get a dell dude
ok - I have figured out swpadnos looks a bit like the lead singer of the red hot chilli peppers. (without tattoos)
does he have long hair?
4th from the right
[04:14:51] <skunkworks> http://www.electronicsam.com/images/KandT/cncworkshop/cncworkshopemc.jpg
too many beards
linux people. it is required
was that from the most recent gathering?
I was actually looking for beard wax at the store today ...
the goatee is getting out of control
OK - I see Jon to the left of him - who are the others
from the left:
Steve Stallings, Matt Shaver, John Kasunich, Raty Henry, Jon Elson, Me, Dave engvall (I think), Scott Hamilton, Chris Radek
- the t in Ray's name :)
sounds right to me. we should really have a named photo.
you forgot jeff epler
oh - whoops
just after John K
I'd love to attend some of these, but its easier to get a root canal done than to get a week off work it seems.
big typo there :)
tell them you're getting a root canal
fall terminally ill
and then get better
They allready consumed all my PTO with a plant closure from Dec 21 - Jan 2... Trying to earn it back...but its slow going.
ok - what does pto stand for?
paid time off?
yep - combined vacation & sick time
the just call it PTO, pre-excused or not
* ejholmgren_ contemplates bronze bearings running on drill rod
get sick without PTO then its a writeup unless you have written doctors orders or hospital recipts
I must be a cheap-ass
cheaper in lots of 100
in a dirty environment, bronze is better than bearings
bronze pushes crud aside, bearings roll over it (and roll it into the rail if its hard)
I have a Seig X3 / Grizzley I'm retrofitting.
I was thinking about just using precision acme lead screws with anti-backlash nuts.
jmk: will flanged bronze bearings work for linear motion as well?
only see references to radial and thrust
you mean round bearings on round rods?
sure they'll work
its just a matter of details
round rods have limited stiffness - gotta choose a diameter that meets your needs
and round bearings must have some non-zero clearance to slide on the rods, which could allow some shifting
gotta quantify that and decide what is "good enough"
this is my first machine
so anything is good enough
if you are going for very long travel, round rods suck, because with only end support they have to be huge to avoid bending
most other forms of linear guide can be supported all along their length
length will be ~16" or so
using 1/2" diameter
travel, or length?
an 8" long table on a 16" rod will have less than 8" of travel
what do you intend to cut?
pine and ply
and maybe some pcbs
1/2" seems a bit thin
but that can be calculated
* jmkasunich googles
I've considered doubling up on each side of the x axis
go fatter, not more
stiffness goes as the square of diameter
a 3/4" bar is as strong as two 1/2" bars
good to know
aligninment is tricky with two rails, you _don't_ want four
(the rails have to be exactly the same distance apart at both ends, and both sets of bearings need to be exactly the same distance apart too
(I'm assuming two rods, each with two bearings/bushings sliding on it)
pier_port>ejholmgren_: thanks... removing APIC from kernel did the trick...
yay, I acutally helped someone for once
I saw a post where someone used linear ball bearings and they immediately scored the fsck out of the drill rod
bronze should be quite a bit softer than the steel, right?
yes, bronze is softer
jmkasunich: thanks again. got it all tuned again and it's quite snappy now without f-errors. [f-errors about .0005 at .10 jogs at 50ipm]
They also make some nice delrin bearings for this - think the name ins Thompson Drylin or some such.
[04:49:16] <jmkasunich> http://jmkasunich.dyndns.org/pics/CIM-before-final-assy.jpg
that is a round bar slide I made
3/4" bar, about 2" travel
Also - there is a material called CPO - Chromed Polished ground bar - its sold for hydrolic cylinder rod.
but designed for a load of 1000 lbs (it was a lab test jig to stretch things)
I used 1045 TGP (turned ground polished) rod, not very expensive
cost is close to drill rod, but its half hard and available in 10ft lengths
yep - thats the stuff
if I did the math right, a 20 lb load in the middle of a 16" long x 1/2" diameter steel rod that is supported at the ends will deflect it by 0.019 inches
same load on a 1" rod will deflect it about 0.0012"
fatter is definitely better
[05:01:14] <ejholmgren> http://imagebin.org/7271
drives are hooked up
minus the one I accidentally smoked
did you get disconnected?
the other one is on the mac
so you saw the calcs for 1/2" rod?
kvm for the win
not too bad for what I'll be doing
stiffness for a bar goes as the fourth power of the diameter
1/32 = horrible
even if you are doing wood
it's for flat relief woodblock prints
at least go with 3/4"
that will give you 0.0038 deflection with 20 lbs load
fine, I give
3/4" it is
[05:06:46] <ejholmgren> http://imagebin.org/7272
trust me - the additional cost and weight will be worth it in avoided vibration
[05:07:18] <ejholmgren> http://imagebin.org/7273
what are all the outlets for?
relay box is getting wired up for classic ladder
outlets: so I can control _normal_ things ;)
router (spindle) and shopvac for dust?
or normal like non-CNC things?
although stepper-driven dampers would be badass
ejholmgren: even 1" pipe wobbles a lot.. i couldnt cut plastic even
this was something like 30"x20" travel
you can use EMT it might be cheaper, they sell big stuff at most building supplies
fill the tubes with sand
and skate bearings.. i dont really think dust is a huge issue if you're only doing wood
EMT== metal electrical conduit
fenn: pipe or rod?
pipe.. rod is wasted metal and too expensive to get a proper diameter
check the prices on 3" drill rod?
