1000 steps per rev (10000 per inch) you would need a base period of .00002 - for 150 ipm. That should be doable.
I would think
if I did that right
jepler: you alive?
Ok, that's one dev down.... cradek you alive?
`\x90 is now known as \x90
if I use an encoder, do I still need to home?
homing capabilities, that is
why is that?
encoders are incremental
isn't the point of an encoder to keep track of any lost steps?
ah, ok, then what about an absolute enc?
IF you have an absolute encoder, and IF you have an appropriate driver for that encoder (we don't currently support any absolute encoders) then you wouldn't need to home
absolute encoders are rare, complex, and expensive
and many absolute encoders are only absolute over one rev of the shaft
so they still wouldn't tell you where you are on power-up
since the screw can turn many times over the length of the machine
there's absolutely no way to get out of homing?
you either have to home to use a consistent machine coordinate system, or touch off to use a temporary coordinate system that is related to the part you touched off on
i was going to ask about that "Touch Off" button I saw in AXIS -- does "touch off" == going really close to the part and then issuing a g92?
I don't think it does G92
I don't know exactly what it does, thats a cradek question (or read the fine manual)
no mention of 'touch off' in the wiki, i'll check the user manual
btw, jmkasunich, I haven't heard from you in a while, so, welcome back.
I've been around, a little less than normal maybe (got things going on in real life)
are you familiar with cubic.c? i've a few questions about it.
its after midnight here, time for bed anyway
anon. thanks, anyway.
jmkasunich: seen this? http://pdncons.com/prod12-sd4dp.htm
eheh, is that an FPGA or ASIC?
I'm just reaidng hte PDF now
Rates of 1 to 50,000 steps per second are supported.
isn't that awefully slow?
Our USB-based boards use a USB driver chip for communications with your hosting computer.
provides drivers for operation under Windows , Linux, and
Mac/OS. Our installation disk includes modified copies of their Windows drivers; our newest
boards use a unique ID code which prevents them from being recognized by the default FTDI
drivers. All Linux and Mac/OS customers must download their drivers directly from the
[04:23:39] <Jymmm> http://www.ftdichip.com
site, as we have no support capability for those platforms. They will
also have to special-order the boards from us such that we configure them to respond to the
standard FTDI drivers. Look for the drivers and documentation that relate to their FT232RL
I can't get to that website, but I'm wondering if that chipset (since it has linux drivers) could be used to incorp USB into emc?
why not just use the existing linux usb driver?
fiik... I havne't seen anything usb for emc
Fuck If I know
Hmmm, there's mention of SPI
know of any economically priced high-quality encoders?
realtime/USB/buffering/FIFO/EMC - do not belong in the same line
the cheapest is US Digiyal
Skullworks-PGAB: you reading the PDF too?
* Skullworks-PGAB is reading a pdf - not that one
arghhh damn german encoder
wtf is rs 422? who uses that anymore? geez.
anyone who needs serial data transmission without errors over long distances
say more than 30m of 100ft
think RS422 is good for almost a half mile
or shorter runs in RF noisy locations
sure, too bad i can't interface it w/a parport. looks like this one's going off to ebay.
fits with a adaptor to your serial port
needs power to provide the 20ma line current
damnit -- so there's no way for me to use these with emc2, since there is no hal serial driver (yet)
don't you guys use encoders? which ones do you have?
IIRC the powersupply provides 20ma balanced for the total cable impedence.
* Skullworks-PGAB has some 80's TRW units
but will use US digital
use the E4P for the DRO
(cheaper buy the dozen)
yeah, but are they accurate as these babies: http://www.box.net/shared/8pqg8f7g36
maddash: no index?
