#robotics Logs
Nov 19 2013
#robotics Calendar
00:11 wildmage rue_house, it's very much turning into a an engineering discipline though
00:11 wildmage rue_house, the guys who are doing the DARPA grand challenges are learning all the right skills
00:11 wildmage rue_house, it requires a lot of extensive testing to make the algorithms work well
00:11 wildmage of course, I'm doing the Dark Mapper, which is a little different from what other people are doing
00:13 wildmage now I have to lay the groundwork for my asteroid mining venture.... although this could take 20 years
00:13 rue_house its funny
00:14 rue_house sounds like programming my mowerbox
00:14 rue_house heh
00:14 rue_house mowerbot
00:14 rue_house the slightest difference in one timer will make it go from finding cliff edges to jump off vs humping shrubs
00:15 rue_house if you get the values just right, it goes after extension cords and garden hoses
00:15 wildmage yeah, that's the brittleness of decision logic on raw sensor data
00:15 rue_house but I'v learned a lot
00:15 wildmage I've had to use probabilistic approaches as a last resort
00:16 rue_house you dont program what it does, you program what its not to do
00:16 wildmage yeah, just getting a robot to survive is challenge enough... getting it to do something useful is a bonus
00:16 rue_house mine does something useless the longer its out
00:16 rue_house er, usefull
00:16 rue_house as everywhere it goes the lawn is mown
00:17 rue_house and the odds are, the longer its out there, the less unmowen lawn there will be
00:18 rue_house I want to make one to rescue dandilion flowers
00:18 rue_house a 'bring them back to base' thing
00:18 rue_house verry easily identified
00:19 rue_house it is round?, is it yellow? BRING IT BACK!
00:29 GuShH rue_house: lol
00:29 GuShH you are insane, but in a good way.
00:30 MrCurious is he crying for pe-cycles?
08:59 GuShH http://www.wired.com/images_blogs/wiredscience/2009/09/kegerator_arkeg1.jpg
09:06 Tom_itx it's missing the helmet and connecting tube
09:07 GuShH lol
09:32 GuShH Tom_itx: still looking at the guy's site... http://gnipsel.com/shop/hardinge/hardinge-13.xhtml I find it amusing he's got all these machines and he can't build a friggin straight little table out of scrap
09:34 adam789654123 sawhorse table
09:34 GuShH neh
09:35 GuShH one leg is fairly crooked compared to the rest
09:35 GuShH it's an asshole's table.
09:35 adam789654123 haha
09:35 adam789654123 it does look funny
09:35 adam789654123 i guess he was buisy building something else when he built that
09:35 GuShH let's buy CNC machines, build a shop... but we can't afford a chair or a table now, let's eat dust for the rest of the year! yey!
09:35 ShH g
09:36 adam789654123 hahahaha
09:36 Tom_itx that may have been in his old shop
09:36 adam789654123 he has the same chair i am using
09:36 GuShH adam789654123: sometimes you don't really care, specially if you haven't got any OCD tendencies... so I've built a few things fairly crooked for a one-off purpose
09:36 GuShH adam789654123: lol
09:36 chris_99 make a chair with your CNC machine GuShH
09:36 GuShH I see those chairs on the street all the time with a missing leg, I think people love to kick them off and watch others fall flat on their ass.
09:36 adam789654123 but my other equipment is shit, so..... it kind of works
09:36 GuShH chris_99: no sir I don't own one sir.
09:36 chris_99 ah heh
09:37 GuShH I'm just pointing out something I thought was funny (the table, having all those tools!) that's all
09:37 adam789654123 i havent stoped lauphing since i saw the picture
09:37 GuShH adam789654123: bah, what equipment?
09:38 GuShH I'm not going to talk about his keyboard, I have one just like that on my 286, which still runs... I fire it up on ocassion.
09:38 GuShH nostalgia and all.
