yep
[17:42:55] <paul_c> doesn't relate to N words...
[17:42:56] <rayh> does it display N## if one is available?
[17:43:02] <paul_c> nope.
[17:43:27] <rayh> kwrite has line numbering available.
[17:43:32] <paul_c> the interp doesn't pass N words back
[17:43:46] <rayh> Perhaps we should make a similar thing available in the editor?
[17:43:58] <rayh> Right I forgot that notation.
[17:44:24] <paul_c> Not tonight.... I must get this build finished for Craig.
[17:45:02] <rayh> No problem, let me try and do it here.
[17:46:03] <paul_c> Had another bug report on mini earlier....
[17:46:29] <rayh> What was it?
[17:46:33] <paul_c> Highlight a block of text with the mouse, and then delete/undo
[17:46:50] <paul_c> Doesn't delete/undo the expected block
[17:47:18] <paul_c> Use cursor keys to select the text, it works as expected..
[17:47:36] <rayh> I know that I built my own delete/undo cause the text widget didn't have it.
[17:48:00] <rayh> The current tickle does have a good delete/undo so I should update the work.
[17:54:22] <paul_c> Or rewrite it and use Qt libs ?
[17:55:34] <rayh> Is Qt ready for such a full feature thing?
[17:59:20] <paul_c> Qt is.... Not so sure about EMC being ready for a Qt frontend....
[18:22:22] <rayh> Hallo Imperator_
[18:23:03] <Imperator_> hello Rahy
[18:23:14] <Imperator_> Rayh
[18:24:17] <rayh> How are you doing today.
[18:25:32] <Imperator_> I try to finish my PCBs today, but Im to lazy
[18:25:35] <Imperator_> and you
[18:26:09] <rayh> I am a bit lazy also.
[18:26:29] <Imperator_> :-)
[18:26:43] <Imperator_> you have a VIA EPIA Board i heard !!
[18:26:45] <rayh> I was wondering how the fpga project was going?
[18:27:03] <rayh> Yes 2 right now.
[18:27:28] <rayh> I burned up a couple a while back.
[18:27:45] <Imperator_> ups
[18:27:58] <Imperator_> the FPGA stuffis going slowly
[18:28:08] <rayh> I kick myself still.
[18:28:16] <robin_sz> ah yes, the fpga stuff ...
[18:28:25] <rayh> What is the board you are working today.
[18:28:33] <robin_sz> this was the ISA thing, right?
[18:29:07] <robin_sz> I really need a servo amp now to try with the G200X ...
[18:30:03] <robin_sz> needs to be 0-5V and a direction input, rather than +-10
[18:30:29] <rayh> Sort of PWM?
[18:30:48] <Imperator_> nope, a DAC Board for driving real Servo Amps
[18:30:50] <robin_sz> no analogue
[18:30:54] <robin_sz> 0 to 5v
[18:32:12] <Imperator_> that is never used with servo amps, standard is +-10V
[18:32:43] <robin_sz> well, thats the great thing about standards
[18:32:50] <robin_sz> so many to choose from
[18:33:13] <robin_sz> anyway, wont be hard to convert it to 10-0-10
[18:33:40] <Imperator_> thing so
[18:33:46] <Imperator_> think so
[18:33:54] <robin_sz> just needs a cheap and simple pwm amp
[18:34:09] <robin_sz> sort of like a gecko, but just the amp part
[18:35:02] <robin_sz> I keep looking for a simple design and fail to find one
[18:35:18] <robin_sz> couople of IRF530s and a chip sort of thing
[18:36:17] <Imperator_> use a galil 1280
[18:36:27] <Imperator_> 50$ at ebay.com
[18:38:05] <robin_sz> nah, needs to be somehting I can acquire in the UK, preferably in quantity
[18:38:28] <robin_sz> galil doesnt sell much in the UK
[18:41:55] <robin_sz> thats thr trouble with servos, for amateur use there are very limited options
[18:42:34] <robin_sz> theres geckos, which arent real servos and then? pretty much nothing until the "real" stuff
[18:58:59] <Imperator_> rayh: what about performance of that VIA Boards ???
[18:59:50] <rayh> Not at all bad if you don't need a lot of step pulses. 4k at 30 ipm works
[18:59:56] <rayh> servo is great.
[19:00:01] <Imperator_> and which one do you have
[19:00:14] <rayh> I don't see issues here with the onboard video but there may be some.
