#robotics Logs

Aug 28 2014

01:01 mugenzebra that's awesome
01:37 rue_shop3 wow, that component tester is awesome
01:37 rue_shop3 I just ran like 300 "transistors" thru it
01:38 rue_shop3 there were PNP, NPN, complete burnouts, diode arrays, jfets! SCRS! and triacs!
01:38 rue_shop3 I have a sweeeeeeet new pile of parts to play with that I didn't know I had
01:38 rue_shop3 AND I totally now know how to read the small ceramic caps
01:39 rue_shop3 if they say "330" on them, its definitly 330pf, not 33*10^0
01:39 Mr_Sheesh WHere did you get that from, rue_shop3?
01:39 rue_shop3 and such 57 is not 5*10^7
01:39 rue_shop3 china
01:39 Mr_Sheesh How much was it/
01:39 Mr_Sheesh ? not /
01:40 rue_shop3 not much , like $13
01:40 Mr_Sheesh Not bad :)
01:40 Mr_Sheesh Makes me tempted to get one
01:40 rue_shop3 http://www.ebay.com/itm/Mega328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter-MOS-PNP-NPN-L-C-R-/251623648507?pt=LH_DefaultDomain_0&hash=item3a95f02cfb
01:40 rue_shop3 thats better than the one I got
01:41 rue_shop3 I got it to filter PNP/NPN, but also to read sub 1uF caps (my meter cant) and sub 1H inductors (my meter cant)
01:41 rue_shop3 meter = multimeter
01:41 rue_shop3 this tester does it great
01:42 rue_shop3 I'm surprised tho how many transisotrs that I'd done prototyping with were burned out!
01:42 Mr_Sheesh Interesting. Good to know if they're DOA!
01:42 rue_shop3 there were a few transitors with gains of like, 5, after a while I started throwing them out
01:43 Mr_Sheesh 5 is OK for TO220 or TO3 power transistors but not so much for small signal BJTs :P
01:43 rue_shop3 one of the parts stacking up in the fail pile is marked
01:43 rue_shop3 UA43
01:43 rue_shop3 1AWC
01:44 rue_shop3 which I think is UA431, which I think is a knockoff of TL431
01:45 rue_shop3 :/ I think all the ones listed on ebay are better than the one I got
01:45 rue_shop3 ahh whatever
01:54 Mr_Sheesh Do the parts that say 5 gain seem to verify that if you test their gain yourself?
02:13 rue_shop3 not gonna bother
02:14 rue_shop3 from the tests I'v done on it, its pretty close
02:14 rue_shop3 most of the pn2222 were around 150 to 220 gain, which is about right
02:14 rue_shop3 ooo
02:14 rue_shop3 a part it couldn't identify turns out to be hall sensors
02:15 rue_shop3 oo linear output...
02:18 rue_shop3 wow, that totally cleans up my transistors misc bins
02:47 rue_shop3 huh, I have PUTs UJTs and SCRs mixed up in drawrs...
02:54 rue_shop3 wow, I have lots of UJTs
02:54 rue_shop3 I dont know how long I wanted some for, to make oscillators and flashers
02:55 GargantuaSauce_ the 2-transistor astable multivibrator / flipflop is my goto simple oscillator for stuff like that
02:55 GargantuaSauce_ love that design
02:56 GargantuaSauce_ the symmetry is so pleasing
02:56 GargantuaSauce_ it's also the first nontrivial circuit i understood/characterized
03:28 rue_more can you get one up to 250Khz tho :)
03:28 rue_more I was sad when I found out I couldn't
03:28 rue_more wanted to use it for a simple power supply
03:30 GargantuaSauce_ ....can you get a ujt one that high?
03:31 rue_more I think I did
03:31 GargantuaSauce_ that is pretty surprisng
03:31 GargantuaSauce_ i'd just use a ring oscillator
03:32 rue_more I needed two opposite phases of 50% duty (back when)
03:33 rue_more the latest attempt was to make a minimal osc for pwm
03:34 rue_more but then I decided to try a digital pulse to operate a D latch, and used a 555
03:34 rue_more but that didn't really work out
03:34 rue_more I think my bench supply is going to be a linear regulator with a pwm output driver
03:34 GargantuaSauce_ yeah they work really well going 2 orders of magnitude slower, lol
03:34 rue_more which makes the voltage and/or current control more complex
03:35 GargantuaSauce_ that's....special
03:35 rue_more http://www.diy-electronic-projects.com/projects/71/bigs/0_50v.jpg
03:35 rue_more there is the schematic that uses the ... 10th chip, ever designed....
03:36 rue_more off the top of my head, I know of no chip with a part number lower than LM10
03:36 rue_more tho, I'm burning with curiosity over what the LM1 was
03:40 GargantuaSauce_ hehe that design is interesting
03:40 GargantuaSauce_ wonder what happens if you sink current into the + rail
03:45 rue_more oh I remmeber the problem
03:45 rue_more the schmitt on the voltage detector was .2V, so, that was the output ripple
03:45 rue_more if I'm gonna build a power supply, its NOT gonna have .2V output ripple
03:45 rue_more that was the lm393
03:46 rue_more as a comparitor
03:46 rue_more so I need to work out a TL431 circuit
03:46 rue_more I'm not sure what the average ripple on a computer smps is tho
03:47 rue_more generally, pumping power into a power supply is a bad thing
03:51 GargantuaSauce_ a design should be able to tolerate it though, to like a significant fraction of the output rating i think
03:51 GargantuaSauce_ i think typical pc ps ripple is like 5%
03:52 GargantuaSauce_ maybe a little less
03:53 Tom_itx so, what are we working on this fine evening?