stiffness is the same
I only need about 1/3 of that travel
EMT is too thin until you get over 1.5"
ok, gas pipe then
but I agree on the skate earing idea
but I agree on the skate bearing idea
just not on black (gas) pipe
yes, black pipe, all the galvanized crap makes it uneven
ugh - I'd shell out the cash for DOM tubing before using black pipe.
how then? drill rod bolted to a support structure?
thread the ends
ejholmgren: i mean bolted down every 5 inches or so
bottom supports with open bearings?
have you ever looked at the tolerances on pipe?
will bend 20% when you unclamp it
part tolerances are only part of the picture
how can you get smooth and wobble free travel when your rail isn't neccessarily the same size over its length?
machine the pipe
THAT - is much easier said than done!
how long is it? (sorry, missed the beginning)
16" or so
shouldn't be hard... sign up for a class at a JC and use their lathes...seems to be pretty common for JCs to have a lathe with >30inches
don't really matter much - more than 8" your going to have all sorts of taper/finish issues
two pieces of 3/4" 1045 TGP rod are $15.58 from metal express
thats not each, thats total
follower is the best option
fscking cheapskates using crappy pipe to save a nickel or two
fscking cheapskates with no money
unless you could just start off with gound stock to begin with.
lets just make it out of solid diamond
3/4" W2 isn't that expensive... think it was ~$10 when I got it
TGP is turned, ground, and polished
enco + free shipping on the drill rod
yep - buy the good stuff, you will have enough other details to sweat over.
there are plenty of places where you can save $5 or $10 without making life hard for yourself
jmkasunich: what scale machine are you talking about?
16" might be available as rems
I'm not, ejholmgren is
way i see it, using pipe allows you to mess with the material properties like damping coefficient
preload that sucker
if you can find a source of tubing with an _accurate_ and smooth OD, then more power to you
I have nothing against the rods being hollow, I do have something against the outside being crap
I have 4x 25# bags of lead shot if I want damping...
is lead better then sand for damping?
mass is mass
if you soak the sand in heavy oil you get some viscous damping too.. but mass is more effective
mass alone isn't the answer
damping is good, mass can help, but nothing replaces stiffness
you could just have a heavy bell
hmmm 16".... tried looking at paper towel racks at stores?
sand + lead + oil == toxic waste
also - a good fitting sleeve bearing with an oil film (bronze bushings on TGP bar) has incredibly more damping than point contact (skate bearings on anything)
* Skullworks wonders how he knew my lead ingots all have the term "TOXIC WASTE" cast into them.
skate bearings have only one advantage - they can be open, allowing support along the rail
if the machine is long enough, that is a huge factor
16" is not that long
8" of travel is mighty small
agreed, but not my spec
sherlines have about that on x, less on y and z
jmkasunich: if you were to cut a thread for a leadscrew in a pipe.. what would you use for raw material?
I wouldn't be so insane
is this in the realm of grinding?
most pipe is crappy steel
well, tubing of some sort
something mostly hollow
I'd sooner use allthread
say about 3" dia
you are assuming that time has absolutely no value at all, including time on machines that the average person doesn't even have access to, to save a few bucks
why so big?
it's top secret :P
friction is gonna kill you
nah i'm using roller screws
hmrrnnn ... metalexpress even has stock on 'burb away from me
fenn: I don't think I want to know
a good roller screw needs extreme precision, and very hard steel
if its soft enough to machine, its too soft to make a proper roller screw
you could get hard stuff and grind it, but you are talking about hundreds of dollars worth of grinder time
roller screws, ballscrews, rolling element linear bearings, and skate wheels on pipe all involve point or at best line contact, not area contact
so you get _extremely_ high contact pressure, even at moderate loads
roller screws have less contact pressure than ballscrews
and unless you are using good steel with good heat-treating, you will have fatigue and wear
line vs. point - yes, roller is better
still can't use soft steel and expect long life or accuracy
hence why i'm asking your opinion
acme with bronze is easier to build, cheaper, and if sized right can have reasonable friction
is there such a thing as a hydrostatic leadscrew?
I don't get the desire to use exotic technologies without the corresponding exotic materials and techniques, on what are fundamentally simple machines
I understand that to mean oil pumped under pressure into the bearing/nut
ok, hydrostatic bearings are exotic technology, sure, but roller screws really aren't
roller screws need at least two or three rollers, made of hardened steel, with precise tolerances
an outer shell, and a screw, also hardened, and also precise
backlash in the assembly is gonna be on the same order as the tolerances of the parts, if not worse
you can make anti-backlash nuts
anti-backlash roller nuts?
yeah why not?
why not make antibacklash acme nuts in 1/10th the time and 1/50th the cost
* Skullworks thats my plan...
well, i'd still have to make the leadscrew.. unless they make hollow large diameter acme screws
you need big and hollow for some other reason?
spindle thru the middle or something?
is it sexual?
why the obsession with hollow? - You going to carry this on your back?
big for stiffness with misalignment, hollow to save mass and to fit a viscoelastic shear layer
yes i'm going to carry it on my back
or close enough
have you done the math, or did you pick 3" out of the air?
i picked 3" out of the air
there is a fourth power rule for stiffness vs diameter
so unless you are doing insane things with this, there is no fscking way you need 3"
3" is 256 times stiffer than 3/4"
i look at it in terms of overall proportions
if it doesnt work in a scale model it wont work on a large version
is that wrong?
