anyone have recommendations for a CNC shop in the midwest to mill some 6063 flat stock?
i'm not midwest, but i can do it
1-100 x 19 different parts
+/- 0.0015 tolerance stuff, pretty basic but having trouble finding a decent shop
tollerance shouldnt be an issue
largest piece is ~2" x 8" x .25", some are only ~1"x1" x.25"
oh not a problem at all
yesh, am getting crazy high bids
don't they knew we're in a recession
they're trying to pay the rent with 1 job
if you want, shoot me a print and i'll quote it for you
are you supplying material or am i?
actually quoted me $315 for a rectangle ~1"x1" x.25"
maybe they think 6063 is gold
how many pieces was that quote for?
maybe, I can supply the stock, it's all made from .125, .250 and .500 flat stock
the 10 piece was ~110
$300 is what, 6 hours at $50/hour
not sure, I can even generate the CAM files
maybe they were going to make them all by hand
I can see it taking quite a few hours for the first one, when you consider all the little stuff like paperwork, programming, fixturing, shipping, etc
I could file a piece by hand in under 6 hrs
not when it's 19 different pieces at 10- 100 per month for each
surprised with the midwest, lots of shops just didn't bid
I'm just saying that the first piece is always gonna be expensive because of overhead
must have old machines since they whinned about +/- 0.0015, they wanted to be sure it's not 0.015 we need :) heh
i have very little overhead because i'm a small shop, so it just makes my jaw drop at some of the quotes my customers have been getting
have a website?
.0015" isnt hard to hold
yes, I know, I build machines
it's not up yet, i've been too busy (thankfully)
we're just not a shop, we're a lab
i build machinery as well
but for manufacturing
L84Supper: what do the parts look like?
just profile mill the outside? or drill holes? tapped holes? how many setups would be needed, etc?
here's my email if you want to send a print or model: email@example.com
milled sides, with some tapered areas + M3 holes and taps
like, tapered end mills? or 5-axis work?
3-axis movement is all that required
5 axis i cannot do
can you view iges?
any format will do, i have solidworks
I'll send some iges in a sec
have native for that as well, we run just about everything but heeks so far
as long as it's 2008 or older, or you backsave it, that will work
you have mail
what exactly do you need a .0015" tollerance on?
and is it +-.0015 or +-.00075?
the parts all fit together with slots and the distance between them is critical
Jim is now known as Guest79364
I'll send you a jpg of the assemblies
that will help
you have more mail
anybody involed in hm stepgen.c?
so you're making 10-100 of these assemblies a month?
not yet, but will be soon
dan1mal : going to private
woo hoo - fixed my 25 year old microwave
should be good for another 25 now ;-)
jmkasunich: replaced the relay, huh?
w00t got my spindle working, thanks to you guys
you did all the work
Why EMC2 do not support DSL (Damn Small Linux)
is it because the downward kernel?
Damn small EMC2 is sound nice...
is anybody here using brl-cad? is it usable?
Spida: it's certainly usable, but personally I found it has a too long learning curve
you can check out #brlcad for specific questions though
it's been deeloped for more than 25 years now, so it should be quite capable ;)
alex_joni: So has Man kind, that's not saying very much.
mankind is quite capable :P
btw, seen google wave?
alex_joni: Interesting. I can't fnish it all tonight, but I'll look at the rest tomorrow.
I found it interesting to watch
alex_joni: what are you using?
Spida: depends ;)
on what I need to do
if it's only CAD work, or I need CAM afterwards, etc
at work I use Alibre for 3D (CAD and very seldom CAM)
for 2D I use various freewares + sheetcam as CAM
Alibre is payware, isn
they have a free (limited) version
but I have the pay version
alex_joni: is there a description of the free version somewhere? I just found that its like the professional for the first 30days, and then downgrades to some unspecified xpress version...
there was, but they changed the website lately, so I'm not sure
is gcam (http://gcam.js.cx/index.php/Main_Page)
the writer was a dev on brlcad for a while
Spida: it limits the assembly size..
five unique parts
and no 2d drawings
and no boolean operations..
adn no lofting/shelling/helix/sweep
but well, you can live without thoose..
I have the expert version and, they arent the most critical
for most stuff
no joining of solid parts..
though, if you depend on thoose to make your parts(unless you make mold cavities, then you are a fossil, leftover from a 3d program..
no, certainly no fossil, I just started thinking aboud cad/cam/...