Jymmm, what's an index?
let me see if I can find a good explanation
[05:08:52] <Jymmm> http://www.usdigital.com/knowledge/glossary.shtml
alex_joni awake and about?
look what I found http://www.pmccorp.com/products/mfx1040.php
nah, probably like $$$
Skullworks-PGAB: just gimme your cc# and sthu
it'll arrive at your door in 60 -90 days, that's 3 days before the credit collectors come knocking
Skullworks-PGAB: I am now
running away for a while though..
you runner you!
alex_joni: well, you back yet?
lerman_ is now known as lerman
03jepler 07TRUNK * 10emc2/docs/src/config/ini_config.lyx: update discussion of COORDINATES and AXES to match the functionality in the 9axis code
03jepler 07TRUNK * 10emc2/docs/src/config/ini_config.lyx: further update discussion of COORDINATES and AXES to match the functionality in the 9axis code
steves_logging is now known as steve_stallings
skunkworks: Hi; trying to work out nicknames?
does that register a nickname?
* skunkworks is really an IRC newbie.
that just changes your name
this is full of info
[16:36:31] <skunkworks> http://freenode.net/faq.shtml
I'll have a look, thanks. Don't want to stay guest the rest of my life ;-)
you can just change your name by typing the command I posted above
skunkworks is now known as whoami
whoami is now known as skunkworks
Guest118 is now known as richarda
skunkworks: sorry wandered off... told to get the mower in
no need to register nickname then?
Not really - unless your going to send files or private message someone
finally got my encoder outputting pulses, but it seems that the encoding PPR is not an integer multiple of the stepper PPR -- what should I do?
question it - what are you trying to do?
Can't you scale the encoder to what you what?
i don't know what 'scale the encoder' is.
maddash: what was the problem with the encoder yesterday?
skunkworks: the encoder needed a 4.5v-30vdc power supply. i tried to take a shortcut by stealing VDC from a parport output pin. didn't work so well.
Guest118 is now known as richarda
skunkworks: Hi - this is almost a habit!
your sucked in ;)
So what brings you on here?
all the way from the UK
Hoping to learn something/anything
Got my hand up a Hurco at the moment
Thinking of using emc2 as a retrofit?
poor lube on the spindle - scuffing
I have emc2 running now (with help from the user list)
what size machine is this? steppers or servos? (just curious)
a bit heavier than than a bridgeport turret; servos
awallin: have you fitted your vfd yet?
richarda: yes we got a new vector vfd
works very nicely at lower rpm compared to the old V/f
out biggest cutter is a 40mm facemill so that can be run at 3000rpm anyway in aluminium
what size motor?
but for steel you might want lower rpm. and then you need torque also at low rpm
now we have a 1.5kW and it has a 1:1 belt so no reduction
I think it's rated at 3000rpm but it can be run up to 5000. you lose some torque but with smaller cutters it doesn't matter
Jari does chamfer milling at the highest setting. probably improves the finish (what would I know about machining...)
you may remember I am considering fitting one
what do you have now?
but the loss of power sub 1500rpm bothers me
to match the variable speed belt I have at the moment
if it's a vector drive then you will get ok torque even at low rpm. The motor might get a bit hot (the current can be monitored from the vfd)
I would need 5hp plus I think
I think ours is an Omron varispeed 7
the one for max 1.5 kW motors was around 300eur as new
as I understand it, constant torque sub 1500rpm, which result in low power at 500 rpm
well, power = rpm x torque, so power is going down anyway when you reduce rpm
if the drive is good it can hold constant torque from zero speed up to the rated speed
max torque at rated speed then gives you the quoted power rating of the motor
it's an Omron Varispeed V7. really compact and has both digital and analog interfaces. I haven't had time to think about interfacing it to emc yet - but probably will someday
I am just looking at my torque/power figures
I reckon with vfd I will only have about 1hp at 500 rpm
compared to 3hp with varispeed belt
yep, running the motor at max rpm and gearing will give you more power and more torque
if the varispeed has a decent efficiency
that's right, it's not that efficient
I guess you just have to over-size the motor when you couple it 1:1...
some commercial machines change from Y- to Delta-winding I think when going from high to low rpm. But you would have to ask a motor exper what that does
infact my existing motor is 3.2hp, to match that at 500rpm with vfd I think you need 10hp, at least on paper
I don't know that much about star/delta, I believe on larger motors you use star for start up
I've got aspare 5hp
and I've been looking at ABB inverters
* skunkworks is glad to have a 10speed gear box..
have you got a 3-phase power-line to your shop?