not everything scales the same
some stuff is proportional to size, some to size squared, some to size cubed, some to size^4
I don't understand what you are actually trying to do, and its 1:40 in the morning, so it doesn't make sense to even talk about it
scale up a bugs exoskeleton... after a point it can't support its own weight
heh thanks for trying anyway
yes eventually you get a spherical planet
speaking of viscoelastic damping - you get that for free with acme screws and bronze sleeve bearings
the oil film has great damping properties
totally unrelated thought -- does the rules of electrostatics allow me to connect a stick to a terminal of a 20KV battery and suck powder out of a metal cup connected to the other terminal of the battery?
it takes current to perform the transfer though
stick = conductive I assume
Wiley E. coyote had it right, ALWAYS USE ACME!
stick as in a brass rod
I see. how does one research this? (tried looking up electrostatics and powder and got no where)
hmm.. maybe send a mail to pete gruendeman
he used to do stuff like that
finally got my geckos mounted to the heatsink
gawd I hate heatsink grease
as in the fellow mentioned in this page? http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?ElectricalDischargeMachining
greundeman at att.net
just att.net? got a hit for world.att.net instead
worldnet I mean
shrug.. try both i guess
worldnet.att.net and att.net mail goes to the same place
'k thanks. as foolish as I will sound, I'll give that a try
(I have that ISP too... you can use jmkasunich at worldnet.att.net if you want extra typing, but att.net works and it what I tell people to use
seem to remember at one point Bell Labs wanted to use that as their internal addresses
[06:51:25] <fenn> http://cache.gizmodo.com/assets/resources/2007/02/pcmaclinux-thumb.jpg
a-l-p-h-a_ is now known as a-l-p-h-a
Anyone know the path to bin/hal_parport?
"The timer was a hall effect probe near a multi pole spinning magnet, and pulse rate could be adjusted by controlling motor speed,"
wow what a bizarre way to build a timer "circuit"
can python interface with a IO port (serial, or parallel?)
there's a nice serial module
reading django tutorial.
s = serial.Serial("/dev/phone", 115200, rtscts=1)
^^ from a little program that reads out my phone's contact list
pyserial is very simple to use
apparently using the PC speaker is a cause of overruns in rtai, on at least some machines
(according to posts to the rtai mailing list in the last 24 hours)
I finally unsubscribed
the docs that went with 2.0 still referred to bin/hal_parport even though it wasn't being built then .. but it looks like that's finally gone from the 2.1 and TRUNK manuals
i have one problem wit emc
in terminal windows..
cant´find "fuser",used to verify that it is safe to shutdown realtime
i compiled emc 2.0.5 in slackware 10.0
that message is very descriptive - you will have to fix it
you can help-me?
i compiled emc 2.0.5 in slackware, but in terminal returns it:
can´t find "fuser"
used to verify that it is safe to shutdown realtime
we know, you said that 4 minutes ago
if you can't fix that kind of simple problem you should use ubuntu, which the emc2 team supports
i use ubuntu
but i like slakcware
you know about this message?
how uninstall emc?
i compiled it and i want unistall
how make it?
taurus and wottan is a company whre we a introduct emc
Wottan is a company made cnc, taurus gun
for this i need one help
how unistall emc
and y try re-compiled
how uninstall emc?
uhm...are you using Ubuntu?
a try in slack
Well, there's no "make uninstall" option, so it isn't that simple
ok...sorry but I'm not an expert...
you can just delete the files that were installed
i enter in directory and make uninstall?
you may have a harder time removing the realtime kernel (if you don't need it)
no. I said there is no make uninstall option, so you have to do it manually
manualy, i delet files?
no compiled for local folder
make an make install
no make run in place
friend thi program is ok
but terminal returns..
fuser is a standard unix/linux program. I don't know why it's not there
i input fuser on terminal..
this ok ins slack
because no ok?
emc alone in ubuntu?
in that case, something is wrong with the realtime system, which may be EMC or RTAI
(or it's just a path problem with the emc script)
i compiled one kernel witt rtai
I don't know how to fix the problem - I only know about fuser from google :)
anyone could help me? I've a question...
I'm learning to use hal
so i'm not very good yet
I'm trying to use hal_joystick to jog my cnc with a USB joypad
everything went well, the hal file work, there is only one pronlem, the jog-scale
Usb joypad works ok?
if I set it from the .hal file using setp axis.0.jog-scale 0.1
the problem being that you can't change it from the joypad?
at this moment...for experiment
I would like to set the scale from the .hal file
but, when I set it, and start EMC2, if I look with halmeter at the jog-scale pin
its value is 0 even if in the hal file it was setted to 0.1
are you talking about axis.N.jog-scale?
now if I change this value using "show hal configuration" where I can execute a command
for example axis.0.jog-scale
how are you going to generate counts for axis.N.jog-counts using the joystick?
with the sim-encoder
and the encoder modules
if I change the scale value from 0 to 0.1 the system works
yes it is interesting because a usb joypad is very inexpensive
do you have a signal hooked to that pin, or are you changing it with setp?
I've puchased mine 5$...so it is good to experiment and learn something about hal
I've setted it with setp in the hal file
setp axis.0.jog-scale 0.1
but hwen EMC2 starts...it resets the value to 0
and jogging doesn't work...
hmmm. how do you set axis.N.jog-scale before EMC2 has started?
it sounds like you're saying that you can set the parameter, but then when you start EMC, it gets reset
but those parameters should only exist after EMC has started
those come from the motion controller (loadrt emcmot)
I tried estop, switching modes, etc, but mine stays at 0.1
I set it in the .hal file that is used when I start EMC2
can you pastebin your hal file? maybe we're missing something
hold on few seconds, I've to tranfer it from my USB pen
well I've the file here
I put that in my startup hal file, and it stays set for me
where can I paste it?