[19:00:30] <Imperator_> X is ok ?
[19:00:38] <rayh> the 800 MHz EPIA/EPOX
[19:00:40] <paul_c> thassa point... rayh: Is there any update on that Mesa card yet ?
[19:01:20] <rayh> I'll get back to them in the morning and see what's wrong with the delivery or order or what.
[19:01:32] <paul_c> 'k. Thanks.
[19:02:14] <Imperator_> paul_c: do you have ordered some of the mesa boards ?
[19:03:27] <paul_c> via a little place in Michigan, yes
[19:03:49] <Imperator_> ok, what are you planning to do with them ?
[19:04:02] <rayh> I've got the PCI version of "anything IO" running servos here.
[19:04:15] <Imperator_> you know, that we are working on some breakout boards here
[19:04:26] <Imperator_> 5i20
[19:04:45] <Imperator_> with the mesa PWM breakout board ?
[19:05:14] <rayh> Little motors with the 100 watt drivers.
[19:05:22] <Imperator_> ok
[19:05:23] <rayh> rayh is now known as rayh-away
[19:06:13] <paul_c> Might be interested in breakout boards...
[19:06:35] <Imperator_> paul_c: if you wana see our boards, let me know
[19:06:46] <paul_c> * paul_c wanna see.
[19:06:52] <Imperator_> we are nearly ready with them
[19:07:02] <Imperator_> do you have eagle installed ?
[19:07:42] <paul_c> I can instal it easy enough...
[19:16:29] <rayh-away> rayh-away is now known as rayh
[19:16:44] <rayh> Gotta run guys. Thanks.
[19:16:52] <jmkasunich> bye ray
[19:17:37] <Imperator_> hi John
[19:17:46] <jmkasunich> hi Martin
[19:18:13] <Imperator_> how are you
[19:18:23] <jmkasunich> tired ;-)
[19:18:27] <Imperator_> :-)
[19:22:51] <Yuga> hey all
[19:23:33] <robin_sz> hmmm ... i wonder if I can persuade Mariss to do a 10-0-10 version of the G320, without all the encoder and step-counter crap on it?
[19:28:12] <jmkasunich> you mean +/-10V output?
[19:28:29] <robin_sz> no ...
[19:28:33] <robin_sz> anaologu input
[19:28:57] <jmkasunich> sorry, brainfart, I thought you meant a version of the G101
[19:29:01] <robin_sz> ie a real servo amp
[19:29:25] <robin_sz> seems small servo amps are hard to find ...
[19:29:28] <robin_sz> for cheap anyway
[19:33:51] <robin_sz> im beginning to understand why everyone uses steppers for msall machines ... because there arent any small servo amps or motors readily available
[19:39:43] <jmkasunich> yeah... the only small motors I've seen have been salvaged from equipment
[19:40:01] <robin_sz> yeah, that bit is solvable I htink
[19:40:13] <robin_sz> DC motr, add a US Robotics encoder
[19:40:41] <jmkasunich> good quality small motors with rear shaft extensions for encoders don
[19:40:48] <jmkasunich> don't grow on trees either
[19:41:16] <robin_sz> I *think* thats solvable though ... not the hardest part of the equation
[19:41:40] <jmkasunich> well drives can be built
[19:42:01] <jmkasunich> granted, you'd prefer to just buy them... but it is easier to build a small drive than a small motor
[19:42:16] <robin_sz> Ive been searching for a proven H bridge design
[19:42:26] <robin_sz> no luck yet
[19:42:32] <jmkasunich> reverse engineer a gecko
[19:43:00] <robin_sz> I wa shoping to use the web ...
[19:43:43] <jmkasunich> lazy ;-)
[19:44:00] <robin_sz> nah, intelligent
[19:44:11] <robin_sz> dont re-invent the wheel
[19:44:40] <robin_sz> except .. it seems no one has bothered to document that particular wheel in a place ive looked
[19:46:18] <Imperator_> robin_sz: a DC motor with encoder != servomotor
[19:46:33] <robin_sz> Imperator_: explain
[19:46:57] <Imperator_> in that grman forum, they are developing something like a geck
[19:47:00] <Imperator_> gecko
[19:47:14] <Imperator_> and they had also the problem to find DC servos
[19:47:28] <robin_sz> explain why dc + encoder != servo
[19:47:34] <Imperator_> a normal DC servo with 120W of power is about 500 EUR
[19:48:03] <Imperator_> so they used a normal DC-Motor and added a encoder
[19:48:25] <Imperator_> after one day of working it was gone :-)
[19:48:38] <Imperator_> and it was not that small
[19:48:40] <jmkasunich> what happened?