09:38 adam789654123 who me? 13 year old computer
09:38 GuShH that's a bad luck number!
09:38 adam789654123 has windown 98 sticker
09:38 adam789654123 woops xp
09:39 GuShH Tom_itx: is that the DOS CNC machine or is it another one?
09:39 Tom_itx linux
09:39 GuShH I find the site hard to browse, but I love the content
09:39 adam789654123 might be a temp setup
09:39 adam789654123 yea linux
09:39 adam789654123 oh
09:39 adam789654123 sorry
09:39 GuShH I did read he had trouble installing linux until a cnc distro was made
09:39 Tom_itx he's got 2 or 3
09:40 GuShH neat
09:40 Tom_itx gtg
09:40 GuShH what does he produce with them?
09:40 GuShH oh noes!
09:40 ShH gives Tom_itx a manly
09:40 Tom_itx he mfgs tooling for companies
09:40 Tom_itx fixtures etc
09:40 GuShH I'd like to be his midget one day!
09:41 adam789654123 real time linux was an issue at one time, so
09:42 adam789654123 something to do with the kernel i think
09:42 GuShH yeah but now we've got enough opensource slaves to code linux in real time for us! they couldn't keep up previously!
09:42 ShH h
09:42 adam789654123 hahaha
10:00 GuShH adam789654123: notice the feet http://gnipsel.com/shop/machines/machines-01.xhtml
10:18 adam789654123 GuShH: now that's custom!
10:21 GuShH so it seems
10:22 adam789654123 even if he didn't make the feet, he still had to attach them
10:22 GuShH he probably plasma cut them on his cnc
10:22 ShH can weld just as fine, thank yo
10:23 adam789654123 :)
10:23 adam789654123 i can sure appreciate it
10:24 adam789654123 metalworking is usefull
10:24 adam789654123 i often would love to build things with metal
10:25 GuShH it's not as fun as it looks
10:25 adam789654123 right
10:25 adam789654123 well
10:26 adam789654123 useful at least
10:26 GuShH you often end up covered in black sooth and a broken back.
10:26 adam789654123 right
10:26 adam789654123 that is actually my main concern
10:26 adam789654123 that keeps me from it
10:26 GuShH it is?
10:26 adam789654123 breathing that crap in
10:26 GuShH do it outside
10:26 adam789654123 yea
10:26 adam789654123 lungs
10:26 adam789654123 right
10:26 GuShH I don't weld that often to worry about it
10:27 adam789654123 right
10:27 adam789654123 but something to think about anyway
10:27 GuShH I've had to weld zinc plated steel and that was nasty
10:27 adam789654123 for professional welders
10:27 GuShH you feel it in your mouth instantly
10:27 GuShH gets nasty quite fast.
10:27 adam789654123 right
10:27 GuShH the hell with them, they most likely already have a union
10:27 adam789654123 i was thinking about learning it, and checked out occupational hazards
10:28 GuShH hobby welder != professional welder
10:28 adam789654123 something NOT to do regularly
10:28 adam789654123 right
10:28 adam789654123 so maybe i will pick it up
10:28 GuShH plus in commercial applications you'd have to use a fume extractor indoors
10:28 GuShH by law in the US I believe
10:28 adam789654123 but it has to be a hobby
10:29 adam789654123 for me to do it
10:29 adam789654123 you could build some awsome stuff though
10:29 adam789654123 but you also need to have decent equipment
10:29 GuShH such as?
10:29 adam789654123 well
12:28 ShH kicks KongfuPanda's c
12:47 ngfuPanda (ノಠ益ಠ)ノ彡┻â”
15:44 GuShH KongfuPanda: fluid in reprapism?
15:44 KongfuPanda GuShH, woot?