I did some electro-cad with eagle, and some parts from the brl-cad tutorial...
but thats it.
alibre is very much like solidworks
so just to see if I have understood correctly: the workflow would be to design some part in brl-cad, use gcam to get toolpaths, and execute it with emc on some hardware?
brl-cad seem insanely hard to learn
anonimasu: in what respect? using the command window?
that is when I don't get my line-up pins right ;)
I need to get motivated. time to get back to the garage work.
* archivist hands a cup of motivation to skunkworks
haha I think you might have the board rotated a bit...
I drilled the line up pins by hand ;)
I am almost done with my first cup of motivation
I think it may take 2.5 or more
I need some of that too
I still haven't fixed rotated non-xy arc previews
Spida: in respect to being clunky like they are still back where cad programs were maybe 10 years ago..
It took me a second to figure out the specifics.. I thought it was a new gcode - not an extention of g10. (the systems.ngc didn't have the coordinate systems set)
as you can see from mdi ;)
systems.ngc was a learning aid for AXIS's touch off
but there is no rotation equivalent (how should it work?)
ah - I just reconized if from your computer at the fest :)
hmm - good point. It will work as is.. It is similar on how I set the tool length at first (changing g10) but that causes issues with preview as it doesn't get changed at runtime. (you have to re-load the program)
unlike tool length setting like you do in the eagle ulp
I don't know if I am making sense this early in the morning
Can somebody help me to get the [AXIS_N]HOME and HOME_OFFSET parameters to hal pins?
JanVanGilsen: home and home offset are in nml, so the shortest route to having them in hal pins is probably to add them to halui
JanVanGilsen: are you trying to change those values on the fly?
er, maybe I'm mistaken -- I was looking at class EMC_AXIS_SET_HOMING_PARAMS which is to set them, not to show them
JanVanGilsen: can you back up and say what problem you are trying to solve?
I take it back, I don't think they can be read through stat
yes, my puma arm has a potentiometer on each joint giving a aproximation of the absolute position
jmkasunich: did your table make it to you?
JanVanGilsen: so what are you trying to achieve? you want to use the pot + index to home without actually going all the way to a home switch?
there is no home switch :)
is there an index?
the aproximate position will be rounded down to get te "real" position of the next index pulse
hmm - nice..
JanVanGilsen: did you end up replacing the encoders then?
no they work fine :)
they have an index also?
huh - I need to look at mine. interesting
interesting idea - look at pot - figure out where the arm is and where the next index should be then.
if you want, i can copy the pinout of my encoders :)
JanVanGilsen: you are in slightly unexplored territory
The goal is to prevent unpredictable moves during the homing process
the "right" way to home your machine would involve changing the actual homing code in EMC, but that isn't simple to do
tweaking the homing parameters so that EMC thinks it is running its normal homing process could work
Then i only have to write a hal component that desides where the next index pulse would be
are they ttl? - I thought they output a 'sinewave' greycode that would have to be run thru a comparator.
(assuming we have similar arms)
In my controller, the encoder signals are connected to a shmitt-triger/inverter witch outputs ttl levels
ah - ok. We didn't get any of the control.
skunkworks: yours is a Puma, maybe JanVanGilsen has a puma (IOW, puma is a generic description of the arm geometry, not the brand name)
My arm is a real Unimation Puma robot :)
i'll check build date :)
ok, then probalby you and skunkworks have the same thing (more or less)
JanVanGilsen: I assume you've read http://www.linuxcnc.org/docview/html//config_ini_homing.html
26 JUN 1985
you basically want to do index only homing, but with HOME_OFFSET (and possibly HOME) set after reading the potientometer. is that correct?
Yes i did read it.
I wish we had made a giant leap and used HAL params (or pins) for all motion controller config items
since we didn't, I think you will have to write some C or C++ to solve your problem
yes, I think sending a EMC_AXIS_SET_HOMING_PARAMS nml message will modify HOME_OFFSET and HOME
that message isn't exposed in python, so your other choice is C++
or to expose it in python
does that message have a way to modify _only_ those params? or will the sender need to know the existing values of all the other params?
could this be done from a Hal component?