[19:49:04] <Imperator_> i think the comutator is the problem
[19:49:21] <jmkasunich> or the brushes?
[19:49:21] <Imperator_> don't know it exactly
[19:49:41] <jmkasunich> generic motors might not like repeated direction changes
[19:49:49] <Imperator_> maybe both
[19:50:09] <jmkasunich> old story: I once designed a 300HP DC drive for industrial DC motors
[19:50:10] <Imperator_> jep, i think that is the problem, then it overheats
[19:50:20] <jmkasunich> normal brush life for such motors is a year or more
[19:50:41] <AchiestDragon> dc motors are designed for bursts , as soon as you start using small moves and electric breaking thay dont last
[19:50:51] <jmkasunich> we did a life test of the drive by repeatedly accelling and decelling the motor (using inertia for a load)
[19:50:59] <jmkasunich> brushes wore out in less than a month
[19:51:36] <jmkasunich> because we were running it both directions, the brushes never got a change to "wear in" for either direction
[19:52:30] <AchiestDragon> you realy want brushless motors
[19:52:39] <Imperator_> yes, and a real servo has a very long live ! The brushes are looking not that different !! I have a lot of servos from ebay, some of them have bad magnets, but the comutator and the brushes are looking very good
[19:54:21] <AchiestDragon> but a brushless dc motor , well basicaly is not much diferent from a stepper just with the elecronics built
[19:55:32] <Imperator_> and with a much higher accurency
[19:56:38] <Imperator_> a stepper driver manufactur said to me, that the coils of normal steppers are very inaccurat
[19:56:56] <Imperator_> there is a tollerance of about 5-10%
[19:58:32] <Imperator_> and if you want to have a smooth run, you can't also take the cheap brushless servos used in pic and place machines
[19:59:00] <Imperator_> bu, ok for most hobby useres they are ok
[19:59:06] <Imperator_> but
[20:02:54] <AchiestDragon> using a 3 phase motor or reverceable ac motor as a servo should be ok , would have to gear it down and mount the encoder on the output of the gearbox , electronic breaking should still work also
[20:08:40] <AchiestDragon> 5 to 10% on the coils on a stepper will only affect the max touqe by aprox the same ammount
[20:13:20] <AchiestDragon> why do you dislike steppers so much , speed or cost ?
[20:17:10] <AchiestDragon> btw with a 3 phase motor you should be able to drive it in a simalar way to a stepper , may only get 1 or 2 steps per revoultion from it though
[20:18:08] <AchiestDragon> opps 3 or 6 steps per revolution
[20:18:40] <robin_sz> well, brushless is nice
[20:18:46] <robin_sz> but complex
[20:18:54] <robin_sz> usually need encoders and a tach
[20:19:45] <robin_sz> you use the encoder for position
[20:19:54] <robin_sz> and the tach for commutation in the AC drive
[20:19:59] <AchiestDragon> using ac motors and generating the ac by pulseing dc is easyer , but again thats how a brushless one works anyway
[20:20:14] <robin_sz> exactly
[20:20:30] <robin_sz> you can get great little AC servos
[20:20:33] <robin_sz> I have some ...
[20:20:39] <robin_sz> but they are $$$$$
[20:20:48] <AchiestDragon> using 3 phase mains motors as stepers in the same way works but you may need to gear the output
[20:21:23] <AchiestDragon> and well have to design a 3 phase stepper driving sequence rather than the usual 4
[20:21:36] <robin_sz> and build a 3 phase step drive
[20:21:48] <AchiestDragon> yes
[20:22:08] <robin_sz> so, lets forget thatr then
[20:22:09] <jmkasunich> at least a three phase drive only needs 6 switches, a normal stepper drive needs 8
[20:22:22] <robin_sz> true I guess
[20:22:25] <jmkasunich> but DC brush motors only need 4
[20:22:37] <robin_sz> and there are plastic bricks to do 3 phase drive I guess
[20:22:52] <robin_sz> but I think DC brush is more appropriate for small machines
[20:23:11] <jmkasunich> you've said "small" several times... how small is that?
[20:23:18] <jmkasunich> the bricks aren't what I'd consider small
[20:23:22] <robin_sz> 150W 200W
[20:24:06] <robin_sz> medium sized stepper I guess
[20:24:09] <jmkasunich> 2-3A @ 50-100V then?