15:45 GuShH reprap
15:46 KongfuPanda no idea
15:47 KongfuPanda I'm trying to setup coin mining
15:47 KongfuPanda and become rich
15:47 GargantuaSauce bit late
15:47 KongfuPanda yeah :(
15:47 GargantuaSauce waste of electricity at this point
15:48 KongfuPanda I'm mining this "litecoin" thing, because I thing bitcoin is useless anymore
15:50 GuShH you are spending more on electricity and internet access than you are getting back
15:52 KongfuPanda I don't pay for electricity per se
15:52 GuShH one way or another you are
15:52 KongfuPanda we just pay rent and bills are included
15:52 GuShH you _are_ páying for it, rent will go up
15:52 KongfuPanda naa
15:52 GuShH yaa
15:54 KongfuPanda I'll try to setup a mining tool on my computer in the lab
16:03 GuShH KongfuPanda: what makes you think it's worth it? :/
16:03 GuShH Just curious
16:04 KongfuPanda maybe I can mine a few coins and then they increase in value hundreds of times
16:04 GuShH wishful thinking :p
16:05 KongfuPanda there is a story about a guy who bought $27 boitcoins and now they are worth 810 000
16:10 KongfuPanda I want to be rich :(
16:10 GuShH It's over though
16:10 GuShH KongfuPanda: if you want to be rich... get rid of your morals first
16:10 GuShH become a real dipshit
16:11 KongfuPanda a guy yesterday was saying to me that he made 100k last month on bitcoin sales
16:11 GuShH step over anyone who gets in your way
16:11 GuShH put your family aside, let a wild animal fuck 'em for all you care
16:11 GuShH give aids to everyone who gives you a bad look
16:11 KongfuPanda GuShH, moo moo moo
16:11 GuShH and then you might start to become rich and live forever
16:11 GuShH :p
16:11 GuShH KongfuPanda: either that or become reborn instantly rich
16:11 GuShH find a way for donald trump to adopt you?
16:12 GuShH KongfuPanda: they're selling air
16:12 GuShH thus, no morals
16:12 KongfuPanda oh come up with an idea
16:12 GuShH they're dipshits, and that's how you actually make money either border line legally or illegally
16:12 KongfuPanda I need an idea like facebook
16:12 GuShH haha
16:12 GuShH fartbook
16:12 GuShH there ya go.
16:12 KongfuPanda great idea !
16:12 GuShH so when someone enters, the book opens and lets a fart rip out
16:12 GuShH find a way to make canned farts first.
16:13 GuShH mexico could be your primary producer.
16:13 GuShH KongfuPanda: we all need money
16:13 GuShH it's a fact..
16:13 ngfuPanda Lindsay, - yes sir ? - I have a fart scheduled for 2 o'clock, can you push it up to now please? - very good, sir - ppprrrrrrrrrrr
16:14 KongfuPanda yeah, I get it
16:14 GuShH lol
16:15 GuShH you must really have your SHIT TOGETHER if you've got your farts all scheduled up.
16:15 ShH hifives KongfuP
16:15 GuShH let's do some standup comedy for beer money!
16:15 KongfuPanda http://www.youtube.com/watch?v=7YEFcOz0loA
16:16 KongfuPanda GuShH, I think I'm an inventor. I constantly have many ideas
16:16 GuShH my favorite clip is the bird shif one
16:16 GuShH KongfuPanda: a failed one
16:16 GuShH because you never manage to materialize them?
16:16 KongfuPanda of course I do
16:16 KongfuPanda in the lab
16:16 GuShH I have plenty ideas, just nobody I trust to work with.
16:17 KongfuPanda but I never have time to do all of them, some of them are very good in principle. I convinced my supervisor to allocate students to me for supervision, so that they do what I think may be interesting. This year I got one, next year maybe two
16:18 GuShH http://www.youtube.com/watch?v=xeCp2DsE7kI
16:18 KongfuPanda but these are just research ideas
16:18 GuShH let's sell cans of air
16:18 KongfuPanda I need to go into industrial environment and innovate products
16:18 GuShH air from paris, china...