[16:13:04] <SWPadnos> http://pastebin.ca/
never used it...can you explain what have I to do?
just copy the file and paste in the website where it says "paste below"?
copy the text and paste it into the text entry area, then optionally write a description and set an expiration time
once you hit "submit", you'll get a URL you can paste here, and your browser will be redirected to that URL in a few seconds
[16:15:09] <xemet> http://www.pastebin.ca/352092
interesting! useful service!
heh - yep. there's one for images as well
sorry, but I can't see the part of the file where I set the scale...
i have appear this error: emc/iotask/ioControl.cc 846: can't load tool table.
i can solv this problem ?
hold on I check if I took the wrong file...
xemet, I was just going to ask how this file is loaded - is it done with a HALFILE line in the ini?
I see you are making new threads - you should use the threads that the motion controller is already running
[16:21:37] <xemet> http://www.pastebin.ca/352099
the fast one is "base-thread" and the slow one is "servo-thread"
here is the right file
cool, you have a joystick with three axes?
actually four...it is one of those joypad
with two little joystick in the middle
and TEN buttons!
does hal_joystick read the buttons?
I control almost everything!
about the threads...
but, if I create new threads like I have done what is the problem?
I ask because after changing the scale value, the system works
no particular problem, it's just more threads than you need
yeah I still don't see what might cause that value to be lost
uhm...don't ask to me...I started to use hal today for the first time in my life!
it looks like you have an excellent grasp of it already
well, I've read the manual...
using the encoder modules to get counts from an analog input is creative
I would like to build a jogwheel using an optical encoder
I have one of those - it really works great
so I looked at the manual pages where encoders modules was described
and when I've seen that there was an sncoder module and a sim-encoder...
try using a "constant" block to supply 0.1 to a signal, and hook that signal to those scale pins
is it called "constant" or "supply"?
I bet that will fix it, but I don't know why you are having this problem
32780 float OUT 0 constant.0.out
ok - I think it was "supply" as part of blocks
how I load the constant module, just I type "loadrt constant"?
it has a param "value" and a pin "out" that it sets to that value
now I will try
you'll have to add it to a thread with floating point (like servo-thread)
I would like to let you know that in the hal_joystick documentation is written that joystick should be in /dev/js0
while I've discovered that min is in /dev/input/js0
-d device use device as the joystick device (default is /dev/js0).
it must have been /dev/js0 on jmkasunich's machine, hmm
I think he wrote it before he had an Ubuntu install
maybe it should change to match Ubuntu by default
I don't know...at the beginning I was throwing my joypad in the trash...
because I thought it was broken...
xemet: did you have to do anything special in linux to get the joystick driver to work? or did you just plug it into usb and that's all?
I just plugged the usb joypad...
yeah, I think we should change the default then
the device manager see it as generic joystick
that's why it works - the HAL joystick driver uses the device file provided by the system joystick driver
it expects to get "events", it doesn't communicate directly with the hardware
xemet: are you using ubuntu dapper 6.06?
03cradek 07TRUNK * 10emc2/docs/man/man1/hal_joystick.1: xemet reports /dev/input/js0 is the default on ubuntu 6.06
03cradek 07TRUNK * 10emc2/src/hal/user_comps/devices/hal_joystick.c: xemet reports /dev/input/js0 is the default on ubuntu 6.06
now it works...
what was wrong?
I was editing a the hal file in another directory...
none of us have ever done that
forgetting that I had to copy it in the emc2/configs
nope. I never have Kate open with 27 files
6 of which have the same name ... :)
I never forget to compile my changes either
xemet: nice work!
well it works very well now!
maybe I've to adjust scale value for encoders module
I only have 24 terminals open at the moment, but that's because I close most of them before I go home on friday and I haven't opened many yet
but it works...
i got a joystick i bought years ago, an xbox, gotta dig it out :)
maybe I'll fiddle with my force feedback joystick sometime :)
I've only two computers in my room and I get mad going from one to another
and how to hack xbox to usb, there's web sites for it ( has headset too :)
make a crossover patch cable
ah! mine 5$ joypad had forse feedback
a joypad with force feedback? never heard of such a beast
but i don't know how to control it...I think there is no way in hal_joystick...
ah. a little different from the Logitech Wingman :)
xemet: I think it would be cool if you would follow up to the list and say what you've done
i could get it vibrate when I reach the area limit!
of course I will do it,
now that it works I will report all I've done in the mailing-list
or the wiki?
maybe both (a summary on the list, hal code on the wiki)
well...if someone tells me how to enter informations in the wiki...
never done it before
ah! I've to ask you a thing
this is instructions for creating pages
ok, I've bookmarked it
I will read
y have sucess witt slack!
i edit /etc/init.d/realtime
look at this: http://www.3dconnexion.com/products/3a1d.php
it is a low cost (55$) 3d navigator device
03cradek 07v2_1_branch * 10emc2/docs/man/man1/hal_joystick.1: backport: xemet reports /dev/input/js0 is the default on ubuntu 6.06
03cradek 07v2_1_branch * 10emc2/src/hal/user_comps/devices/hal_joystick.c: backport: xemet reports /dev/input/js0 is the default on ubuntu 6.06
any possibility of using it to move a cnc machine?
140 Megabytes free disk space for driver and plug-in installation
xemet: that's hard to guess unless you can find tech/programming information about it
I can say only that 3dconnexion are developing a driver for linux
maybe it plugs in and appears just like a joystick, or maybe it is something totally different
because the 55$ device at the moment runs only on XP and mac
friend see it:
ah...I've read about people that have patched the kernel to use this device...but this is over my capabilities
i install emc in slack!!!!!!!!!!!!!
