#robotics Logs

Nov 24 2012

05:03 chris_99 potentially
05:03 chris_99 you could put a diode to prevent damage
08:15 Skwint "potentially" damaged - good one :p
08:17 chris_99 well how do you know for sure
08:17 chris_99 the reg. may have an inbuilt diode
09:15 Skwint I was making it into a "potential" joke about the voltage - I'm sorry :(
09:23 chris_99 ah sorry :(
09:43 Centauri this could be interesting, if its not too expensive: http://phys.org/news/2012-11-low-cost-finger-nail-sized-radar.html
10:00 Skwint manufactured on an industrial scale, each complete miniature radar would cost around one euro
10:00 Skwint would certainly replace those damn IR things I have atm :p
10:03 Centauri LOL - I was wondering about the width of the beam, and associated pattern
10:04 Centauri or if there is a way to bring it into a tighter focus.. like a small feedhorn or something
10:20 chris_99 don't they use something like that atm in police radars
10:20 chris_99 oh not 120GHz though heh
10:28 Centauri yeah, looks like police radar is far low X and K bands (8-12 GHz and 18-26GHz)
10:28 chris_99 aha
10:30 Centauri what I used to work on was lower yet: http://en.wikipedia.org/wiki/AN/TRC-97
10:31 Centauri its funny, that picture was the site I used to be at.. they even referent the 602nd TCS unit, which was my unit in the 80s
11:39 rue_mohr wow, I got a refund from one of the sellers in china, I had to look thru 4 different identities to work out what the refund was for
17:15 Tom_itx rue_mohr, what did you get done today?
18:14 rue_mohr heh a bristlebot for the cats
18:14 rue_mohr no
18:14 rue_mohr I cut up some of the logs we got from the beach
18:14 rue_mohr split some of what I cut
18:15 Tom_itx do you know how to write special characters to lcd?
18:15 rue_mohr robotics, we worked on the air system for the rubix cube gripper
18:15 rue_mohr special characters that are of codes 128+ or of home brew creation
18:16 Tom_itx the degree symbol and their thermometer symbol
18:16 Tom_itx they have them mapped in code
18:16 rue_mohr there are a variety of types of roms with different extended codes
18:16 Tom_itx but it doesn't display right on mine
18:16 Tom_itx i wired up a 20x4 last night
18:16 rue_mohr have you seen my proper 447780 datasheet
18:16 rue_mohr !assist datasheets
18:16 tobbor Possibly http://eds.dyndns.org/~ircjunk/datasheets
18:16 Tom_itx i have a data sheet
18:16 rue_mohr its the proper one
18:16 Tom_itx for it
18:17 rue_mohr you have a stupid sheet I'm sure
18:17 rue_mohr this is the full, real datasheet
18:17 Tom_itx i'm not so sure of that
18:17 rue_mohr hard to find
18:17 rue_mohr http://eds.dyndns.org/~ircjunk/datasheets/hd44780.pdf
18:17 rue_mohr that sheet
18:18 Tom_itx mm apparently i didn't put it up on my site
18:20 Tom_itx ahh yeah here it is: http://tom-itx.dyndns.org:81/~webpage/pdf/hd44780.pdf
18:27 rue_mohr is that the same as mine or is that one of the 20000000 lame ones?
18:27 rue_mohr :) looks like the same one
18:28 rue_mohr 0xDF isn't the degree symbol for you?
18:28 rue_mohr what do you get?
18:28 rue_mohr beta?
18:28 Tom_itx a zero
18:29 rue_mohr try 0xB0
18:30 Tom_itx they mapped it in software
18:30 Tom_itx with a bitmap
18:30 Tom_itx and write it to the display as such
18:30 rue_mohr so what are you asking
18:30 Tom_itx in a couple vacant spots
18:31 rue_mohr there are 16 free spaces
18:31 Tom_itx i just couldn't figure out why mine wouldn't display it
18:31 rue_mohr er 8
18:32 rue_mohr maybe they set it up as a custom character and then try to use the one in rom
18:32 Tom_itx i'm tempted to get a newer display anyway
18:32 Tom_itx i'm not doing anything with it right now anyway, just wanted something to do
18:32 rue_mohr most often trying to mod other peoples work is a pain, cause they just hacked it off a guy who hacked it off someone who hacked...
18:33 rue_mohr everything is done wrong and half the code does nothing cuase other code redoes its work
18:34 rue_mohr can you make a setup to read data from the display?
18:34 Tom_itx i dunno
18:34 Tom_itx not sure how
18:37 rue_mohr I wonder how you query the character rom type
18:37 rue_mohr I'v never looked, but its not here
18:39 rue_mohr I dont think you can
18:45 rue_mohr Tom_itx, can you see the part number on the chip?