[20:24:17] <robin_sz> that sort of thing
[20:24:24] <robin_sz> I was thinking 5A, 60V max
[20:24:29] <robin_sz> (okthats 300W)
[20:24:40] <jmkasunich> ok, I misunderstood you
[20:25:07] <jmkasunich> to me, Gecko is medium, xylotex (2.5A @ 24V) is small (those are stepper drives, but...)
[20:25:09] <robin_sz> sort of 1m^^2 router sort of size
[20:25:11] <AchiestDragon> was thinking something that would do the 300w to 3kw range
[20:25:30] <robin_sz> 3KW is piggin' huge
[20:25:54] <robin_sz> the X on the laser os 3Kw
[20:25:56] <AchiestDragon> well thay shouldent burn the frigging motor out that way
[20:26:08] <robin_sz> moves a 500kg gantry at 60m/minute
[20:27:03] <robin_sz> 3kw is deffo AC drive territory
[20:27:11] <AchiestDragon> although saying that not shure if you can get small power rating 3 phase motors
[20:27:28] <robin_sz> 100 to 500W is DC motor territory
[20:27:51] <robin_sz> and steppers do 0-300W I guess
[20:28:48] <AchiestDragon> well from the point of view of cost , a 3 phase 150w motor may be easyer than a dc motor and a encoder
[20:29:09] <robin_sz> you still need an encoder .. and a tach
[20:29:43] <AchiestDragon> btw you should be able to drive it using 3 switching transistors /fets
[20:30:13] <robin_sz> mmm, 6
[20:30:51] <AchiestDragon> and because your using it in a stepper config drive would be 220 - 240vDC
[20:31:15] <robin_sz> well you wouldnt drive it stepped would you ...
[20:31:23] <robin_sz> it would still be sine wave driven
[20:31:38] <jmkasunich> right - you could think of it as microstepped if you wish
[20:31:53] <jmkasunich> but open loop "stepper" operation of a 3-phase motor would be silly
[20:32:00] <robin_sz> indeed
[20:32:13] <robin_sz> you d be better off with a stepper!
[20:33:16] <robin_sz> open loop, the amount of movement as you put load on it ..
[20:33:22] <robin_sz> could be 60 degrees!
[20:34:19] <AchiestDragon> [19:43] <AchiestDragon> using a 3 phase motor or reverceable ac motor as a servo should be ok , would have to gear it down
[20:34:35] <robin_sz> sigh
[20:35:03] <robin_sz> are you talking about open or closed loop here?
[20:35:10] <AchiestDragon> open
[20:35:15] <robin_sz> 60 degrees ...
[20:35:24] <robin_sz> gear it down waht? 20:1
[20:35:35] <robin_sz> ac motors tend to have heavy rotors
[20:35:47] <robin_sz> does "intertial mis-match" mean anything to you?
[20:36:02] <Imperator_> forget that !!
[20:36:08] <jmkasunich> gear it down to operate a drawbridge maybe
[20:36:19] <robin_sz> * robin_sz nods
[20:36:37] <AchiestDragon> well never said it was perfect
[20:36:39] <robin_sz> open loop aint going to work
[20:37:33] <jmkasunich> robin: Ach did ask a very good question of you a little earlier: why not use steppers
[20:38:10] <Imperator_> a servo is expensive because of precision, smooth operation, a lot of calculation inside of the amp, a good sensor (encoder, tach,...) and so on. A stepper doesent have that all, thats why it is cheap
[20:38:14] <robin_sz> well, I wanted to experiment with the g200x driving servos directly, now it has the high speed PID capability
[20:38:45] <robin_sz> assuming you call 16khz "high speed"
[20:39:48] <jmkasunich> ok, experiments are good... but for "small" (depending on how you define it) steppers probably if you simply want best bang for the buck
[20:39:58] <robin_sz> yeah, I know ...
[20:40:13] <robin_sz> for X and Y I will probably use stepeprs
[20:40:15] <jmkasunich> which explains the lack of small servo drives and motors
[20:40:18] <robin_sz> but for Z ...
