#robotics Logs

Dec 06 2013

00:00 MrCurious better call in repair
00:00 GargantuaSauce it never even gets stupid cold on the west coast
00:00 MrCurious its like 8C here now
00:01 MrCurious i mean 5C
00:01 Centauri heh, be glad you're not in Minneapolis
00:02 MrCurious i never really got the draw of minneapolis
00:03 Centauri Me neither, I was there for the summer, and escaped on halloween (thank gawd)
00:03 Centauri got out just before the temps *really* dropped
00:06 MrCurious rue_house: warm enough to survive?
00:06 rue_house yea
00:06 MrCurious aquire more catss
00:06 MrCurious they like to keep you warm
17:50 robotustra salut tout le monde
18:22 GuShH robotustra: tout le nerds
18:43 GargantuaSauce LES
18:43 GargantuaSauce god, get it right
19:44 robotustra :)
19:44 robotustra je suis pas francophon
19:44 robotustra je suis pas francophone
19:45 GargantuaSauce you had it right
19:46 robotustra ok
19:46 robotustra it's almost impossible to learn french
19:47 ace4016 lol
20:03 GuShh_ Tom_itx: how did those chinese bits go?
20:03 GuShh_ usable?
20:04 Tom_itx they are still on a slow boat from ....
20:04 GuShh_ hrm
20:04 GuShh_ I'm trying to figure out how to cut a slot in some aluminum tubing, I don't have a mill. I could maybe rig a vise for the lathe, but still unsure
20:04 Tom_itx i don't expect too much at less than a buck apiece
20:05 Tom_itx grind wheel
20:05 GuShh_ but it has to look neat
20:05 Tom_itx steady hand
20:05 GuShh_ otherwise I'd take the angle grinder for a ride
20:05 GuShh_ you know my hands are not that steady!
20:05 GuShh_ even though it nearly "self centers" (or rather follows the line)
20:09 GuShh_ Tom_itx: so far I broke a tiny endmill trying to mill the slot with the lathe, and I was going pretty fast but since it was a horizontal cut and at such small scale, without flood coolant it's not going to happen
20:09 GuShh_ fast as in the spindle, not the feed.
20:09 GuShh_ the endmill wasn't clearing the chips
20:10 GuShh_ might need less flutes
20:10 GuShh_ dang it where are my hole saws... I need to finish a small wood project
20:11 GargantuaSauce you would
20:11 GargantuaSauce hahahahar
20:11 GuShh_ o.O
20:11 GuShh_ I really really need a CNC mill
20:11 GuShh_ or router just to start with.
20:13 GuShh_ making some curtain brackets in olive wood
20:13 GuShh_ would be nice to have the sides engraved
20:14 Shh_ can't carve wood at
20:15 GuShh_ just mortises and tenons...
20:16 GuShh_ which is a basic skill I guess, not an artsy type here...
20:20 robotustra I had such idea https://lh5.googleusercontent.com/-2ONMJgKFTW8/UjP1tR3BgzI/AAAAAAAACII/PLJ9kD8WpOU/w426-h286/pop+up+garage.jpg
20:20 GargantuaSauce great way to destroy your garden hose
20:21 robotustra https://lh5.googleusercontent.com/-IRxKKxA3veI/UjF2uM27OII/AAAAAAAACA0/Jj1kVc3fbq4/w426-h441/1002617_436114373165899_409399833.jpg
20:24 robotustra https://lh6.googleusercontent.com/-HFIQUfpZ1XM/Ugu9WAcXRLI/AAAAAAAABZo/MO4g3bWY3B0/w426-h507/1001729_415332291909709_1.jpg
20:25 GuShh_ robotustra: too expensive
20:25 GuShh_ oh I like the last one
20:26 robotustra https://lh5.googleusercontent.com/-E-bCgZOy4kI/UfXuIlDKFGI/AAAAAAAABAU/fENcuCDHR-A/w426-h656/757.jpg
20:30 robotustra https://lh5.googleusercontent.com/-BnanloX7yNQ/UcQEQGs32vI/AAAAAAAAACk/6nsepwnEZJY/w426-h308/255519_270979819679356_1.jpg
20:52 MrCurious its time to cross the wires, and spin the tires!