16:18 GuShH mexico (just a fart)
16:18 GuShH so on.
16:19 GuShH you could travel your world with an air compressor!
16:19 GuShH your/the
16:19 GuShH oh snap, now you know I'm not from here
16:20 KongfuPanda GuShH, http://www.youtube.com/watch?v=uFgyg7ezM6k
16:22 GuShH glue an arduino to one of those and you've got a product
16:27 ngfuPanda pats GuShH with a used buttscrat
16:28 GuShH eew
16:52 GuShH Tom_itx: any better fluids than motor oil for turning aluminum?, not tapping just general lubrication
17:31 Tom_itx water based cutting fluid
17:32 Tom_itx motor oil is for keeping motors running in tip top shape not abusing your tool on aluminum
18:03 GuShH Tom_itx: motoroil is cheap and that's what I have handy though
18:04 GuShH I don't want to use water based fluids
18:04 GuShH unless they're stabilized in some way to avoid rust
18:06 GuShH surely it's better than nothing though, the machine oil or motor oil
18:06 GuShH ran out of the former
18:06 GuShH this ebay guy is driving me nuts, calling all day... we had a 10 minute chat and then his phone died, couldn't call back and he's not answering any messages... bleh
18:07 Tom_itx you selling or buying?
18:07 GuShH buying, but he bought one of my items, it's complicated.
18:07 Tom_itx must be. i wouldn't call anybody off ebay
18:08 GuShH I never hit any "buy now" buttons he just assumed I wanted it and he bought one of my items
18:08 Tom_itx so he expected you to buy one of his?
18:08 GuShH he claims he's sick of answering the messages all the idiots leave and he would rather put it on hold if I'm interested in buying it within a week or two
18:08 Tom_itx what is it?
18:09 GuShH yeah because I left him a few questions before and he thought I really wanted it
18:09 GuShH Tom_itx: it could be anything!
18:09 ShH chuc
18:09 GuShH it's a toy.
18:09 Triffid_Hunter if he's being hit with a barrage of questions, his description must suck
18:10 GuShH it's one of those items that requires specific questions
18:10 flatr0ze Hello.
18:10 flatr0ze Does anyone know what would be the strongest/fastest linear actuator out there? I need about 9" and hopefully stepper (for use in CNC).
18:11 GuShH Tom_itx: I like to practice target shooting, problem is you can't legally shoot actual firearms where I'm at, that is.. a residential zone. So I'm looking into PCP rifles, this guy is selling one and I was interested to know about a few of it's specs (they're all modified somehow) ... he assumed I had the cash in hand, I don't.
18:11 GuShH I already have one, this is better. I would sell the other one anyway.
18:11 GuShH All quite irrelevant though, I feel ebay-raped.
18:12 GuShH Such a persistent seller... makes me wonder if he would even send the item at all. Given the price I would not pay upfront and expect him to send it later on.
18:12 Tom_itx flatr0ze the biggest and best will only last for a day
18:13 Tom_itx there will be something to replace it by then
18:13 Tom_itx but if you're serious, look on PBC linear
18:14 flatr0ze I am serious. Thanks, looking it up now...
18:15 flatr0ze I'm looking for something like a low-resolution screw. I have to drive it 9" in 1.5 seconds.
18:15 Tom_itx then you don't want the strongest/fastest
18:15 Tom_itx linear slides are it
18:16 Tom_itx will go 9" before you can blink
18:16 Tom_itx not practical for a ballscrew
18:24 Tom_itx flatr0ze are you making a reprap?
18:27 Tom_itx http://www.youtube.com/watch?v=-dMKXUPLMW0
18:30 Tom_itx http://www.youtube.com/watch?v=BhcZBr38Kmc
18:31 Tom_itx servo version
18:35 Tom_itx http://www.youtube.com/watch?v=jleS4nog5UQ
18:35 Tom_itx you get the idea
18:42 GargantuaSauce i'd let jenny mount my linear axis
18:42 GargantuaSauce ifyaknowwhatimean
18:42 Tom_itx jenny's a slut
18:43 GuShH who?