I don't know how to patch the kernel etc...
if they release programming information or provide a library, it would be possible to write a HAL driver for it
but that's not the same as a guarantee that someone will write the driver
i instaled emc in slack nad run ok!!!!!!!!!!!!!
'"...the hours have just been flying by while I rediscover Google Earth with a level of control that is completely addictive. I need to remind myself to eat." - Stefan Geens, editor Ogle Earth Blog'
um yeah right whatever
you know about emc not runs in slack?
because in /etc/init.d/realtime
line is /sbin/fuser
owerwrite this for /usr/bin/fuser
i made package of kernel patch
and make one tutorial about install in slack
can you put it on the wiki?
well...people I'm here to learn, what is slack (i think it is a linux distribution...) and why it is better than ubuntu?
xemet: it's just a different linux distribution. Usually the reason to prefer one distribution over another is personal
xemet: if you want to use emc2, but don't feel you are able to patch a kernel, then Ubuntu is a good choice because we provide a realtime kernel that works on many systems.
yes...it is my case... :)
new HAL component candidate: deadzone. http://emergent.unpy.net/files/sandbox/deadzone.png http://emergent.unpy.net/files/sandbox/deadzone2.png
input on the bottom, output on the top
slack is good because is light
and turns in 486, mmx
the center and size of the deadzone is configurable
no in 386 because rati no in 386
no in 386 because rtai no on in 386
talk about joysticks reminded me of this, because typically an analog stick does not stay exactly at a center position, and if you're using it to control an axis you will get spurious movement if you do not implement a deadzone
I've thought that before trying
you know florianopolis?
automagically, at the center, the value reported by the hal axis pin is always 0
maybe today's analog sticks are better than the ones I'm familiar with
I bet my newest one is at least 7 years old
or maybe the driver report round the value to 0 at the center
even if it is not precisely 0
what is florianopolis?
a city in south america? http://en.wikipedia.org/wiki/Florian%C3%B3polis
03cradek 07v2_1_branch * 10emc2/debian/changelog: changes to remember
That is cool.. emc2 is so powerful.
i am is hear
I've a project...but at the moment is still at the beginning...I would like to ask you something
I would like to machine complex curves or surfaces using EMC2
like NURBS or Spline, bezer etc.
the problem is
I've tried to interpolate a NURBS using the G0
so the nurbs is interpolated using small segments
xemet: if you have lots of small segments, be sure to use G64 P- to set a path following tolerance
also be sure your axis accels are set as high as possible so the machine doesn't have to slow down to make every corner
you've centered the problem!
how long are the segments?
well...I don't know...they are variable
I would like to know if there was a way to command the movements without using G-code...
I know it could result in a very complex problem
At the moment the thing is very simple. I've programmed a small graphic interface in python
not really, there is (gcode) but it will work exactly the same as using all G1 commands in a gcode file
err there is (usrmot)
that draw curves,
now that program simply calcs the points
and at the end it send at the output the G-Code
using G01 to link the points with segments
the only problem is that the movement is not smooth
normally in emc, the realtime 'motion' module sends position commands to another component such as stepgen to control the position of the motors.
ok, let me understand the chain
one instruction is read in the program in the G-code form
you could create your own HAL component that produces position commands, and basically use only the motor control portions of emc
the interpreter translate the G-code in?
but this would require a substantial amount of programming -- you would have to do the work of generating a position every 1ms, and ensuring that the successive positions do not have greater acceleration or velocity than your machine can handle
it would also mean that the existing GUIs would not be very useful to you
well, I imagine...the problem is very complex
xemet: you said " I've tried to interpolate a NURBS using the G0" , did you mean G00 or Gxx?
At the moment I've not the programming skills needed to do a thing like that...
the problem is that when I've a lot of G01 that interpolate the curve, the max feedrate decreases
xemet: I think I interrupted you before - you never said exactly what the problem is (when using G1) that you want to solve
I think because there are a lot of accelerations and decelerations
in the emc trajectory planner, each individual segment should be long enough for the machine to go from dead stop, to the requested speed, to dead stop, within the length of the segment.
this is because emc plans each segment so that it can come to a stop exactly at the end of the segment
yes, otherwise it will go slower than requested
Well I explain the problem:
if I interpolate a circle using G01 and a lot of segments
you can reduce this length by increasing the permitted acceleration
the result is probably ok, but the max feedrate decresases and the movement is not smooth
if I use the G02, the result is ok and the feedrate is ok, and the movemente is smooth
now, what I would need...
I would need a new G-code where I specifies the curve parameters (for example control points)
just like I specify the center and radius for arc interpolation
we would accept such a feature if it was contributed, but right now nobody's working on it
that would be great
but...at the moment
I don't know what EMC2 does when it encounter a G02 code
in order to get the smooth movement
it moves in a circular/helical path - it does not split it up into straight moves
in my mind, there smallest movement is always a line...
because if I've stepper motors
even if I'm going through an arc
at each servo cycle it sets the new requested position along the circle as permitted by machine constraints and requested feed rate
I will do it step by step
i should start worrying about how i should get a cnc table somehow
For both circles and lines there are functions 'f' which give the location of the point which is a distance d into the curve: x,y,z = f(d)
so each 1ms, emc calculates how far into the current segment it is, and then gets the coordinate on the curve for that distance
how install axis interface?
wonder if i should try to build it or buy it all
(i've heard such "precision" part are pretty overpriced)
there is not a simple calculation to give the length of a spline, as there is for a line or a circular arc
that is one of the major barriers to adding spline interpolation to emc
i compiled emc, but axis no
I understand the problem
how install axis interface?
how compilel axis interface?
also the velocity and acceleration along the spline is hard to calculate/cap
so the only way I can explore is the one I'm just trying...using an external interface to generate curve points, and send G0 commands to axis
(it's not constant like for arc)
because the tangent varies ( direction )?
right -- at another step you need to find the acceleration "used up" by following the curve itself, because that lowers the available acceleration for starting and stopping
well...quite impossible for my poor mind I think :)!