[20:40:27] <robin_sz> that is the torch height thing
[20:40:44] <robin_sz> a servo seems more appropraite in some ways
[20:40:47] <AchiestDragon> you know in hard disk drives the head steppers have been replaced with a moving coil type design ,given that a liniear motor (in is bigest form ) can lift a train , it should be posable to do one that could move and position large loads
[20:40:57] <AchiestDragon> would be quick and acurate also
[20:41:05] <robin_sz> yes, they are
[20:41:16] <robin_sz> seen them to 6m/second
[20:41:38] <robin_sz> and 0.001" resolution with 1G or more of accel
[20:43:03] <Imperator_> have sean a lathe with linear motors, that is cool, you cant see it, when it returns to the starting point
[20:43:23] <robin_sz> there was one at the last motion control show
[20:43:31] <robin_sz> on air bearings ...
[20:43:38] <robin_sz> one moment it was here ...
[20:43:42] <robin_sz> the next over there
[20:44:23] <jmkasunich> great for emptying wallets very quiclky too
[20:44:26] <Imperator_> yes, and now think on a real big lathe, making big chips
[20:44:42] <robin_sz> they had a small weight on a string ... acelerate towards it .. stop, push it a little, gently bring it back .. go 2m away and then .. zap ... straight back to it with a 0.005" gap
[20:45:27] <robin_sz> joint demo from Anilam I think and ... that linear encoder lot
[20:45:44] <robin_sz> renishaw
[20:46:29] <alpha> alpha is now known as a-l-p-h-a
[20:46:37] <robin_sz> the problem I see with linear motros in engineerign application like a lathe
[20:46:44] <robin_sz> is .. well, lathes make swarf
[20:46:54] <robin_sz> linear motors are a big magnet with a slot
[20:47:01] <jmkasunich> I gave away two Anilam linear motors, one with renishaw encoder... hope the folks can do something fun with them
[20:53:40] <Imperator_> jmkasunich: we have to talk about that gantry stuff sometimes.
[20:53:57] <Imperator_> we are fiering up our big gantry machine the next time
[20:54:26] <jmkasunich> what do you want to discuss?
[20:54:39] <Imperator_> how to implement it ecactly
[20:54:44] <Imperator_> exactly
[20:55:14] <Imperator_> alex had the idear, to export some slave axis
[20:56:30] <Imperator_> i think a extra type of a joint would be a good idear
[20:56:57] <Imperator_> idea
[20:56:58] <jmkasunich> my inclination is always to deal with things at the lowest level practical
[20:57:08] <Imperator_> in hal
[20:57:16] <jmkasunich> more general than that...
[20:57:39] <Imperator_> servo amp ?
[20:57:45] <jmkasunich> if you can avoid the motion controller needing to treat it as a special axis that is a good thing
[20:58:00] <jmkasunich> but maybe you cant
[20:58:11] <Imperator_> the problem is only homing
[20:58:26] <jmkasunich> the concept of homing currently is a fairly high level, the motion controller only
[20:58:33] <jmkasunich> nothing lower level knows about homing
[20:58:50] <jmkasunich> that may mean that you can't deal with gantry without involving the motion controller
[20:58:59] <jmkasunich> even tho I don't like it
[20:59:02] <Imperator_> after it is homed, i only have to take care that the difference between them is smaler than a given value
[20:59:38] <Imperator_> jep
[21:00:19] <Imperator_> do you have a idea how to solve the problem with the hardware counter
[21:01:18] <jmkasunich> I don't know what problem you are talking about... I haven't thought about gantry in months
[21:01:59] <Imperator_> or more exactly with the ref-switches which are reseting the counters in hardware
[21:02:18] <AchiestDragon> http://www.calinear.com/ ok but how much i wonder
[21:03:23] <jmkasunich> you are using two switches to "de-skew" the axis?
[21:04:15] <Imperator_> jep, but i mean the problem that emc has, when the counters suddenly change to zero
[21:04:52] <Imperator_> then it has a big folowing error, and it starts to move with max. speed
[21:05:59] <Imperator_> havent tryed it up to now, because i cant get the index pulse with my siemens cards, but i think it was reported more than once
[21:06:24] <jmkasunich> in emc2 I have avoided using hardware counter reset for that reason
[21:06:48] <Imperator_> I see that, how is emc1 doing that ?
[21:07:06] <jmkasunich> dunno
[21:07:29] <Imperator_> have to look, but there it is no problem, or ??
[21:07:59] <Imperator_> btw. have you tryed the siemens card ?
