#robotics Logs

May 20 2013

00:00 shuggans so java and c++ look familiar
00:00 shuggans syntax wise
00:02 shuggans what do you guys think we should do for treads?
00:02 orlok shuggans: what you have right now is reppy close sorta
00:02 orlok instructables.com down?
00:03 shuggans He just made links with the brackets on them so we could attack whatever to that
00:03 orlok http://letsmakerobots.com/node/21908
00:04 orlok shuggans: that?
00:05 shuggans yes - I wonder if he can make 2 more chains like he has now and extend an extra sprocket 4" - 6" off the existing ones..
00:06 shuggans anyways - off to do some wiring... >:)
00:07 Jak_o_Android Remind me. Divides, white stripe = arrowhead?
00:07 RifRaf huh?
00:08 Jak_o_Android Diodes
00:08 RifRaf stripe goes to negative i believe
00:09 Jak_o_Android Brain fade, what side of the arrowhead2in the circuit symbol Is that?
00:11 RifRaf the line http://upload.wikimedia.org/wikipedia/commons/thumb/8/83/Diode_pinout_en_fr.svg/640px-Diode_pinout_en_fr.svg.png
00:13 Jak_o_Android Thanks
00:23 MrCurious shuggans: cant you use mono on linux to simulate .net?
01:49 Jak_o_Android H bridge provisionally all soldered up, excluding capacitors and voltage supplies
02:00 rue_house remember to test it with a small value fuse
02:01 rue_house catch any faults without lots of fault current
02:01 rue_house ----|>|-----
02:01 rue_house anode cathode
02:02 rue_house ^ end with stripe
02:06 Jak_o_Shadows Oh, i'll definitely be double-checking all the connections and stuff now
02:07 Jak_o_Shadows Silly thing is, it's a 20 minute walk (or drive, to a different store) to get the two capacitors I need
02:09 orlok I didnt know they made DB37 connectors. Until i accidentally bought one
02:10 rue_house has anyone ever heard of a old price of software called corefast backup?
02:12 orlok fuck i cant wait to get my phone back
02:13 orlok need tot ake some pictures of the board i put together on the weekend
02:13 orlok no jumper wires to bridge anything
02:13 orlok no point to point wires at all, all done on the underside too
02:14 orlok and once i solder up the 4 connections i missed, i think it should work too
02:58 Jak_o_Shadows A couple of small short-circuits, and I need to cut some traces, but the h-bride seems fine I think.
03:13 Triffid_Hunter Jak_o_Shadows: tip: put a light bulb in series with your supply. if there's a fault, it'll light up and hopefully stop things from burning straight away
03:14 Jak_o_Shadows By too much current going through it? I don't see why that indicates something's wrong
03:15 Triffid_Hunter Jak_o_Shadows: yeah too much current. the light bulb gives a visual indication of overcurrent, as well as limiting the current
03:16 Jak_o_Shadows Ah. A torch bulb?
03:16 Triffid_Hunter Jak_o_Shadows: light bulbs are very interesting from an electrical perspective.. they have a very low resistance when cold, which increases by some 6x as they heat up
03:16 Triffid_Hunter Jak_o_Shadows: for a h-bridge I'd be using a car tail-light
03:18 theBear as far as tuning such a setup (it's kinda a black art picking the 'right' bulb) you want it so the bulb quickly starts glowing at around the max safe current
03:18 theBear it's a good trick, a globe is just a tiny wire until it heats up, magic !
03:19 Triffid_Hunter I was using a 50w downlight as a test load for my h-bridge, was surprised that I could hear the PWM coming from that bulb more loudly than it did from the motor!
03:20 Jak_o_Shadows As I don't have too much access to that, I think i'll pass on that, and pray that it works.
03:20 Jak_o_Shadows If all else fails, I'll use a DPDT switch and a servo
03:20 Triffid_Hunter Jak_o_Shadows: at the very least use a thin piece of copper, maybe 2-3 strands from one of your wires as a fuse
03:20 theBear hehe yeah, bulbs tend to have a resonant freq, but in general downlight bulbs seem to be pretty 'loud' ... suppose they got a lotta curled up filiament with little support usually
03:21 theBear generally for fusing i start with only a single strand unless it's TINY wire, look at a handful of fuses, they're ALL pretty thin
03:21 Jak_o_Shadows Yeah, I made sure not to use single-core breadboard wire for connecting between things that might actually carry current.