I've read somewhere in interet in an article there was one of the developers of the original EMC that add a G-code for spline...
So I thinked it was possible to do a thing like that
it's definitely possible
that code was a stub, not possible, desired
(but not impossible)
howto change the polarity of xdir pin ? i can invert this signal !
apedro: to reverse the direction of an axis, make INPUT_SCALE negative in your ini
yes, nothing is impossible...but I recognize my limits! :)
it was not impossible to develop EMC2...
wish i had the gear to mess around with software
cradek thanks , it is work fine !
xemet: if i understand, it actually works right now, just slower than you'd like, not as smooth as you like
(lower you expectations :)
no, try our suggestions for improving it
but at the moment it could be ok
raise acceleration if you can, and use tolerance mode
I've to increase che max acc value?
I will try of course
now I would also try to add some functionality to the joypad...
just to experiment with HAL
how compile axis interface?
Does anyone have a clever idea on how to solve homing in an XYYZ (4 motors and drivers, 3 axes)?
for example, I could use two or three buttons to change the jog-scale value
how compile axis interface?
rafa, sorry I cannot help you...
I don't know how to do that
somebody for love of good can help-me :)
i see photos of carnival of brazil
and is hoot!!!!!!!!
axis will compile when you compile emc2, if you have all the requrements (python and friends)
how did you build emc2 w/o axis? "On August 8, 2006, AXIS became a part of emc2. There is no need for a separate CVS checkout. " http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Installing_EMC2
i download emc for sourceforge
slundell: there is some discussion of gantry homing on this page: http://sourceforge.net/tracker/index.php?func=detail&aid=1075625&group_id=6744&atid=356744
and in sources no axis
you cvs or download?
in 2.1 witt axis?
there wasn't much (any?) response to my proposal, so the only thing in 2.1 is the homing sequence, not gantry kinematics or the homing extensions proposed.
yes, i think so
but i compiled
i have unistall 2.0.5 and install 2.1
* jepler goes to lunch
no necessary unistall 2.0.5 for install 2.1?
1st you can make a new emc2 without disturbing other emc's on your computer
so dont worry about old stuff
do you want to try this: build and use emc2.1 in a new directory?
how to set a pin status with the joystick button?
jepler: Is there any documentation on this homing sequence? I am currently copy-pasting dallurs config (i.e. connecting the same step/dir signals to multiple pins).
The button has a false state when released, and a true state when I press it
So, if I want for example use a button to command the spindle on and off
unfortunately, I don't think there's a spindle toggle input anywhere, though Halui could have one
you may want to look at halui - it's meant for interfacing buttons and things to EMC functions
ok, lets go the spindle
take for example flood
again, I'm not sure there is a "toggle" input for that
there are separate "coolant-on" and "coolant-off" inputs
I see in the manual there is a pin iocontrol.0.coolant-flood
that's an output
TRUE when flood coolant is requested
but...how are they controlled by Axis?
ok - you may be able to use a flipflop to get what you want
M<something> turns coolant on or off
ok, I don't know what is a flipflop... :)
sorry...I'm still learning everything
hmm. that won't work alone
you will need to use halui, so I'd take a look at what it provides
you don't want to directly connect spindle or coolant to your joypad, since you'll want emc to be able to control them as well
so you need some way of telling emc what to do when you use the joypad. halui is the way to do that
I would like to have some buttons in the joypad that act just like the buttons in Axis interface
that's what halui is for
how to use it?
you add HALUI=halui to the ini file. I don't remember which section
you add HALUI=halui to the ini file. I don't remember which section
sorry, it was disconnected
after I add Halui...
yuo'll have about 100 more HAL pins to play with :)
I add HALUI=halui in the HAL section?
it's either in HAL or DISPLAY - I'm not sure which
ok found it in the wiki!
so I just add it in the .ini
And i can use the new pins in the .hal joypad file
I bet there's an example in one of the configs. I don't know which one(s) though :)
well I will find it don't worry
another idea...but now I think it is more complex
If I want for example use two buttons to set the jog scale...
think, for example: I press the button A and the scale gets set to 0.1
press the button B and the scale is set to 0.01
dbl click it to chg scale by 10 , modifier dbl click it to chg by 1/10
I don't know what provisions halui has for that, but that's pretty easy to do with some HAL components
tomp, this is a joystick, not a mouse
you can dbl clk any btn
I don't think there is a double-click event
what modules could I use for that?
do you have an idea?
so I will study them later...
flipflop + not + mux
there may be an easier way though :)
basically I would need a module that receive a True status and set a parameter to a value
what you'd probably do is use a selector (mux) that has the two scales set as parameters, then set up a flipflop and a not as a toggle, and run the output to halui
but this conversation tells me that a simpler way should be implemented :)
I will try...I don't know what is the flipflop and the mux...bu I will search for them
are there documentations about these modules?