JanVanGilsen: it would have to be a user-space hal component
the other approach would be to hack the motion controller to get HOME_OFFSET from a hal pin
I don't know which approach is more perverse
skunkworks: My robot came with a giant pile of "electrical and mechanical drawings"
wow - you would be able to home it a ton more accurite than it ever did in the original controller. It only used the pot voltage.
it had an index pulse but didn't use it? that seems dumb
I got most of the manuals... I will have to see if i have some of the encoder schematics.
My countroller does use the index
hmm - interesting. either I missed it in my manual - or mine didn't.
I would think former. ;)
ok, lets talk about exactly how to do this in EMC2 (I'm a bit pressed for time, I have errands to do)
you want to read the pot (I assume you have some A/D converter, and a hal driver for it)
you want to compute the position of the nearest index pulse from that A/D reading
you want to set that position as HOME_OFFSET
you must either do this constantly except when homing is actually in progress, or you must do it once just as homing starts
there is also an ambiguous area - if you happen to be very very close to an index pulse when you start homing, the analog value might tell you the location of the index pulse that you are 0.0001 rev away from, or the one that you are 1.0001 rev away from
with regular index homing, you make your home switch (or marks on the table, if doing index-only homing) about 0.5 revs away from the index to avoid that
how do you intend to address the ambiguity problem?
if the potentiometer is read when the joint is at the index, this shouldn't be a problem.
so you want to read the pot and generate the HOME_OFFSET value just as the index is reached?
that rules out sending NML messages to set HOME_OFFSET
since NML messages can only be sent from user space (non-realtime) code
if you need to read the pot at a specific instant, it needs to be realtime
so a hal pin would be best?
do you know C?
couldn't you read the pot while not moving? calculate where the next index pulse should be - set the home offset and then home?
Not wel, I understand it a bit :)
not if you close to the index pulse
because of the ambiguity problem, you must either "read just after detecting the index", or "read well before detecting the index", and the latter is impossible if you are already very close
the homing code is a state machine
you can probably follow it by reading the comments
for index only homing, it starts at line 581
you will want to read the pot just as it transitions from HOME_INDEX_SEARCH_WAIT to HOME_SET_INDEX_POSITION
unfortunately that is impossible
since that transition takes place entirely within the motion controller, no other code gets a chance to run between those states
the only solution I see is to have a hal component that is always reading the pot, and always calculating the offset
That wouldn't be verry hard..
and to add code to the motion controller right before line 661, that will read a newly added HAL pin to get the home offset
you would also want to read that newly added pin just before line 606
I would also need to set the HOME parameter to be the same as home_offset, else the joint will move to home at the end of the homing
that would be at line 690
oh, wait, that won't work
I think the kinematics code will be unhappy if you go randomly changing home
is it important that you not move (much) when homing?
there is some logic in the motion controller, especially for non-trivial kinematics, that requires all joints to be homed or "at home" before you can change to coordinated mode, etc
the logic is complex, and I'm not sure what cases require you to be "at home" vs simply "homed"
Yes, robots usually have a lot of stuff in their work area, uncontrolled moves like that are dangerous
jmkasunich: I think the code requires to be homed
for kinematics BOTH you can switch to joint mode, move some joints, then switch back to world
(at least it worked at one point that way ;)
alex_joni I think it depends on whether you have kins BOTH or INVERSE_ONLY
and I don't know which one pumakins has
it has both iirc
and too lazy/rushed to look
ok, that might make things better
but whoever needs to use it will probably have to work it out ;)
but I'd still be worried about changing joint->home on the fly, without fully understanding the implications
one way to avoid the final move would simply be to skip it
change line 667 so it doesn't switch to state HOM_FINAL_MOVE_START, instead goes direct to HOME_FINISHED
and also change HOME_FINISHED - line 736 needs to say AT_HOME_FLAG(joint,0) since you aren't neccessarily at the home position
If I'm not going to write something that is going to be committed, i could just replace joint->home with joint->home_offset
you mean at line 690?
that would work, but you'll still need to change line 736, since you won't be AT_HOME when you finish
anyway, those are details - it sounds like you are managing to understand the homing code, is that correct?
the other changes you'll need to make are to create a new pin (or pins), I can try to show you where that stuff is
then I have to go away for a while
Yes but not how i need to get the hal pin into it
[15:47:26] <jmkasunich> http://cvs.linuxcnc.org/cgi-bin/cvsweb.cgi/emc2/src/emc/motion/mot_priv.h?annotate=1.78
this file is where hal pin/params are declared
i think it would be best to make something that could be comitted...