18:45 rue_mohr HD44780UB**
18:46 rue_mohr where ** is A00 or A02
18:46 rue_mohr or similar
18:46 rue_mohr I'm curious, I'v never used characters out of the std ascii
18:47 Tom_itx just a sec
18:47 Tom_itx pull up the lcd file of theirs
18:47 Tom_itx you can see the maps
18:47 rue_mohr yes
18:48 Tom_itx HD44780A00
18:48 rue_mohr ok
18:48 Tom_itx same on the 2nd one
18:48 rue_mohr 0xDF is degree then
18:48 Tom_itx same on the 3rd one
18:48 rue_mohr no need for custom characters
18:49 Tom_itx i'm not sure but what it may have displayed correct once or twice though
18:49 Tom_itx what about the '/'
18:49 rue_mohr I should go put limit switches on my machine
18:49 Tom_itx between their temperature displays
18:49 Tom_itx you gonna play tonight?
18:50 rue_mohr 0x2f
18:50 rue_mohr yea
18:50 Tom_itx i've got a couple oddball ones i may try too
18:50 rue_mohr its not a long trip to the shop
18:50 Tom_itx lemme grab one
18:50 rue_mohr might be going for the 10x22 lathe
18:50 rue_mohr I'v worked on a myford that was 7x20 and its a fine size
18:50 Tom_itx is that the bigger one?
18:50 rue_mohr yea
18:51 Tom_itx i would
18:51 rue_mohr the small one was 7x12
18:51 Tom_itx if i had to choose and could
18:51 rue_mohr almost a fewlers
18:51 rue_mohr jewlers
18:51 Tom_itx don't bother
18:51 Tom_itx these others have dots on the chips but are datavision lcds
18:51 Tom_itx the timing is a bit different on them
18:52 Tom_itx i think i'll plug one in and try it
18:52 Tom_itx they're brand new
18:52 Tom_itx i traded someting for them several years back
18:52 rue_mohr the target is a 10x22 with parting tool, knurling tool, live centre, 1/2" drill chuck, and some carbide straight and left holders
18:53 rue_mohr comes with 3 and 4jaw
18:53 rue_mohr and steady rests
18:53 Tom_itx you probably won't use the steady rest
18:53 Tom_itx get some boreing bars
18:53 Tom_itx a set
18:53 Tom_itx and raw tooling
18:53 Tom_itx whatever size fits the tool post
18:53 rue_mohr I dont really expect to do boring
18:53 Tom_itx i can get it here if you can't and send it
18:53 rue_mohr and I could just make one
18:54 Tom_itx you will do boreing
18:54 Tom_itx that's basically what i have for mine
18:54 Tom_itx get a couple dial indicators one 2" to mount on the slide
18:55 rue_mohr I'm choosing where to economize
18:56 rue_mohr knurler is only $20 !?
18:56 Tom_itx http://tom-itx.dyndns.org:81/~webpage/sumo_files/lathe3.jpg
18:56 Tom_itx like that
18:56 Tom_itx mine is adjustable
18:56 rue_mohr is that a myford?
18:56 Tom_itx so you can tell how much you move from side to side
18:56 Tom_itx i dunno
18:56 Tom_itx it wasn't that much
18:56 Tom_itx the lathe is an old sears atlas
18:57 Tom_itx nearly an antique now
18:57 rue_mohr what isn't
18:57 Tom_itx but i do stuff with it still
18:57 rue_mohr the machine shop book I pullout out to looking something in robotics today is a 1947 book
18:57 rue_mohr and thats the reprint!
18:57 Tom_itx if you're not sure i can tell you if you'll use something or not
18:58 rue_mohr I can make a boring bar if I need one
18:58 Tom_itx carbide tip
18:58 Tom_itx get all carbide if you can
18:58 rue_mohr the chuck only has a 3/4" throat, cant bore much there
18:58 Tom_itx except the tooling you grind
18:58 Tom_itx about the same as mine
18:58 rue_mohr I have a bunch of HSS stock
18:59 Tom_itx you can bore into stuff like that tube in the pic
18:59 Tom_itx that about maxed out what it will do
18:59 rue_mohr I'm gonna call that on demand
18:59 Tom_itx like 3/4" drills etc
18:59 rue_mohr I dont tend to do stuff like that, it usually results in metal flying across the room
18:59 Tom_itx i get those on demand too but i have a ?115 piece drill set
19:00 Tom_itx number letter fraction
19:00 Tom_itx and get metric as needed
19:00 Tom_itx i get reamers surplus
19:00 Tom_itx cheap
19:00 rue_mohr :) so far I have a standard 1/16 - 1/2" imperial set, a small metric set (1mm - 10mm) and a letter/number set
19:01 Tom_itx i got one of those too for the drillpress
19:01 Tom_itx i keep the big set sharp for 'good' work
19:01 Tom_itx not for every day
19:01 rue_mohr wow, I took friday off,
19:01 rue_mohr I'm REALLY awake
19:01 Tom_itx i didn't
19:01 rue_mohr maybe not awake as much as lucid
19:01 rue_mohr which is nice
19:02 rue_mohr I'ma go play in shop
19:02 Tom_itx is 1..14 the same pinout on lcds?