* skunkworks takes that back.. 16 speed gear box.
skunkworks: where did you find the other 6?
I had forgotten.. ;)
[19:41:24] <skunkworks> http://www.electronicsam.com/images/KandT/conversion/cheatsheet.JPG
2 speed motor - 16 gears. (now it has a vfd)
awallin: problem is, big motors, big vfd'd, big bucks!
skunkworks: is that a universal mill?
* cradek laughs again at FRN = 10*FR/L
That is a kerney and trecker millwaukeematic.. Old.
[19:46:34] <skunkworks> http://www.electronicsam.com/images/KandT/oldkandt.JPG
cradek: I had used that formula so often..
now that is a control!
haha they set the control into the wall for that photo, so you can't tell how huge it is
Worked until a year or so ago :)
cradek: that is the size
oh I thought it went way back past that
[19:49:15] <skunkworks> http://www.electronicsam.com/images/KandT/DSCCurrent.JPG
it's not very deep
the doors are open
yours looks like it goes back for several feet from the front
ohh it's back doors
I see it now
heck it's tiny, it's only a couple feet deep
good for moving metal tho'
It is heavy and takes up a lot of cubic feet of space.
and it has tons of transisters in it.
can't behind the table jig, is that a pc, emc?
Guest402 is now known as rob
richarda: it is a tape emulator. It is in the process of a emc conversion. Slow
got an error running CVS
you can see error output here
[20:05:32] <rob> http://innovative-rc.co.uk/EMC/error.txt
rob: copy the new var file into ~/emc2/configs/orac
since I added UVW axes, the var file changed
how about the nml file
maybe use cvs-head/configs/sim/sim.var
hmm I wonder if I need to fix some others in cvs
will try sim one hang on, tryed nist same
03cradek 07TRUNK * 10emc2/configs/dallur-thc/dallur-advanced.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/boss/boss.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/demo_mazak/demo_mazak.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/demo_sim_cl/demo_sim_cl.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/demo_step_cl/demo_step_cl.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/etch-servo/etch.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/lathe-pluto/emc.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/hexapod-sim/hexapod.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/motenc/motenc.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/m5i20/m5i20.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/nist-lathe/nist-lathe.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/plasma-thc-sim/plasma.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/max/max.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/stepper/stepper.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/stepper-xyza/stepper.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/plasma-thc/plasma.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/scara/scara.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/sim/servo_sim.ini: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/puma/puma.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/univpwm/univpwm.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/ppmc/ppmc.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/univstep/univstep.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/halui_halvcp/sim.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/vti/vti.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/stg/stg.var: fix the many other varfiles (UVW)
03cradek 07TRUNK * 10emc2/configs/stepper-gantry/ (gantry.var stepper.var): fix the many other varfiles (UVW)
rob: fixed, thanks
ye using sim one gets it loaded up
I fixed the rest of them too now
im running cvs as of sunday when i downloaded it
you can come up to date at any time with a simple "cvs update -dP" in that source tree
rnning command now
cradek, after its done do i have to recompile?
can someone re-explain to me why we need realtime interpolation?
why can't we just pre-interpolate everything and leave only the step generation in realtime?
rob: typically yes, but not for this change
maddash: feed override, adaptive feed, synchronized motion (threading/tapping), pause/resume
but isn't feed override just an adjustment to the interval taken between steps?
you could slow down that way, but not speed up, because to speed up the path has to change to honor acceleration constraints
you keep saying "steps" - emc proper (outside of hal) knows nothing about steppers.
indeed. I was thinking along the lines of an adjustment to base-thread
well, this just proves once again that the guy next door is a dumbfuck.
he insists that I could/should give to my super slow P3 computer the job of step generation, and to ignore RT trajectory calcs by pre-calculating all the points on another (faster) machine
I'm sure there are a lot of approaches, I'm just answering questions about EMC's approach
(a P3 is a nice fast computer)
emc's approach is way more elegant. the pre-interpolated steps and time-adjustment feed override method sucks.