that will be much more complex - what works for you will break other people's machines
something that works for you _and_ for other people is a lot harder to figure out
and I certainly can't spend that much time today
lets focus on "how to add a new hal pin to the motion controller" right now, OK?
are you looking at http://cvs.linuxcnc.org/cgi-bin/cvsweb.cgi/emc2/src/emc/motion/mot_priv.h?annotate=1.78
the structure starting at line 34 has all pins (and params) associated with a single joint
around line 75, you'd add "hal_float_t *home_offset; /* WPI */"
Yes, that's clear
that gives you a memory location for the pin, but doesn't make it visible in hal
the block from line 676 thru line 680 exports the jog-scale pin
you'd want to duplicate that for your new pin
changing the name in line 676, and the variable name in line 677
that exports the pin to HAL
JanVanGilsen: follow so far?
I'm trying to figure the best way to read the pin
[15:56:34] <jmkasunich> http://cvs.linuxcnc.org/cgi-bin/cvsweb.cgi/emc2/src/emc/motion/control.c?annotate=1.153
most joint-related hal pins are read starting at line 492 in that file
but if you do it there, joint->home_offset will continue to change as the machine runs after homing
I'm pretty sure you don't want that
the actual read from HAL to the joint structure will look something like line 503 or 504
you'll probably want to do that in the actual homing code, as we discussed earlier (homing.c)
i don't think thats a problem, the offset should be changed if i home the joint a second time...
yes, if you home a second time
but not every time you move the arm one motor revolution
process_inputs() runs every servo period
so i'll need to acces &(emcmot_hal_data->joint[joint_num]) in the homing.c
I would copy line 367 of control.c into homing.c
then copy line 495 of control.c into homing.c
then you can use joint->home_offset = *(joint_data->home_offset); at line 661 of homing.c
I have to go now - it sounds like you have a good idea of what to do. I will be back later, or someone else can help if you run into problems
ok, that seems to cover it all :)
Thank you verry much =)
maybe we should think about making all those things into HAL pins for version 2.4....
this onboard video card requires xorg-server 1.6 or greater, and it's saying I have 188.8.131.52, how hard is this going to be to upgrade?
any of you use jaunty and emc?
[16:57:48] <bglackin> http://www.doughtydrive.com/machine%20demo.html
nice little 5 axisa
Kirk - Some video with 0 backlash A and B/C axes. NOt allot of info on how he does it (except for the order form...
[17:04:32] <bglackin> http://www.doughtydrive.com/download.html
this onboard intel video card sucks
Hello, I have been playing with IRC "/" commands, I hope I didn't cause any trouble.
Hi Kirk, no problem, you just rebooted my system
Any IRC short cuts that would be handy?
what do you use to talk IRC? I use Konversation and don't see a need for playing with commands much
I use xchat and its up 24/7
I found "/help", but it didn't reveal much. I use Mibbit.com.
proxy services are not so good
and liable to get banned to to bad users
tried man irc?
I'll check Konversation, xchat
kirk_wallace: try irssi, if you like terminals
I use KDE all the time and that's why I use Konversation. Allows for diff identities for different channels, I like this feature
I did notice a tip saying "don't type in / commands that other people tell you to enter, unless you know what the command does.
that's always a god advice. OR you could be advised to "rm -rf /etc" as root but that's for other less advanced channels
Sometimes the conversation can go pretty quickly, so I thought there may be some short cuts. I guess there is no real magic involved.
notranc: So you can get to someone's shell through IRC?
well, I was joking but just like any other streaming connection to the net makes it possible for security issues
getting into someones shell would be a very bad security problem,
Oops, not thinking, you have to advise the person to open a terminal, dooh. The / commands can do damage though?
you can exchange files between the users and that makes it possible to bring in virus. We are talking about Windows mostly. However, if one were to download a shell script that would change /bin/passwd for example, you can imagine what that could do to your system
I looked at the Dourty drive videos. My guess is that they are a two set belt drive. Fine for routers, but I don't know about a mill.
yup ok for wood and plastic
that site needs some work or it's designed for NotFirefox browser. I could not see all things properly.
he has a link to http://www.cnc-toolkit.com
which has more interesting stuff
What should I know about IRC Topic?
it what way?