19:02 Tom_itx 15 16 are backlight?
19:02 Tom_itx this one has the 2 extra pins
19:03 Tom_itx aww crap the pins are too big to fit my socket
19:05 Tom_itx dammit
19:06 Tom_itx yet another cable...
19:09 rue_shop3 :)
19:10 rue_shop3 I know the feeling, all my avr carrier boards use 10 pin programming headers, accept for this one set
19:10 Tom_itx i found one i can patch fairly quick
19:10 rue_shop3 ...
19:10 rue_shop3 :)
19:10 Tom_itx pretty sure i won't be using it. it was for a 68hc11
19:23 Tom_itx ok it displays right on the datavision
19:23 Tom_itx but i need more bias, it's too dim to see
19:29 rue_shop3 if you ground the bias line what do you get
19:29 rue_shop3 soem fothe displays are 0-5 and some are 0-> -3
19:30 rue_shop3 if you go the wrong way, I thin things burn out
19:31 Tom_itx this needs negative bias
19:31 Tom_itx like -10v
19:32 rue_shop3 !!!!
19:32 Tom_itx it's probably why he traded me
19:32 rue_shop3 I'v never seen soemthing need that far
19:33 Tom_itx i'll verify it once i get a jumper wire
19:33 rue_shop3 max232 to the rescue
19:34 rue_shop3 shall I spend $40 on a wireless video link to play with some ROV's?
19:34 rue_shop3 I'v never been able to work out a channel 3 amp for the modulators I have
19:35 Tom_itx that was no load
19:35 Tom_itx hooked up it's -2.4
19:35 Tom_itx so you were right
19:35 Tom_itx i can't get rid of the squares entirely though
19:36 rue_shop3 thats uaulyl overbias
19:36 rue_shop3 ?
19:37 Tom_itx i turn the pot and that's the best i can get
19:37 rue_shop3 ah
19:37 Tom_itx gnd does little
19:37 rue_shop3 I'm gonna puts thru the boxes
19:37 Tom_itx those other displays were better
19:38 Tom_itx i wonder why the other ones won't display the characters
19:39 Tom_itx i don't wanna wiggle this too much, i got bare wires runnin everywhere
21:08 eadthem http://www.ebay.com/itm/6V-8RPM-Torque-Gear-Box-Motor-New-/110873949529?pt=LH_DefaultDomain_0&hash=item19d09a3559
21:08 eadthem what kind of torqe you think one could expect from a gearmotor like that
21:08 eadthem 8RPM output 80mA 6V input
21:09 Tom_itx for $8 you could find out
21:09 Tom_itx probably plenty for your project
21:10 eadthem probably
21:10 Tom_itx get a spare in case you ever need to replace it
21:29 eadthem k ya
21:29 eadthem my orignal plan will work
21:31 Centauri it says about halfway down 3.0Kg / cm
21:32 eadthem it did?
21:33 eadthem 6 pounds way more than enough
21:34 eadthem https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=5378&GroupID=218
21:35 eadthem gonna cut a slot for the deadbolt knob in that
21:38 Centauri 3 kg cm = 41.66 oz in = 0.2169 ft lbs
21:40 eadthem well going to be a 10 tooth pully to 120 tooth pully
21:40 eadthem so that will bring it up over a foot pound
21:40 eadthem still shuld be more than enough
21:40 Centauri ;)
21:41 Centauri I had to find 2 different converters to get to ft lbs lol - but hey, it works
21:42 eadthem ya tbh 6lb cm tells me what i need
21:42 eadthem iirc at 4cm it would be about 1.5 lb
21:50 eadthem neoprine or polyuriathane?
21:50 eadthem and polyester, kevlar, or fiberglass cording
21:50 eadthem for the belt
22:06 Centauri eadthem: what ya making?
22:07 eadthem door lock
22:07 Centauri ahh ok