if you try "loadrt flipflop" and / or "loadrt mux2", you'll see the pins they provide
there should be
try man flipflop
found but... there are only the pins
[18:21:59] <tomp> http://en.wikipedia.org/wiki/Flip-flop_(electronics)
scroll down to d flops
hmm, not classic dflop with set & reset is it?, look more at jk flop
ok...maybe I understand something
it's a S/R flipflop, actually
but no /Q output
I have data in true
I do not really understand unitl I will try it...
you need to look over the halui documentation - it will be more complex doing this in HAL
you should also know that there are certain ways that emc works that may seem strange
for example, there is no provision for having a switch that directly controls coolant (or spindle ...)
yes I see
you can only ask that coolant be turned on or off, but not set the state directly
in general, toggle switches (pressing the same button to turn something on or off, depending on its state) are not a good idea
two reasons: first is noise - what happens if you get several toggles when you press the button, due to noise
yes infact I see in halui there is always a On pin and a Off pin
second: what if something else turns the spindle off just as you're about to do that? you toggle it back on, which is unexpected
yep - I was noticing that as well
SWPadnos: that's kind of odd..
so you can just have a spindle on and separate spindle off button
ok that's not a problem...
commercial controls do have a coolant button.. that always works..
I've ten buttons in the joypad and I will try o use all of them!
even if you are running a part on full auto..
anonimasu, you can have a coolant button, but there should be separate "on" and "off" buttons
a single momentary switch can cause problems due to noise (among other things)
yeah, but you need debounced switches..
SWPadnos: well, I can just imagine the panel for a machine doing that..
that btn may be hdwr, and not in software ( it may report what it did, but control is hardware, hardwire ) ( on off can be done with 1 puspush btn )
for spindle I can understand it.
yeah - coolant is less dangerous :)
the one at work forces you to select a direction for the spindle..
then push the on button..
a single button that toggles is fine in many cases, but you have to know that you may get unexpected results sometimes
otherwise the spindle wont start
"on the count of 3, turn your key to the right" :)
it's hard to turn on the spindle unintentionally as it should be :)
so in the flip flop...there are only five pins, anyone could explain me what they do?
clock, rising edge writes data to out
set, when true, force out true
reset when true, force out false; overrides set
any time you write a 1 to "reset", the output will be 0. if reset is not 1 and set is 1, then the output will be 1. if both set and reset are 0, then the output will be set to whatever "data" is whenever clock changes from 0 to 1
on the wikipedia page, a nice timing diagram and state diagram
it's pretty easy to follow how it works from the source: http://cvs.linuxcnc.org/cvs/emc2/src/hal/components/flipflop.comp?rev=1.2
but how can this help me to select a scale value using a button?
mux2 has two float inputs and one output. there's also a bit input that decides which of the two inputs to output
and you need a not on the output of the flipflop, which you run back into the data input. that way, whenever you clock the flipflop, it changes state
the output also goes to the mux2
and selects one of the scales
I begin to understand... :)
but I think I've to try it...
basically the problem is that the button has not a fixed state
play - you can't hurt anything unless you have a machine attached ;)
I press it and it became true, it sets the scale, now I release it, but the scale must remain the one selected
flipflop should only respond to the press, not the release (unless there's noise)
AH! hese was the missing point :)
changes on rising edge, ignore level, ignores falling edge
many thanks, I think now is more clear in my mind
great. have fun :)
now I go
thank you all people!
your advices are always precious
the sr fllipflop http://commons.wikimedia.org/wiki/Image:SR_%28Clocked%29_Flip-flop_Diagram.svg
I will let you know my results with this 5$ joypad!
see you, thanks
asian flipflop http://en.wikipedia.org/wiki/Image:Flipflops.jpg
you know - very high res monitors are very cool: http://www.cncgear.com/images/bigscreenshot.png
the "large text" is actually normal size (about 12 point) on the high-res monitor
* jepler is surprised to see that most of the hits for this search term are related to basketball: arc three-point convert
yeah, if those "large" are actually "normal", then what are those "normal" actually?
03jepler 07TRUNK * 10emc2/src/hal/components/deadzone.comp: new component: deadzone
03jepler 07TRUNK * 10emc2/src/hal/components/deadzone.comp: GPL license
03jepler 07TRUNK * 10emc2/src/hal/components/tristate_float.comp: new component: trisatte_float
03jepler 07TRUNK * 10emc2/src/hal/components/tristate_float.comp: oops, fix it to compile
03jepler 07TRUNK * 10emc2/debian/changelog: new items
the gcode coordenates is expressed on mm or inch ?
X1.0 is 1 mm or 1 inch ?
apedro: specify G21 to use mm, or G20 to use inch
jepler ok i have understand, thanks !
if i have run-in-place, and want to experiment with hal, then do i use scripts/halrun -I ? (i've always used individual bin/halcmd blah commands for every step, this halrun sounds convenient)
yes, halrun works with run-in-place
thanks, it's nice , less opportunities for me to spell wrong
its got tab completion too
yeah - halcmd is quite nice these days, with completion and stuff
up-arrow as well, I believe
it's not my fault. japler did it :)
jepler, that is
the secondary posision offer on the house was signed... so far so good. :)
tomp crosses fingers, good luck
re halcmd, i can put cmds into a file like myfile.ini, the exec halrun -I -f myfile.ini and all the btns and lights respond immediately... and i have interactive halcmd too, next how to get a gui on top of that (fun! sanook di! )
actually, you'd put commands into a .hal file (which is run by halrun). the ini file is there in case you want to put constructs like pid.0.PGain=[AXIS_0]P
but comands in the [HAL] section of the ini file won't get executed ...
ok, so ren myfile.ini to myfile.hal then issue halrun -I -f myfile.hal ( i had no sections in the 'ini' file, just a text file http://pastebin.ca/352431
like a script/ bat file
well, you may want both a .hal file and an ini file, but in this case, you just use -f (I guess - I'm not looking at halrun)
i think i messed up by saying it was an ini, its just a file, i need to read on what ini and hal are intended for
the ini flag is only needed by halcmd so it can look up values from the ini file
if you aren't using an ini, then don't worry about it
sigh .. eBay .. why do I always get carried away ...
robin_sz: uh oh
I start off with a sensible idea about what I want to pay and then ...
robin_sz: did you get thoose servos?