I see it mentioned, but I don't know how it would affect anything I do.
topic is for new users to a chan
some chans point to rules
Oh so it could be like a README.
this is EMC channel so I expect related stuff. Off topic sometimes boring away. I've seen some very funny links from people on this chan.
s/Off topic sometimes boring away/Off topic sometimes takes boring away/g
some chans we have to control off topic
Is this the topic - "Welcome! EMC (Enhanced Machine Controller) is a linux-based ope... "
I believe so Kirk
Well, I've had my coffee, now I have a tool changer to fix. Thanks for the info. Ciao.
anybody at or going to http://makerfaire.com/?
There were CNC and laser machines last year. I expect the same this year.
where is it?
San Mateo CA
lol not me
whos paying my air fare?
Ask for stimulus package
I'm in IN, that's to far
There is a chain of Maker Faire so you might find one closer to your home.
heh Im in the UK
archivist, hop on Virgin and you'll make it for tomorrow?
I'm poor and unemployed atm anyway
I would rather spend the moneys on hardware over here, Im nearly unemployed
maker faire is very interesting place where you might get ideas for getting out of poverty in case the Prez won't do it for you
I'm unemployed too.
I'm going to school, that will get me a job hopefully
tlab, that's good. Need to learn all your life.
I enjoy it
that's the idea.
1.5 years left and I'll have my BS degree
in Electrical Computer Engineering Technology
boss is selling the site here. so I become unemployed but can take a few toys home http://www.archivist.info/cnc/works2008/
that's very good.
better than unemployed without tools
ya you could be like me, ten years at chrysler and nothing to show pretty much
only a little, one needs capital to advertise and get work in
my first 4-5 years at chrysler, everything I worked on dated from ww2
* roh learned that advertising only gets one the kind of massmarket customers which is pain and no gain. better specialize and be know for what special thing you can do and get jobs via people who know what youre good at.
advertizing is cheap. Websites etc. Just need to find niche and sell it worldwide.
the out of spec column on parts would be full of numbers
tlab, we have a 1910 ish machine here
probably makes better parts that what we used lol
I noticed that some machines were not up to safety standards :-)
just need to add stepper, safety guards, and EMC and you have a modern CNC machine.
[18:10:23] <archivist> http://www.collection.archivist.info/searchv10.php?srcdata=title&srcprog=searchv10.php&searchv4page=1&errlev=0&searchstr=garvin
saftey gaurds :P
we dont want no safety here
you normally spend half a day removing the saftey crap from commercial machines just to make them usefull
we machined transmission cases for chrysler
I knew a guy that said a case landed at his feet, came from 10-15 feet away
chipped the concrete
i once managed to make a big corea mill throw about 2-300kg of tooling block through the saftey doors
that was fun
imagine a transfer bar pulling 20-30 pallets with cases, stopping at a station after each pull
I had a saw throw parts of my bench many feet away at someone else
you guys are dangerous. I have to put up digital shield.
I came back from break, found 4-5 pallets on the floor at the robot, each pallet is probably 500lbs+
lol thats not that dangerous
trying to start a jet engine with a broom stick and a can of propane in a saudi desert
now thats dangerous
that's beacuse robot protested you did not take him with you for a break
broom stick? no metal stick?
colin_: Any luck with the kinematics?
robot was stopped, transfer kept pushing pallets on the floor
geo01005, iv had a little look at them
im just trying to work on a vismach model
i take it i need one without an A3 offset ?
or kinematics for your bigger arm?
i was just going to convert existing cad files from the ABB site into vismach objects for speed
but they have A3 offsets
Well the Js-10 dosn't have an A3 offset, so yeah it would need to be changed in vismach.
It looks like the kinematics for the ABB robots are easier than the puma kins.
the only difference is the offset on the base
its forward of center instead of to the side
would it be stupid to try and install emc on jaunty?
There is no left or right position, every joint in the bot lines on a plane.
yup to me?
I also think that I have never seen a ABB bot like that with the "elbow" below the "hand"
so there is only one solution.
rather than 12 or 16 or whatever it is with a puma bot.
we had several of these bots at chrysler http://www.nachi-fujikoshi.co.jp/eng/rob/hand/index.html
the arms normally come from above
i think they do different types of bot for shelf mounting ect
Yes, but at leas the robot that you showed the picture of is that way.
And I believe that any of them with a four bar mechanism on the back with be the same way.