20:54 GargantuaSauce how's the mill coming
20:54 MrCurious on hold waiting for the replacecment supported rails
20:54 GargantuaSauce ah yeah
20:54 MrCurious as teh slop was not acceptable
20:55 Tom_itx shoulda got rails
20:55 Tom_itx are you gettin new rods premounted?
20:55 MrCurious should have... but i have now, so corrected
20:55 MrCurious i think the 20mm unsupported ones would be good for a delta bot
20:55 MrCurious so not a full write off
20:59 Tom_itx i'm becoming more convinced delta are a waste of time
20:59 MrCurious http://www.3dprintedsculpture.com/2013/08/rostock-delta-robot-mechanics.html
20:59 MrCurious why is that?
21:00 Tom_itx i think you need real precise parts with no slop
21:00 MrCurious probably
21:00 Tom_itx and at the hobby level that's hard to get
21:00 MrCurious like the kind you can make with a cnc?
21:00 Tom_itx a _good_ cnc
21:00 MrCurious and like one would find with 20mm linear rods and bearing blocks
21:01 MrCurious well, that eliminates me :)
21:01 Tom_itx would be an awful lot of work to find out
21:02 MrCurious thats a thought, should other lucrative activities ever bid for my attention
21:03 MrCurious of cource i do have 1/3 of an eventor bot done
21:03 MrCurious so i have a fall back plan
21:03 MrCurious i think that is the alure of them...
21:04 MrCurious that they arent yet super perfected and simplified and factored down to minimal components
21:04 MrCurious i mean if thats what we were after, we would just buy legos or something
21:05 MrCurious calcium is a metal right?
21:06 GargantuaSauce everything that's not on the upper right chunk of the periodic table is
21:06 Jak_o_Shadows Most things are metal.
21:06 Tom_itx even the plate in your head
21:06 MrCurious so life has metal alloy bones fabricated utilizing nano particle construction
21:07 MrCurious we are terminators...
21:07 GargantuaSauce http://en.wikipedia.org/wiki/Hydroxyapatite
21:07 GargantuaSauce not an alloy
21:08 MrCurious seems an alloy
21:08 GargantuaSauce alloys are not compounds with nonmetals
21:09 MrCurious so the carbon in carbon steel?
21:09 MrCurious still makes me think of 4 schwartezeneger terminators in a room trying to make a mouse...
21:10 Jak_o_Shadows there are a lot of types of steel
21:11 MrCurious just figured that bones were in essence a designer material, fabricated on a near atomic level
21:18 Tom_itx meh, just leftover parts tossed together with a bit of glue
21:18 MrCurious hot glue!
21:22 Tom_itx i should be playing with these new cards i got
21:22 Tom_itx being kinda lazy
21:22 MrCurious what cards?
21:23 Tom_itx more io for the mill
21:23 Tom_itx and to play
21:23 MrCurious adding some extra axis's
21:23 Tom_itx one is a 48ouput card for relays etc
21:24 Tom_itx the other is a 32 input 16 output
21:24 Tom_itx with analog and encoder for a hand wheel
21:24 Tom_itx that should be plenty of io for a bit
21:24 MrCurious your getting closer to the base metal of the electronics than i wanted to...
21:25 Tom_itx huh?
21:25 MrCurious do you have a dedicated uC for g-code to signals
21:25 Tom_itx dedicated pc
21:25 Tom_itx running linuxcnc
21:25 MrCurious ahhh
21:25 Tom_itx with mesa cards for better step speed etc
21:25 MrCurious have seen some people using avr to convert g-code to motor control
21:25 Tom_itx 40000 steps per inch
21:25 Tom_itx that's for toys
21:26 Tom_itx http://store.mesanet.com/index.php?route=product/product&path=69_70&product_id=114
21:26 Tom_itx http://store.mesanet.com/index.php?route=product/product&path=69_70&product_id=123
21:26 Jak_o_Shadows I don't understand the reprap people's dislike for having a PC for their machine.