[21:08:06] <jmkasunich> no
[21:08:16] <Imperator_> ok
[21:08:34] <jmkasunich> I have done very little lately... very disorganized
[21:10:56] <Imperator_> same here
[21:17:39] <AchiestDragon> robin_sz: i reworked the x axis so it can use slides , waiting for slides to turn up now , should hopefuly have them by the weekend
[21:17:56] <robin_sz> good plan
[21:18:01] <robin_sz> what slide you chose?
[21:18:13] <AchiestDragon> those you showd me n ebay
[21:18:15] <a-l-p-h-a> yummyness http://news.bbc.co.uk/cbbcnews/hi/newsid_4200000/newsid_4209000/4209004.stm
[21:18:54] <robin_sz> the accuride ones?
[21:19:02] <AchiestDragon> yes
[21:19:13] <robin_sz> I thought i suggested those for Z ...
[21:19:28] <robin_sz> but should be OK of X I guess
[21:19:55] <AchiestDragon> also seen a compaq set , 6 slides thinking thay may be better , use all 6 of them
[21:20:26] <robin_sz> drawer runners/slides as rails are a thing that seem to get used
[21:21:03] <robin_sz> I suggested those slides for Z I think, because of the way the ball cage moves about
[21:22:02] <robin_sz> whatever, they should work better than your current arrangemtn I suspect
[21:22:05] <AchiestDragon> the acuride ones are a 2 part one , the compaq ones are 3 so give bigger travel than lenth , but 6 mounted correctly should be ok
[21:22:24] <robin_sz> yeah, its a quesiton of being ingenipous :)
[21:22:43] <AchiestDragon> yes , well y and z are ok , it was x that i was having twist problems with
[21:22:55] <robin_sz> yeah
[21:23:03] <robin_sz> the trick is ...
[21:23:23] <robin_sz> to get as much distance as possible between the front and back carriage/slide/thing
[21:23:28] <a-l-p-h-a> robin_sz, is this working for you? http://sourceforge.net/index.php
[21:24:03] <AchiestDragon> a-l-p-h-a: works here
[21:24:10] <robin_sz> apart from some stuff about hurrican katrina, yes .. its fine
[21:24:30] <a-l-p-h-a> hmm... I get a blank screen
[21:24:30] <jmkasunich> I get a blank page
[21:24:49] <robin_sz> proably a different server
[21:25:04] <jmkasunich> going direct to the EMC page works fine
[21:25:41] <robin_sz> it is stunningly unlikely theat the SF homepage is served by one machine, will be several machines feeding a load balancer
[21:25:48] <robin_sz> I guess theresa duff one out there
[21:25:50] <AchiestDragon> getting a blank page in ie on windows though
[21:26:01] <robin_sz> well, thats easy to cure ;)
[21:26:22] <jmkasunich> repeated hits should be balanced onto different machines tho...
[21:26:31] <robin_sz> yeah, probably
[21:26:42] <robin_sz> the other way to share it out is by DNS ...
[21:26:44] <jmkasunich> did several retries, one worked
[21:26:50] <AchiestDragon> but is fine in konqueror
[21:26:57] <robin_sz> give out different IP to diffeent clients
[21:27:00] <robin_sz> 'k
[21:27:06] <robin_sz> sounds like a coding issue then
[21:27:26] <robin_sz> oh the irony .. works in Moz, not in IE :)
[21:27:40] <AchiestDragon> :)
[21:32:27] <jmkasunich> back in a couple hours
[21:32:38] <jmkasunich> jmkasunich is now known as jmk_away
[21:34:56] <Jacky^> evening
[21:37:44] <robin_sz> * robin_sz checks
[21:37:48] <robin_sz> yes .. yes it is/
[21:38:11] <Jacky^> :D
[22:02:42] <Imperator_> is here somebody who has worked with XILINX CPLDs ???
[22:04:31] <robin_sz> ummm, fpgas yes, cplds no ...
[22:04:47] <robin_sz> and then, only a little bit
[22:06:40] <Imperator_> I wana know if i can use this global IO pins also as normal IOs if i dont need special clock pins and so on in my circuit
[22:08:13] <robin_sz> I think so, global IO is usually used for clock, but you could use it for other things .. its just works out better if you need a clock, to use those specific pins ...
[22:08:21] <robin_sz> thats my understnading anyway
[22:10:12] <Imperator_> have heard the same, but i don't know
[22:11:16] <robin_sz> my understnading was it was distributed as a layer, with guaranteed maximum delay, and handy for the CK inputs on latches etc, but thats all I know
[22:11:39] <robin_sz> heh, try it and see what happens, its re-programmable right?