Anyhow, good luck with the vismach model.
JanVanGilsen: the idea you present is like heidenhain's 'distance coded' scales. there's many reference marks along the scale, homing is never more than 2cm motion.
I'm half tempted to try emc on jaunty
i'm (constantly) trying to setup a slave-master installation (aka remote gui) with emc2-trunk and nml (i am unable to use x window forwarding or vnc because of my hardware)
i'm not sure how to setup the ini file on the master (gui) side.
if possible i want to use axis instead of tkemc
tlab: to use EMC (for real, controlling a machine), you need a realtime kernel
we have such kernels already built for dapper and hardy
for jaunty, you get to build it yourself - which is neither easy nor fun
ya, can't I recompile for jaunty with rtai?
you would have to compile a kernel for jaunty, with the rtai patches
_then_ you compile emc for that kernel
recompiling emc is the easy part
I've been recompiling kernels for a week now trying to get everything right, and manually install rtai and emc
I just don't know it it will all work on jaunty
if the rtai kernel works (big if), then EMC should work
but you are on your own when it comes to compiling the rtai kernel
well I don't even have hardware yet, so I guess it wouldn't hurt to try it
whatever floats your boat
was just wondering if anyone had done it
personally I'm thrilled that I've never had to compile a rtai kernel (been working on EMC for 5 years now...)
I like to piddle with stuff, it's my downfall
i love the fact emc comes on a live cd
couldnt make it any easier to setup an emc machine
I'm bad about wanting the newest and fastest
is that really important for an emc installation ?
reliability surley is more important
sometimes newer is more reliable
besides hardy hates my video card
upto you if you want to do it
I can always reinstall everything
tlab get a cheap radeon7000 or 9000 without fan (passive cooling)
reliable, cheap and supported by good and free drivers.
all I have is 1 pci slot
newest is not best for machine control
tom3p: it would be wonderfull if somebody with coding experiance could figure out a way to incorperate such a homing sequence
a pdf on installing rtai on various ubuntus http://www.pdf-search-engine.com/guia-kubuntu-pdf.htmll
there is a reason they call it the bleeding edge
tlab uh.. slow box? grab a matrox
G450 or so
it's a new intel atom 330
dual core, so I had to add that support
tlab: somebody has built an rtai smp kernel for the atom
JanVanGilsen: jmkasunich outlined the sequence needed, and yes it requires skills that i've not practiced in years ;)
ya, but it doesn't work with the video card worth a crap
I've tried that kernel, running it now.. even modified for it
what video card? you mean the onboard video?
I've run that kernel, it works fine
tlab uh.. i see.. so its onboard intel graphics?
they are quite ok usually.. but yes.. hardy could be too old
I jumped to a conclusion - I have the intel D945GCLF2 mobo with atom 330, and the hardy + rtai + SMP kernel works fine
maybe tlab has a different mobo with the atom chip
JanVanGilsen: it requires an encoder with many 'Z' over the trvael, so rotary encoders and distance coded encoders are candidates
jmkasunich: what are your latency tests?
how about glxgears ?
it's been a couple months since I played with it, I think it was about 15uS
thats the same mobo I have
the wiki shows 6-7k
I think the wiki is a bit optimistic
well part of it could be SMI http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?FixingSMIIssues
but I dunno
but 15uS is still pretty good
we use 18 usec since 16 were too les
but SMI off can cause overheating
[18:52:48] <tlab> http://intellinuxgraphics.org/index.html
has newer video drivers but require newer version of X
I could imagine a cnc with some scale along the axis so the offset should be entered by hand, or an gray-code encoder to get an absolute position
some kind of incacurate way to estimate the next encoder position :)
JanVanGilsen: I've thought about that too
would be nice for lathes, where you can't neccessarily go all the way to the headstock (hit chuck) or the other end (hit tailstock)
Heh.... micro GPS modules on all joints and use them for positionng =)
cubecorners on each joint with a "laser" :)
100ft accuracy in the vertical plain
oh sorry, that would give a relative position
archivist: you mean my micro gps?
archivist: Actually, there would be ref point on each machine making ht eaccuracy nuts to butts
circle of error on gps is a egg shape
archivist: I just can't recall the name if it.
archivist: land surveyors use it which gives them accuracy in inches
anonimasu: that souns right. there's a land based thingy
still not good enough
lol, f yu say so
bah I hate this kybd
oh, dgps isnt it, there's another system they run in paralell
Yeah, Trimble has t
with a radio base station
With RFID chips being abundant, I'd suspect that they could be used for positioning in some aspect
JanVanGilsen: It uses the satellites AND a known land based tranmitter
[19:39:05] <Jymmm> http://en.wikipedia.org/wiki/Differential_GPS
I was suggesting that that was the name you where looking for ...