21:27 Tom_itx i got a D525 atom pc for it
21:27 Tom_itx fanless
21:27 Tom_itx i really like it
21:27 Jak_o_Shadows Yeah. I'd start with an old P4 I have, but it gives you the option of upgrading
21:28 MrCurious i have a 3ghz 1 core p4 for my cnc control
21:28 MrCurious debating a dual core celeron for it instead though to save space and power
21:28 Tom_itx speed isn't the issue, rather latency
21:28 Tom_itx some good mb's fail latency
21:29 GargantuaSauce personally i'd say the best tool for the job would be a microcontroller, but one that wasn't designed 20 years ago
21:29 Tom_itx i use the parport and offload the work to the mesa cards running at 50Mhz
21:29 Jak_o_Shadows I even have a parallel port on that computer. AAAANd a serial port.
21:29 Tom_itx GargantuaSauce, fpga
21:30 Tom_itx these cards are serial
21:30 Tom_itx rs422
21:30 Tom_itx 2.5mhz
21:30 GargantuaSauce yeah limiting the update speed to 10khz
21:30 Tom_itx they could go faster but no need
21:31 Tom_itx just using them for limit switches pendants and slow stuff like that
21:31 Tom_itx saving the main card to do the dirty work
21:31 Tom_itx plenty fast for that
21:32 Tom_itx i just need to sit down and do some rewiring now
21:40 MrCurious GargantuaSauce: so an arm?
21:41 GargantuaSauce yeah any cortex-m4f with plenty of io
21:41 MrCurious i was thinking that the a20's are cheap as hell now
21:41 MrCurious enough speed to embed some intellegence close to the io
21:42 Tom_itx some were working on the bbb for linuxcnc
21:44 MrCurious surprised bobody has abstracted the layers to easily facilitate swaping low level cpu's next to the control level
21:45 MrCurious like an i2c io expander or spi io expander
21:49 Jak_o_Shadows AMD has some nice low end cpus, that beat the hell out of intel
21:49 GargantuaSauce i think it makes more sense to use a microcontroller at the bottom. and then something more fancy on top to implement a user interface or whatever
21:50 GargantuaSauce i am pretty sure even an rtos has timing limitations on more complex architectures with MMUs and the like
21:51 GargantuaSauce (not that many of those microcontrollers aren't powerful enough to do the whole stack including graphics)
21:57 MrCurious but an arm would be like BBB
21:57 MrCurious be nice to see it hang off ethernet
21:57 MrCurious with a front end on a pc
21:57 Tom_itx i forget how they connected it with linuxcnc
21:58 GargantuaSauce many of these mcus have ethernet peripherals
21:58 Tom_itx maybe a terminal
21:58 GargantuaSauce (and i agree that that would be a near-ideal interface)
22:01 GargantuaSauce something like the lpc4357 would be just super
22:02 GargantuaSauce that on a board with some io buffers, a little touchscreen, and an ethernet phy would do the job quite nicely and cheaply i think
22:03 GargantuaSauce oh and some extra flash i guess
22:07 GargantuaSauce i bet the bom could be <$30 in small quantities
22:07 GargantuaSauce kickstart now, implement later
22:18 Shh_ kickstarts GargantuaSauce's
22:18 GargantuaSauce thank me when you're rich
22:19 GuShh_ I wouldn't have time to, I'd be too busy snorting pixie dust
22:42 MrCurious it does seem a good kickstarter idea
22:45 MrCurious so it would basically be a low level layer for driving signal, reading switches...
22:45 MrCurious mid layer for execuing g commands
22:46 MrCurious and a top layer for network transport of g-commands
22:46 MrCurious then a pc program to get g-codes and send them
22:47 MrCurious maybe some visualization
22:47 GargantuaSauce wouldn't even have to be a pc program
22:47 GargantuaSauce a web interface served by the device
22:47 MrCurious i am thinking how to interface it to existing infrastructure
22:47 MrCurious optimize later to work with the new native interface
22:48 GargantuaSauce anyway it's not really commercially feasible i don't think, not without closed saucing it
22:48 GargantuaSauce because as soon as you release the hardware and it proves remotely possible, clones will appear for half the price
22:48 MrCurious well, beauty of kick starter is, you release the ip
22:48 MrCurious andthe funders pay more knowing that will happen
22:49 GargantuaSauce maybe
22:49 MrCurious front load the profit
22:50 MrCurious things like this idea really need to be unfettered and free to fuel the community, and see what comes next...
22:51 MrCurious i like the idea of a ethernet connected cnc machine
22:51 MrCurious that works like an appliance