[22:13:30] <Imperator_> jep, but the PCB is not reprogrammable :-)
[22:13:44] <robin_sz> true
[22:14:23] <Imperator_> i will see
[23:10:53] <Jacky^> i found an old board ..
[23:11:27] <Jacky^> L298 with near an LM339N
[23:11:47] <Jacky^> lm339n seem to be a comparator ..
[23:11:53] <Jacky^> what do ?
[23:12:11] <Jacky^> regulate the current ?
[23:13:12] <Jacky^> has anyone never seen a circuit like that ?
[23:14:07] <Jacky^> the board i found drive 2 cc motors with encoders
[23:14:56] <Jacky^> dc motors*
[23:32:12] <robin_sz> probably current control
[23:32:27] <robin_sz> the 298 can be used to drive DC motors
[23:32:31] <robin_sz> often with ...
[23:32:43] <robin_sz> L69x
[23:32:48] <robin_sz> 698 maybe
[23:33:18] <robin_sz> mm...
[23:33:21] <robin_sz> forgotten the number
[23:33:24] <Jacky^> robin it seem to work very nice
[23:33:40] <Jacky^> i want to analize how it work
[23:33:43] <robin_sz> good
[23:34:10] <Jacky^> if i try to turn the motor in the opposite way wen it run
[23:34:14] <robin_sz> look at LM629 ...
[23:34:21] <Jacky^> it come back
[23:34:33] <robin_sz> yeah, servo control ...
[23:34:34] <Jacky^> to the same poit I moved !
[23:34:39] <Jacky^> cool
[23:34:49] <robin_sz> yep, thats what servos do!
[23:34:58] <Jacky^> great
[23:35:10] <robin_sz> now you need to tell the board to make it move to a new point
[23:35:40] <robin_sz> is there an LM629 on the board?
[23:35:51] <Jacky^> maybe .. a moment
[23:36:11] <robin_sz> or 628 maybe
[23:36:29] <Jacky^> it has an L296 near the PS section,
[23:36:46] <robin_sz> 296? .. wait
[23:36:48] <Jacky^> 2 L298 and 2 LM339N
[23:37:00] <Jacky^> yeah
[23:37:20] <robin_sz> 296 is a regulator
[23:37:55] <Jacky^> ok
[23:38:17] <robin_sz> to make it come back to same point
[23:38:25] <robin_sz> there needs to be a controller chip of some sort
[23:38:38] <les> I have a board with I think 4 lm628 on it
[23:39:04] <les> programmed it a good bit
[23:39:26] <robin_sz> yeah, the 628 and 629 are fairly neat little servo controls .. similar in many wayt to the guts of G320 gecko
[23:39:48] <les> I got about 1 ms servo update
[23:40:02] <Jacky^> the two L298 have pin 2 tiled to pin 14
[23:40:09] <robin_sz> bit slow ...
[23:40:14] <Jacky^> probably to get more current on motors
[23:40:21] <Jacky^> and..
[23:40:26] <robin_sz> les: have you seen what mr Hardy has done with the G200X and pid loops?
[23:41:07] <les> wow. There is a praying mantis sitting on the window sill near my computer....it is over 10 cm long!!!! It is swiveling its head watching me.
[23:41:17] <les> no I haven't
[23:41:18] <Jacky^> encoders have a square wave for step, a square wave for rev., and a sinusoidal output ..
[23:41:21] <robin_sz> coo!
[23:41:25] <robin_sz> phot it now!
[23:41:28] <robin_sz> photo
[23:42:12] <les> I identified the species...It is a chinese mantid. They get as big as15 cm
[23:42:28] <robin_sz> les: hes embedded a simple processor int he FPGA ... seperate data and prog areas, can read the encoder positions and write to the analogue IO ...
[23:42:34] <les> It flew in the door. Ithought it was a bird.
[23:42:37] <robin_sz> update rate is at least 16Khz :)
[23:42:59] <les> oh neat
[23:43:48] <robin_sz> only got a 1kbyte prog segment, but that should be enough I think .. runs around 50mhz from what I remember
[23:44:00] <robin_sz> (most of that is from memory, I could be worng of course)
[23:44:29] <anna_emc> hello
[23:44:30] <robin_sz> which is whay I am trying to find a reference design for a little H bridge servo amp :)
[23:44:36] <Jacky^> ciao anna_emc
[23:44:50] <robin_sz> hej
[23:45:09] <les> hi anna.