18:43 Tom_itx but the video was a good demo of how they work
18:44 GuShH That girl is called Tamara though
18:44 Tom_itx uh huh
18:44 Tom_itx that's her working name
18:44 GuShH lawl
18:45 GuShH I have a theory with regard to mouth size vs cooch size. Shit did I just write this "out loud"
18:45 GuShH Tom_itx: I think I'm getting better at manual feeding, of course I was cutting too slow http://gushh.net/tmp/dscn4536f.jpg
18:45 GuShH I can't quite do the hand-over-hand technique with my bear hands
18:46 Tom_itx that's what the feed is for
18:46 ShH really wants to put a 3 phase and a vfd on this t
18:46 GuShH yes power feed is ok, but I need the skill.
18:46 Tom_itx hell you don't even have any dings in that thing yet
18:46 GuShH yes just the one
18:47 GuShH on the side of the bed
18:47 GuShH thanks to a moment of stupidity.
18:47 GuShH (jaw dropped)
18:47 GuShH oh but not on the jaws, I haven't touched them yet with the tool.
18:47 GuShH I can see potential damage.
18:48 Tom_itx btw GuShH, that bar is undersize
18:48 GuShH so the "marring" is attributed to the tool smearing the metal instead of cutting it?
18:49 GuShH Tom_itx: what?, there are no dimensions just a test cut, and it's a tube actually
18:49 GuShH I'm still adjusting this lathe!
18:50 Tom_itx well, it's still undersize
18:51 GuShH o.o
18:51 GuShH if there are no blueprints, how can it be?
18:51 Tom_itx i can see it from here
18:51 Tom_itx i swear it is....
18:51 GuShH NO
18:51 ShH fr
18:52 Tom_itx i wish i had that lathe
18:52 GuShH I'm too lazy to change the belt for different speeds, it's a fact.
18:52 GuShH that's why I'm always cutting too slow.
18:52 Tom_itx my feed is set up for a decent cut but i don't use it that often
18:52 Tom_itx i'm just that good... :D
18:53 Tom_itx not.
18:53 GuShH well that's another thing, the lowest feed speed right now due to the gears I'm using would be worse than what I did by hand
18:53 ablegreen what are the pros and cons of using a quadrature encoder over a reed switch for finding the velocity of a wheel?
18:53 GuShH I'm not sure I care that much about tooling marks anymore
18:54 GuShH here's the marring with different light http://gushh.net/tmp/dscn4534f.jpg
18:54 Tom_itx ablegreen quite a bit
18:54 GuShH it's caused by the tool pushing the metal back in and smearing it?
18:54 ablegreen tom_itx: can you explain?
18:54 Tom_itx you gonna spin the reed switch?
18:55 GuShH and is that due to chatter? in this case it's quite a flexible piece
18:55 Tom_itx quad encoders give you alot more resolution
18:55 GuShH I don't know why you'd want to have a chinese lathe like this one at all
18:55 ablegreen tom_itx: I see
18:56 Tom_itx a reed switch would read one tick per rev depending on how you set it up
18:56 Tom_itx an encoder could get you tens of thousands of ticks per rev
18:56 ablegreen tom_itx: can you recommend a 1/4 inch shaft encoder?
18:57 Tom_itx HEDS encoders are good
18:57 ablegreen okay, i will look that up
18:58 Tom_itx http://tom-itx.dyndns.org:81/~webpage/maxbot/image006.jpg
18:58 Tom_itx there's the wheel from one of mine
18:59 Tom_itx http://tom-itx.dyndns.org:81/~webpage/maxbot/maxbot_index.php
18:59 ablegreen tom_itx, nice, that's a lot of resolution
18:59 GuShH those linear stages are neat.. how much for a pair of big ones?