03:22 theBear also, one of these days i'm gonna get around to making a little 'standalone'/series insertable current limiter, something like a 317 or just a transistor and a pot and maybe some resistor
03:22 RifRaf Triffid_Hunter, fixed the stepper motor mounts, much better, will try post you a set tomorrow arvo
03:22 theBear lol, 24 gauge or similar 'breadboard wire' would make a pretty darned high current fuse
03:23 theBear well, at least a few amps
03:23 Jak_o_Shadows Yeah. Was saying that I didn't use that for important stuff, mostly because current limits and you get breaks damn easy when you flex it
03:24 RifRaf Triffid_Hunter, no obstructions now http://imagebin.org/258300
03:26 Jak_o_Shadows oooh, cool
03:28 RifRaf Jak_o_Shadows, am starting assembly for real finally, hopefully in a few nights will have a new printer
03:31 Jak_o_Shadows coool! Have you priced filament and such?
03:32 RifRaf nope just got a few meters to test with for now, hrm dunno where i put that
03:33 RifRaf and the hot end is another part i still need, but that gives me time to get the mechanical side working first
03:44 Triffid_Hunter RifRaf: shannon should have, or be receiving some hotends soon enough
03:45 RifRaf yep he said would be soon
03:46 Triffid_Hunter Jak_o_Shadows: we have 3mm ABS in our shop for $60 per 300m/2.5kg and we can get some of the highest quality PLA in the world from new zealand for about $35/kg
03:58 Jak_o_Shadows Cool. I always want to compare to shapeways, so how much per solid cm3 does that make it?
04:25 Triffid_Hunter Jak_o_Shadows: hm, 2.8c/cm^3 if I did my math right
04:25 Triffid_Hunter Jak_o_Shadows: the cost of the plastic is relatively insignificant, most of what you're paying for is operator and machine time when you buy printed parts
04:26 Jak_o_Shadows apparently
04:26 Jak_o_Shadows Thanks, never actually got a cost like that before
04:26 Jak_o_Shadows Never looked that hard, but now I want a 3D printer more
04:28 SorcererX on Shapeways metal costs a lot more than plastic though
04:40 Triffid_Hunter Jak_o_Shadows: all the plastic parts for a prusa i2 total about $15 in plastic and I think the i3 uses less
04:49 Jak_o_Shadows Hmm. I think the only main obstacle to me getting a 3D printer is how I cannot fabricate the frame. Everything else (apart from extruder, bed, controller) I Probably could get close enough from a couple of old printers I have.
04:50 e_shop3 hands Jak_o_Shadows a piece of wood and a hac
04:51 Jak_o_Shadows Haha. Bad enough hacking the slide and stuff together from second-hand printer parts, let alone making the frame with my current materials/parts.
04:51 Jak_o_Shadows Although, i'm probably just some decent drill bits away really
05:04 RifRaf Jak_o_Shadows, you are in au are you not?
05:05 Jak_o_Shadows yeah.
05:05 RifRaf well very soon will have a good frame to sell
05:06 RifRaf http://imagebin.org/258302 this is mine so far
05:07 theBear i haven't looked into it too much for 3d printing, but recently for lighter 'cnc' style setups i've been fond of a one axis each way setup, one axis moves the bed, and another moves the head... might be worth considering, makes things much simpler not needing to mount a moving axis on a moving axis
05:08 theBear suppose i didn't mention the 3rd axis, but you can guess where it would go :)
05:08 theBear the example i saw was a laser etcher, so there was no 3rd
05:08 RifRaf theBear, thats what the one i am making is like
05:09 RifRaf has 2 motors to go up and down for the z
05:09 theBear oooh, cool, i only seen bits and pieces so far, and been looking at how you made them rather than what they are :)
05:10 RifRaf that last link is the most together, this is more of the last frame http://imagebin.org/258028
05:10 theBear i think i like the idea even for bigger/heavier (actual cutting kinda tool) cnc too, means the axis can be more similar physically, even the same perhaps, rather than needing one huge one to support the other one (or two)
05:11 theBear hmmm, i think i see it, that bit sits in that orientation and the vertical axis rails where the big holes are ?