Just this once .. here's the log: http://www.linuxcnc.org/irc/irc.freenode.net:6667/emc/2007-02-12.txt
yeah .... but had to pay loads and loads ...
still, they do come with matching gearboxes
how much is loads?
I suppose that makes it not *too* bad ...
that's not a figure..
sigh ,... well, it was close to 50 eur
no more beer for this month
[21:14:30] <anonimasu> http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=320078627767
robin_sz: well, that's almost free
I expect the new price is a *bit* more than that
make sure they wipe the uk off of them before they're put in the mail
I'll collect, its like 30km from here
"wipe the UK off of them"?
Anastasia is now known as K`zan
jepler, no, i didnt undrstand that either ...
haha "the early enc28j60 parts needed the spi interface to be run at 8meg at least, because
the designers had one hand inside their pants when they designed them and managed to score
a 14-chapter errata."
wow, blogger, tell us what you really think of this part
i wrote a module that approximates **2D** nurbs with arcs...anyone interested?
for emc, i mean
linear slide pot input device, very designer high tech i saw something like this on a new logitech keyboard, looked like Bang&Olefsun designed it http://www.qprox.com/products/qslide_qt411.php
wow ... now ... I'm impressed. I've seen some really evil bastard marketing schemes, but the Solidworks one is so evil it has horns ....
maddash: sorry i missed that, of course we're interested, sometimes we are away. i think we need a way to handle these news flashes that occur while gone.
their big competitor is Autocad, so they have made a drawign viewer, a plugin that allows your current old version of autocad to load even the very latest version of autocad files (no need to upgrade autocad anymore) and a autocad lookalike CAD package
and then ..
they give them away for free
talk about chopping the competition off at the knees
I mean, the only reason you ever upgrade autocad is because people keep mailing you files in averison you cant open
with an "open anything" plugin, that kills their slaes model
well it's not like autocad can compare anyway..
so by giving a really good 2d package away fro free, they dont even harm their own market
its nto like autocad can fight back by releasing a free 3D solidworks lookalike is it?
evil bastards ..
I like it :)
if thoose bastards just got a good snap.
and a sane way to enter lengths on line creation
oh, there is ...
I really need to figure out how to install acad13 here, forgotten how and I really do not want to have to make up 23 floppies, not sure I even have that many anymore :-).
if you commence a dimension after creation..
or ente rit numerically
that you need to do every time.
you can snap it to a point
open the window for it..
I rarley define line lenghts anyway
so its not a big deal for me
hm, how do you actually draw real things?
well, that's a pain in the ass haing to add a dimension for all lines after you've created them..
thats the point
well, you cant be drawing anything that needs to match the real world..
no ... I think you havent understood solidworks :)
let me give you an example ...
FOR FUCKS SAKE IM NOT TALKING ABOUT SOLIDWORKS
oh, well then I cant help
I'm talking about alibre.
never seen/tried it
it's a damn good solidworks competitor, that's 1/5 of the price..
parametric, but it's a bit more painful to work with.
they have a free version that just limits the parts in a assembly..
but, as I said, adding dimensions in it is a bit of a pain..
so .. how does their dimensioning differ from SW then?
but creating lines with a specific length needs some more work.. a few clicks..
as I said, its not that often yo need to do that
you need something to relate to.
yeah, usually some base dimension ..
let me give you an example ...
and I dont know where you are pulling that out without something to measure aginst..(construction lines..)
robin_sz: you dont have to..
but I want to :)
I designed a bullet-proof door last week ...
there is a sketch for the wall opening size, a rectangle with two dimensiosn added
there is probably ... what, 10 maybe dimensions added in total to the rest of the 20 or so parts that go to make up the rest of the door
I know how that works, but it's not as nice as solidworks.. :D
that was solidowrks btw
yeah, I know
alibre does the same..
the customer was VERY impressed by the way I produced a set of flat-pattern drawings for the laser from the parts
and then just changed the base rectangle size and the whole desing chnaged in an instant to match it
they *lurv* that
I did notice a REALLY bad solidowrks fsck up the other day though ...
you have an assembly open with a part called 'foo' ...
and someoen asks you to look at another desing ...
and that has a part called foo.
and it seems to be able to tell the difference ...
I'd punch them in the face, and when they would have recovered I'd punch them again.
but when the parts are on a network drive, it seems to get confused
and then you sudenly find weird bits appearing in the other model ...
at which point, I think what you suggested sounds a good idea :)
only idiots name their parts foo
well, not foo then
I usually name mind as NAME(manufacturer number)
if working with real models motors/sensors and stuff...
I usally add partnumbers as a property
so I can just look at the assembly or print it when ordering stuff..
so it shows up in the drawing
I wonder if there is a solidworks irc channel?
if you find one tell me
it *would* be useful to be able to ask questions
I used to use the SW forums, but they are very heavily censored I found
even worse than #debian ;)