18:59 Tom_itx alot
18:59 GuShH :<
19:00 GuShH IT BETTER COME WITH THE BIRD
19:00 ablegreen tom_itx: can you recommend a place to get heds encoders?
19:01 Tom_itx http://www.automationdirect.com/adc/Overview/Catalog/Sensors_-z-_Encoders/Optical_Rotary_Encoders?gclid=CITHzr6R8roCFRES7AodqkIAIQ&s_kwcid=AL!3683!3!20300044343!e!!g!!encoders&ef_id=ULDp6QAAGr5fszWw:20131120004509:s
19:01 Tom_itx they've got encoders
19:01 Tom_itx more industrial grade
19:02 ablegreen 89 bucks isn't bad
19:03 Tom_itx i can't think of the other place
19:03 ablegreen tom_itx: do you happen to know if they work well with arduinos?
19:03 Tom_itx us digital maybe
19:03 Tom_itx i doubt they're gonna keep up with the counts and be able to do much else
19:04 Tom_itx you can get coarser ones
19:04 Tom_itx i've got a few 500 count ones
19:05 Tom_itx http://tom-itx.dyndns.org:81/~webpage/motors/focusring12.jpg
19:05 ablegreen clock rate of arduinos are too slow or something?
19:05 Tom_itx there's a pair of em on that assembly
19:05 ablegreen i see
19:05 Tom_itx they might keep up, you'd have to do the math
19:06 Tom_itx http://www.usdigital.com/
19:06 Tom_itx those might suit you better
19:07 ablegreen okay, i will look at those
19:07 ablegreen this is for a bike wheel btw
19:07 ablegreen not actually on a bike frame
19:07 Tom_itx for mileage?
19:07 Tom_itx it just depends what you're doing with em
19:08 Tom_itx and how accurate a count you need
19:08 Tom_itx you're not gonna ride it backwards so you may not need quadrature
19:08 ablegreen it doesn't have to be that accurate
19:08 ablegreen it's hard to explain but basically my group is building a push pull version of a wheelchair
19:09 ablegreen we need the wheel velocity to determine how far to extend a linear actuator
19:09 ablegreen this is more of a proof of concept project, so it's just one wheel on a piece of plywood so not much force
19:11 Tom_itx http://www.mouser.com/ProductDetail/ALPS/EC11E15244B2/?qs=%2fha2pyFadugMG2RDp45gzKy3E%252bJw2bg9wyx%252blVW1GEpKn%2fqxa66ihw%3d%3d
19:11 Tom_itx more of a hand wheel encoder but that might work
19:11 Tom_itx 30 count
19:12 Tom_itx like you'd find on a digital volume control etc
19:13 Tom_itx has detents though, you may not want that
19:13 ablegreen i think that might be too light
19:13 Tom_itx probably
19:14 Tom_itx but you don't need those industrial ones either
19:14 ablegreen true
19:14 ablegreen anything in the middle? haha
19:15 Tom_itx the usdigital site
19:15 ablegreen yeah they look good
19:15 ablegreen incremental or absolute?
19:16 Tom_itx the ones i have are the heds 9000 series
19:16 Tom_itx http://usdigital.com/products/encoders/incremental/rotary/kit/E5
19:17 Tom_itx or such
19:18 Tom_itx http://usdigital.com/products/encoders/incremental/modules/EM1
19:19 ablegreen the "shaft" encoders are basically the same as the one you just posted but with a shaft right?
19:19 Tom_itx pretty much
19:19 Tom_itx you would mount these to a shaft
19:19 Tom_itx like the back of a motor
19:19 ablegreen ah
19:20 ablegreen my groupmate just said to get one with a shaft
19:20 ablegreen there are so many versions of them on that site
19:20 Tom_itx http://usdigital.com/products/encoders/incremental/rotary/shaft/S5
19:21 Tom_itx http://usdigital.com/search?searchQuery=shaft+encoders
19:21 Tom_itx take your pick
19:22 Tom_itx i'd find one on ebay
19:22 ablegreen why do some shaft encoders provide torque? what is the purpose?