05:11 RifRaf yep can see meself wanting to make a cutting tool cnc after this
05:12 theBear with your current access to real fab tools i imagine you could make a kickass one... you may claim to have little skill <grin> but you're pretty damned good, specially in the mechanical side of things
05:13 RifRaf i have not added the x axis or left to right yet, and those two steppers with drive the up/down, and the Y is the bed going forwards and backwards
05:14 RifRaf will be several nights work, and don't think i'll get much more done today
05:17 theBear i finally cutup the old dolphin (6v lantern torch) reflector i put aside thisafternoon, i'm pretty pleased with that :)
05:18 RifRaf got the coolest new battery screwdriver the other day, lithium batt, led to see and a gyro inbiult to know wat way you wanna go and how fast
05:19 RifRaf you just put pressure on the end and move your hand a bit and off it goes, reverse the battery and is a balancing robot basically
05:19 theBear the leds bug me most of the time, unless i'm you know, crawling under something dark and just need to get a couple screws done in a hurry, but i do like cool minidrill/batt screwdrivers
05:19 theBear hmmm, pressure eh ? i like that
05:20 RifRaf reverse the motor i mean
05:20 RifRaf yeah the end is a big button, and the speed direction if controlled by how much you then turn it
05:21 RifRaf so locks the gyro into watever position pressure is first applied
05:21 RifRaf after some practice is awesome to use
05:21 Jak_o_Shadows well, dammit
05:22 RifRaf http://www.blackanddecker.com/power-tools/bdcs40g.aspx
05:22 Jak_o_Shadows apparently both pins need to be digital read for some reason. Or the other pins I have here are borked.
05:22 Jak_o_Shadows analog read*
05:23 theBear both pins what ?
05:25 Jak_o_Shadows Trying to use 3 ultrasonic sensors. https://github.com/energia/Energia/wiki/images/LaunchPad%20MSP430G2553-v1.4.jpg Need a 10uS output on one pin, and pulsein arduino function on the other. works with 1_3 and 1_4, and 1_6 and 1_7
05:27 theBear hmmm, don't suppose you know what a pulsein is in non-arduino language ?
05:28 Jak_o_Shadows Nope. Records a 40ish kHz pulse. and it's working when I use a digital only pin to output, and an analogread to input\
05:30 Jak_o_Shadows time to move lots of pins around now.
05:38 Jak_o_Shadows Note to self: Plug uC in before trying to program it
05:47 rue_house Jak_o_Android, no wireless, zero power programming support?
05:50 Jak_o_Shadows Not for $4.30
05:50 rue_house how about $2.10
05:52 Jak_o_Shadows lol
05:52 rue_house who wants to elp me ponder an addition to a motor control protocol?
05:53 rue_house http://paste.debian.net/5306/
05:53 rue_house this is the protocol
05:53 rue_house but for steppers I need to add a mechanism that that controller can query the state of a zero sensor
05:54 rue_house ooh actually,
05:54 rue_house it looks like I could just poke it in as a new command...
05:55 Jak_o_Shadows My control system for serial control of my robot is bad. It's [Control What (t, s, m)][Number of thing][value (if applicable)] . You know, not with [], just next to each other
05:56 rue_house this is just a protocol for a serial bus for controlling servos
05:56 rue_house I'm trying to apply it to a stepper controller and I dont think its going to work
05:58 rue_house my protocol allows for synchronous movement and polling for large servo buses
05:58 rue_house I tried to keep it as tight as I could for transfer efficiency
06:00 rue_house yea, I think thats a level up
06:00 rue_house k
06:34 Jak_o_Shadows I copied and pasted some pin mode initialization code, and never changed it correct.....
11:27 Tom_L http://www.electronicproducts.com/Computer_Systems/Servers/International_Space_Station_makes_switch_from_Windows_8_to_Linux.aspx
11:27 Tom_L heh
12:58 rue_bed heh
15:49 rue_bed Hello Worl
15:51 RifRaf d
16:14 rue_house I got the stepper controller baord workign last night
16:14 rue_house have to wire the rest of the output drivers
16:14 rue_house and build the input system
16:16 rue_house the number 6 in base 6 is 10
16:24 RifRaf looks a bit windy at toms place
16:56 Tom_itx not atm
17:05 rue_house tom... was that a house that just rolled down the steet out you window?