P3 isn't fast enough for the encoders
heck, i don't think the parport is even fast enough.
then you need a hardware counter, not a faster computer
counting encoders on the parport is very limiting
great for jogwheels, not so great for motors
what's the max speed on average of the parport microcontroller?
parports don't have microcontrollers
they're just dumb ports on the ISA or PCI bus
if the parport has no independent controller, then why is there a cap on the transfer speeds of EPP and ECP?
I don't know for sure
maybe EPP parports aren't as dumb as I think
but, for encoders you want an FPGA to do the counting
for fast encoders anyway
my calculations: assume 2 inch/sec, (1250 pulses/rev) (1 rev/0.2 inch) (2 inch/sec) = 12500 pulses/sec.
cradek: not fpga4fun.com....
what about a microcontroller?
the pluto (from fpga4fun) does a great job
a microcontroller isn't a very good choice because of their limited speed
40MHz isn't fast enough to keep track of a 12kHz signal?
12kHz is a very slow encoder
a 40MHz microcontroller clock does NOT mean you can read the inputs at 40MHz
but, with an fpga, it does mean that (or some decent multiple of it)
and what microcontroller is 40MHz??
2inch/sec is very slow?
your resolution is pretty low too, many machines have much higher res encoders
[21:00:00] <maddash> http://www.google.com/search?hl=en&client=iceweasel-a&rls=org.debian:en-US:unofficial&sa=X&oi=spell&resnum=0&ct=result&cd=1&q=40+MHz+microcontroller&spell=1
wtf? 2 ips is the max permitted by my series 1 cnc
120ipm, that is.
are PICs even one instruction per clock? you might be surprised how many clocks it takes to decode quadrature
and don't forget you have to DO something with it after you decode it
either way, PICs are the wrong technology for counting encoders quickly
the dsPICs have a built in encoder interface
then suddenly you have a very useful device for motion pid
'digital signal processing' versions
I messed around with one when I thought I would build my own servodrive
something like this is for motor control http://ww1.microchip.com/downloads/en/DeviceDoc/70141D.pdf
has the encoder interface and also six pins of automagic pwm generation
cradek: what is that about the orac?
maddash: fast machines do 3-4 meters/second
feedrates I mean, rapids can be even faster
alex_joni: meters/sec or meters/min?
cardek, i got follwing error when running now http://innovative-rc.co.uk/EMC/emc-error.txt
robh: that doesn't seem like f-error..
robh: mostly laser cutting & the sort
err.. richarda: mostly laser cutting & the sort
alex_joni: hows your USC card doin?
Guy buys a piece of land, guess what he finds... http://www.intuh.net/barnfinds/index.htm
alex_joni: okay, I've still got my head stuck in milling machines ;-)
JymmmEMC: I don't have one
alex_joni: Huh? Who did?
JymmmEMC: I think JMK has one, SWP and an0n
alex_joni: (hey, chnage alex_ to _alex will ya?), I thought you bought one?
JymmmEMC: you're getting all confused lately I see..
alex_ yeah it's all this alex nicks in here
alex_ well, one of you EU ppl bought one, I swore it was you, or ar you pulling my leg?
no, an0nimasu was the one
I only got a mesa
alex_joni: ah anonimasu, ok.
alex_joni: I usually give you a ration of shit, not anonimasu, and I swore it was you
where do i buy these fpga lovelies? ebay/froogle has nothing...
* alex_joni thinks he'll slowly drift away right into bed
goog night all
my god, they're all so expensive!
I love the barn!
toss a mezzine in there too =)
and even an escalator =)
the stairless kind
aka moving sidewalk
40000ns base-thread runs at 40 MHz, right?
[21:53:53] <JymmmEMC> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?PulseRates
hey petev robin_sz
JymmmEMC, sorry to confuse you
alex_ is now known as The_Ball_