19:23 Tom_itx some applications may require knowing that
19:29 ablegreen tom_itx: thanks so much!
19:30 Tom_itx http://www.ebay.com/itm/3pc-500-line-rev-IP54-6krpm-quadrature-optical-encoder-/400314484489?pt=LH_DefaultDomain_0&hash=item5d349a4709
19:30 Tom_itx http://www.ebay.com/itm/3pc-1000-line-rev-IP54-6krpm-quadrature-optical-encoder-/280647960133?pt=LH_DefaultDomain_0&hash=item4157ec0645
19:31 Tom_itx 1" body
19:37 ablegreen tom_itx: are those sold only in bulk?
19:37 Tom_itx i dunno, i just clicked
19:43 Tom_itx http://www.ebay.com/itm/Encoder-600P-R-Incremental-Rotary-Encoder-AB-phase-encoder-6mm-Shaft-W-coupling/281206555918?rt=nc&_trksid=p2047675.m1851&_trkparms=aid%3D222002%26algo%3DSIC.FIT%26ao%3D1%26asc%3D163%26meid%3D2824268503151190260%26pid%3D100005%26prg%3D1088%26rk%3D3%26rkt%3D4%26sd%3D151024667992%26
19:43 Tom_itx http://www.ebay.com/itm/Scancon-Rotary-Encoder-500-PPR-New-Sealed-Boxes/300931851418?rt=nc&_trksid=p2047675.m1851&_trkparms=aid%3D222002%26algo%3DSIC.FIT%26ao%3D1%26asc%3D163%26meid%3D2824268503151190260%26pid%3D100005%26prg%3D1088%26rk%3D2%26rkt%3D4%26sd%3D151024667992%26
19:45 GuShH spam spam spam
19:46 Tom_itx
19:46 Tom_itx
19:46 Tom_itx
19:47 Tom_itx GuShH send me a set of linear slides
19:52 ablegreen tom_itx: thanks, I think we're going to go with a us digital one. where can we buy a connector? can't seem to find one on the us digital site
19:53 Tom_itx call em
19:53 Tom_itx or get one with wires out the back
19:55 Tom_itx http://tom-itx.dyndns.org:81/~webpage/avr/atmega328/PCINT0/quadrature/
19:55 Tom_itx quadrature code i tested a few with
19:59 ablegreen tom_itx: thanks! we're going to use an arduino though
19:59 ablegreen tom_itx: i found this article...maybe it's a solution? http://www.hessmer.org/blog/2011/01/30/quadrature-encoder-too-fast-for-arduino/
20:00 Tom_itx just get one with less resolution
20:00 Tom_itx doesn't sound like you need it
20:01 Tom_itx i don't care for using someone else's libs
20:01 Tom_itx i'd rather know how the code is written
20:01 Tom_itx than rely on a lib and have problems down the road with it
20:01 ablegreen tom_itx: we don't have time to understand how it's written :P
20:03 ablegreen tom_itx: so if an encoder has a CPR of 64 does that mean it can give an arduino 64 readings per revolution?
20:03 Tom_itx i got one off an old printer i'm using on my cnc spindle
20:03 Tom_itx it's only 28 count iirc
20:03 Tom_itx works fine
20:03 Tom_itx yep
20:03 ablegreen nice
20:04 Tom_itx for your application you don't need a bazillion counts
20:06 ablegreen i don't think we do yeah
20:06 Tom_itx http://tom-itx.dyndns.org:81/~webpage/cnc/psu/encoder_disk1.jpg
20:07 robotustra evening
20:07 robotustra to control the speed?
20:08 robotustra how are you going to control it?