But there is another system that allows one to setup their own land based system for position accuracy. Say for a new constructon site, etc.
I just dont recall.
WAAS is what Trimble pushes - You set up a radio transmitter over a known point - then rove to 2 additional known points and viola - .5" accuracy
Topcon uses DGPS - use a cellphone to dial into the nearest transmitter for position correction in your area
vertical is still well off
WAAS needs 6+ satelaittes for accuray - DGPS need >14 for it to get decent accuracy
On WAAS - +/- 0.5"
the error is not the same h to v
Used to due surveys on mine sites all the time - it was spot on
if your known points for setting up the iste are good - your accuracy (assuming satelite availability) is +/- .1' on Z - even better on h
forgot it was in decimal feet
iste = site
still barn door for machining
I hope the EU makes their own system operable soon
like fire up the last 40 sattelites
For fine grading with a bulldozer - its high accuary )
err last 25..
GPS on grading equipment has eliminated a roughing step in heavy construction work - you can go right to finish grade - big cost and time saver
One could toss 3 transmitters on a machine (instead of using satellites). I figure if you can get .1" accuracy from something that's 20,000+ feet up, you can do far better when it's only 20 feet away
Some sites use a laser ceiling
accuracy is limited to the laser quality and setup
and distance to laser
mining for work - router hobby )
the laser ceiling only provides Z control though
That's why I thought of RFID chips to be used in some fashion... http://www.google.com/search?q=RFID+positioning&ie=utf-8&oe=utf-8&aq=t&rls=com.ubuntu:en-US:unofficial&client=firefox-a
they are cheap and abundant
does TOOL_CHANGE_POSITION use G53 or does it use the active offset?
acemi: I think G53, but it should be explained in the manual
G53 is nice
38C is nicer
we had 35C earlier this week
on wednesday to be precise
then 15C the next day
err .. what?
lol @ alex_joni
it's late over here :P
alex_joni: I know you recently got married and all, but did you totally forget what those are/were?
not _that_ recent ;)
That long, damn
Is anyone aware of a voice recorder that can still continue to record,even while a portion of what has been recorded already is played back?
it had a tape loop
I'm speaking of something that can be placed n your pocket
a picture http://birmingham.gumtree.com/birmingham/57/37942657.html
I guess the simplest solution would be to just carry two voice recorders instead.
Not ideal though
would be easy enough to do now with memory and A?D and counters to read from a different location
I've found most of the personal vice recorders pretty lacking in features.
Some timestamp, some don't
some save as seperate files, others as a continous file
The idea is that you could be recording 24hours a day, but have the ability to playback a portion for purposes of review as needed, but still not itterupt the recording process.
Jymmm: this looks nice: http://www.olympusamerica.com/cpg_section/product.asp?product=1369
good night all
jmkasunich_ is now known as jmkasunich
Jymmm: I has a cheaper Olympus purchased about 1 year ago. Can do 8 hours of continous recording.
when I stop and start a new recording - its a seperate file. Recording quality was good and the files were accessed by any music type player
for what it is worth.......
I'm having some trouble with generating a zero-crossing signal that corresponds to a 60Hz AC signal. When the voltage levels get close to 0V, the signal that I generate becomes unstable
btw, the AC signal ranges from +/-3.3V
I'm thinking of adding an external hysteresis circuit, but I need to know: Will adding this extra circuitry cause the comparator that I'm using to "suck" more power from the AC signal?
dan1mal is now known as Danimal
depends, technically yes, but if impedances are within reason, you wont notice
so another n00b question from me...so i got my spindle turning on and off, and now i want to control my vfd. Someone mentioned that i could use a optocoupler driven off my 5i20/7i42 to avoid having to get a DAC. Now, would i use a pwmgen to output a signal to the optocoupler? or would that just be a gpio?
pwmgen so you can vary the speed
ok thats what i thought, just wanted to be sure
pwmgen.N.value float in?
manual is kinda greek to someone with no background in this stuff