[23:45:18] <Jacky^> robin_sz: what do motor came back to the same point ? the software ?
[23:45:20] <anna_emc> hi les
[23:45:43] <robin_sz> Jacky^: there must be a controller of some sort, or even a counter ont he end of the encoder
[23:46:18] <Jacky^> so, the software can 'understand' that and come back ?
[23:46:28] <Jacky^> understood right ?
[23:46:37] <robin_sz> see the block diagram on the LM629 ... if it comes back to the same point when it moves by hand, then there must be some circuit like that onm the board
[23:47:26] <robin_sz> read the position from encoder, comapre to where it should be, generate error signal to drive motor
[23:47:34] <robin_sz> can be software or hardware
[23:47:44] <Jacky^> uhm, ok, the board have many ICs, and eprom above..
[23:47:53] <robin_sz> ah, eprom
[23:47:56] <Jacky^> i will take some photos..
[23:48:03] <robin_sz> so, might have a uP on there?
[23:48:10] <Jacky^> yeah, eprom
[23:48:37] <Jacky^> its look like ols C64 board ..
[23:48:39] <robin_sz> les: anyway, that give the possibilty to drive real servos ...
[23:48:53] <les> I will have to check it out
[23:49:13] <les> still watching that bug....
[23:49:21] <les> biggest bug I ever saw.
[23:49:54] <les> the swiveling head watching me...creepy!
[23:49:55] <robin_sz> les read the latest manual, he refers to it as "white heat" ... his cute name for the embedded processor. its fairly basic, but sounds like it has enough to do pid
[23:50:05] <robin_sz> wow ...
[23:50:11] <robin_sz> we dont getthose over here
[23:50:15] <robin_sz> thank $deity
[23:50:18] <anna_emc> '
[23:50:21] <anna_emc> ?
[23:50:46] <les> chinese mantis were introduced here 100 years ago..and are the largest insect in north america
[23:50:54] <robin_sz> 100mm long in the body and quite fat and juicy?
[23:51:06] <les> no kinda skinny
[23:51:13] <les> picture...
[23:52:09] <les> http://www.cirrusimage.com/mantidae.htm
[23:52:11] <Jacky^> robin_sz: dou you think is it possible to analyze the pulses, with a scope, on L298
[23:52:23] <Jacky^> to understand how is it drived ?
[23:52:35] <Jacky^> or its hard ?
[23:53:59] <Jacky^> les: ouch.. what is ?
[23:54:06] <anna_emc> les bleachhhhhhhhhhhh
[23:54:15] <les> haha
[23:54:28] <Jacky^> :P
[23:54:35] <anna_emc> schifezzaaaaaaaaa
[23:54:50] <Jacky^> anna_emc: understood ..
[23:54:52] <robin_sz> mmm ... big thing
[23:54:53] <Jacky^> :(
[23:55:17] <anna_emc> disgust
[23:55:21] <robin_sz> Jacky^: it will be PWM on one side of the motor, the other side held low, probably
[23:55:24] <Jacky^> lol
[23:55:51] <Jacky^> robin_sz: thanks :)
[23:56:24] <robin_sz> les: do they eat native species?
[23:56:37] <Jacky^> my cousin gave to me these board
[23:56:51] <Jacky^> he want to biuld a plasma cutter ..
[23:57:02] <robin_sz> let me sell him one ;)
[23:57:09] <Jacky^> he think this board its very nice
[23:57:20] <Jacky^> if i can understand how it work ..
[23:57:22] <Jacky^> :\
[23:57:32] <Jacky^> will see
[23:57:46] <robin_sz> les: I saw the other day they have discovered a new way to catch can toads in Aus,
[23:58:00] <robin_sz> seems they are attracted to UV lights at night ...
[23:58:01] <Jacky^> tomorror i will do some photos, so i can show it to you
[23:58:29] <Jacky^> tomorrow *
[23:58:53] <anna_emc> www.windoweb.it/desktop_foto/foto_gatti/Gatti_08.jpg
[23:58:56] <robin_sz> les: trouble with pretty oriental imports, they often upsetthe local foodchain
[23:59:32] <robin_sz> anna_emc: http://www.bonsaikitten.com
[23:59:44] <Jacky^> haha
[23:59:50] <les> mantis are good...you buy egg pods and put them in the garden. They eat bugs and even lizards and small birds