20:12 ablegreen reading the speed
20:12 ablegreen not controlling it
20:16 Tom_itx 64 per channel
20:16 Tom_itx 90 deg out of phase
20:16 Tom_itx so you can detect direction as well
20:23 ablegreen tom_itx: I see, thanks
20:24 Tom_itx so once again for your application you may not need quadrature
20:25 Tom_itx you could use one channel of it
20:25 Tom_itx and just read the count
20:25 Tom_itx use the int0 interrupt for it
20:29 ablegreen tom_itx: so quadrature just allows you to detect direction?
20:29 Tom_itx yep
20:30 Tom_itx for the most part
20:30 Tom_itx you _could_ just read the rising edge of both channels and get 2x
20:30 Tom_itx quad reads rising and falling edges
20:31 ablegreen tom_itx: i see, thanks.
20:32 Tom_itx http://en.wikipedia.org/wiki/Quadrature_encoder#Single-track_Gray_encoding
21:40 flatr0ze Tom_itx: sorry, I had to go somewhere... It's a robotic dishwasher
21:40 flatr0ze a dish goes in, then the robotic mechanism scans it
21:40 flatr0ze *cleans it
21:41 flatr0ze on the way in, there's a sensor array to determine the position of the dish and size + depth
21:41 flatr0ze I'm using an array of 20 ultrasound scanners
21:41 flatr0ze it's like a toaster
21:42 flatr0ze so I'm trying to make the cleaning/drying nozzle rotate fast enough
21:42 Tom_itx that's a bit overkill for a dishwasher.. you think?
21:42 flatr0ze and it needs strength
21:42 flatr0ze it's a one-dish-at-a-time dishwasher
21:42 flatr0ze and it's just a prototype
21:42 flatr0ze we got patents
21:42 Tom_itx not very efficient either :)
21:42 flatr0ze well...
21:42 flatr0ze think about it as a time/water saver
21:43 flatr0ze you know the faucets with IR sensors in public restrooms?
21:43 flatr0ze this is the same idea
21:43 flatr0ze the scanner works, but the tough part is the robotics
21:44 flatr0ze the stepper I got is not able to rotate this thing well enough
21:44 flatr0ze only @ very low speed
21:44 Tom_itx i'd be concerned about fine china in that thing
21:45 flatr0ze people won't be putting expensive things in there, just like in a usual dishwasher... those people wash by hand
21:45 Tom_itx how do you know this?
21:45 flatr0ze I need to make 3 rotatioins in 1.5 seconds, then go back... during first 3 rotations it makes a spiral with a high-pressure nozzle
21:45 flatr0ze well I've seen what people do with wine glasses and china -- they treat them very well and afraid to put in things with moving parts
21:46 Tom_itx wash my gravy bowl
21:46 Tom_itx what about odd shaped dishes?
21:47 flatr0ze it will wash them anyway, but not sure it'll be efficient
21:47 flatr0ze it's a digital dishwasher
21:47 Tom_itx i'm just throwing ideas out there
21:47 flatr0ze so we could always create programs for different ones
21:47 flatr0ze and it's extremely hard to make the mechanism... the scanner was easy, I got done with it in 2 days
21:49 flatr0ze for the robotics I tried the CNC approach, but it was extremely slow
21:49 flatr0ze it's 18"x18"x6" of thickness
21:50 flatr0ze -1" or -2" from each side due to mechanics
21:50 flatr0ze it's a cool project and it's a shame I almost failed it because of the slow speed and low power
21:50 Tom_itx what about the silverware?
21:50 flatr0ze not even sure using steppers is a good idea... but that's the only way scanner would make a difference
21:51 flatr0ze Tom_itx: for silverware it's the same thing: different programs
21:51 flatr0ze we will have a separate box for that in the bottom, I believe
22:01 flatr0ze so now I'm not even sure I'm heading in the right direction with all this, since the motors keep getting bigger, and it's still not enough torque at that speed to rotate the whole construction and carry the water hose