17:06 Tom_itx nice sunny day here
21:09 MrCurious new outdoor kittens have appeared. and we still have inventory left over from last year!
21:10 Tom_itx better have a kitty sale
21:10 theBear heh... last night the local kitty came to visit and napped in the spareroom/workshop for a few hours :)
21:11 MrCurious we have too many already. the idea of MOAR! gets a resounding NO!
21:11 Tom_itx ok i got my usb driver issues worked out
21:11 Tom_itx had to manually remove a couple .dll files and then it would reinstall and recognize the device
21:11 MrCurious so they used windows on the space station
21:11 MrCurious the horizon is blue
21:11 MrCurious and my screen is too
21:12 Tom_itx you gonna buy a one way ticket to mars?
21:12 MrCurious wonder if they have to reboot the space station every few days :D
21:12 MrCurious Tom_itx: playing off your news link from 9 hours ago
21:12 Tom_itx not since they went to ubuntu
21:12 Tom_itx i know
21:13 Tom_itx i'll give ya another one
21:13 MrCurious "sir! i am showing this as the third space station you have activated. you will need to purchase a new license"
21:13 Tom_L HARTING adds a slew of FREE samples to Electronic Products' Sample Center
21:13 Tom_L http://www.electronicproducts.com/Sample_Center_Landing_Page.aspx
21:14 MrCurious whoa! this tornado damage is intense
21:14 Tom_L at least 51 dead
21:15 Tom_L K-3rd
21:15 FreezingCold Tom_L: Kids?
21:15 FreezingCold What's the total count?
21:15 Tom_L dunno if all 51 were but some
21:15 Tom_L i dunno right now
21:15 FreezingCold Wow, that's horrible
21:15 Tom_L hit a elementary and leveled it
21:16 Tom_L very high winds
21:16 FreezingCold Would hiding in your basement even help at that stage?
21:16 Tom_L 300+ mph
21:16 MrCurious the damage... cannot look away
21:16 FreezingCold glad I don't have any natural disasters where I live
21:17 MrCurious everywhere on the planet has them
21:17 FreezingCold well, we have ice storms but those normally don't kill anyone directly.
21:18 MrCurious no tornados?
21:18 MrCurious flood
21:18 FreezingCold nope
21:18 MrCurious lightening
21:18 FreezingCold unlikely to set anything on fire
21:18 FreezingCold it's always damp
21:18 MrCurious you live in a volcano island hide out or something?
21:18 MrCurious mold storms!
21:18 MrCurious they rolled across england a few years back
21:18 FreezingCold or you know, Ottawa, Canada :D
21:18 MrCurious made it hard to brie
21:19 FreezingCold we had the great ice storm of 98
21:20 FreezingCold oh god I feel too canadian saying that >_<
21:20 FreezingCold I'm sitting here right now at 65F
21:25 Tom_itx ice?
21:26 Tom_itx http://tom-itx.dyndns.org:81/~webpage/temp/ice/14.jpg
21:28 MrCurious i heard manitoba has ice tusnami's
21:28 Tom_itx http://tom-itx.dyndns.org:81/~webpage/temp/hail/hail5.jpg
21:42 Tom_itx http://tom-itx.dyndns.org:81/~webpage/temp/ice/12.jpg
21:42 Tom_itx not snow
22:21 theBear rue/anyone else with a good memory, was it you/rue that did a vfd display as valve for an experiment a few years back ? and if so, remember roughly what useful gain you were able to get
23:23 rue_shop3 I'v done vfd
23:23 rue_shop3 whats up?
23:24 theBear we were casually chatting about that kinda stuff in the electronics channel and someone asked the old 'can they be abused as a tube, for novelty reasons' question, and if you could get gain >1, and i had a feeling you had both done it, and had a number maybe in the 5-15 area
23:25 rue_shop3 yes, vfd's can be used as tubes, there is a youtube video
23:25 theBear i don't want no stinkin youtube, course if you told me i'd believe without proof :)
23:43 MrCurious today is all full of WIN!
23:49 MrCurious interesting http://users.humboldt.edu/mstephens/hate/hate_map.html