03:55 GargantuaSauce_ not a lot. i'm still half tipsy from going out earlier and i woke up after an hour of sleep due to thinking about image processing algorithms for diffraction microscopy
03:55 rue_more ah right, the problem with using a tl431 is that I have to sink it 2.5V under the ground rail
03:56 GargantuaSauce_ i have mcp602 for rail-rail stuff
03:56 GargantuaSauce_ they are pretty cheap
03:56 rue_more the tl431 is a votlage detector
03:56 GargantuaSauce_ oh a shunt reference
03:56 rue_more but its thres is 2.5V, and i need to do 0-30V, so I'd have to sink it 2.5V under the ground to get 0
03:56 rue_more *atleast*
03:57 rue_more maybe I should see if it solves the ripple problem first
03:57 rue_more hmm, I think .05V ripple is an ok target
03:57 GargantuaSauce_ yeah certainly
03:57 rue_more its a bench supply
03:58 rue_more tho I'm leaning towards continious pwm controlled by a proportionate analog error amp tho
03:58 rue_more ...
03:58 GargantuaSauce_ sooo an smps
03:58 GargantuaSauce_ make up your mind!
03:59 rue_more I have a great pwm circuit, but it dosn't, with the parts I'v ever made it from, do 250-500Khz
03:59 GargantuaSauce_ why do you need it that fast anyway
03:59 rue_more what freq do you thik I should use? 20Khz, 40Khz?
03:59 GargantuaSauce_ 40 would be fine i'm sure
04:00 GargantuaSauce_ well out of audible
04:00 rue_more hmm
04:00 GargantuaSauce_ you'll need a bigger inductor but i'm sure you can make that happen
04:00 rue_more the pwoer supply has lots of room
04:01 rue_more http://hackaday.io/project/296-Bench-power-supply
04:02 GargantuaSauce_ actually you should figure out the switching freq of the master supply brick
04:02 GargantuaSauce_ and divide that by an integer i guess?
04:02 rue_more I'm not too worried about synchonizing them, I'm sure the output caps on it are fine...
04:03 GargantuaSauce_ heheheh
04:03 GargantuaSauce_ mine squeals like a stuck pig when i use a lot of servos and another smps in the middle
04:04 rue_more what do you have?
04:04 GargantuaSauce_ 12v magic brick like that
04:04 GargantuaSauce_ actually three of them and they're all slightly different
04:04 rue_more ah
04:05 rue_more it didn't occur to me origionally that the chinese regulator moddules would sample their current from their - side
04:05 GargantuaSauce_ yeah i remember you mentioning some...issues with that
04:06 rue_more so it blew up pretty quick when I shorted the + of one into the - of the other
04:07 rue_more the digital controls are nice
04:07 rue_more the fine and course adjustment capability worked nice
04:08 rue_more doing the ansi control codes right out of the avr worked nice too
04:10 rue_more there would be no way to varry the threshold votlage with the tl431
04:11 rue_more this is quickly digressing to an anlog circuit
04:11 GargantuaSauce_ power electronics are weird
04:12 rue_more if it weren't a variable power supply that went below 5V, this would be easy
04:12 rue_more huh
04:12 rue_more sometimes looking at something different fixes it
04:13 rue_more what I'm building, is REALLY a class D amp....
04:13 rue_more ....
04:13 rue_more so what I need, is a class D amp circuit
04:13 rue_more a dc coupled one
04:24 rue_more PAM8403
04:26 rue_more I bet that half the output could drive a logic level mosfet
04:26 rue_more arg, they dont make proper P channel logic level ones tho
04:38 rue_more the class D would just convert the analog to pwm tho
04:38 rue_more so I'd just be exploiting it as a high freq pwm converter
04:39 rue_more but the lm393 should be able to operate fast enough
04:40 rue_more and has two channels, so I can use one for the ramp and the other as the comparitor
04:42 rue_more hmm, maybe use up my 'oops these rail to rail amps are only good for 5V'
05:05 rue_more http://2.bp.blogspot.com/-jylVVeGvqUU/UAXibEAaXXI/AAAAAAAAAHs/_C4t4ik2GDQ/s1600/Fig%2B3%2BCC%2BOperation%2BCircuit.bmp
05:05 rue_more so I'm on this overall topology then
05:06 rue_more but the current sense resistor is really an amplifier circuit with its own supply ont eh positive rail and the series pass transistor is really a pwm buck converter
05:07 GargantuaSauce_ have you considered using an actual smps controller
05:07 rue_more yea, they dont go down to 0V
05:07 rue_more naturally
05:08 rue_more if I get really fancy I can make them think that 0V is really 5 or 2.5 or whatever their min. is
05:08 GargantuaSauce_ i guess you could put an amplifier on its sense/feedback pin yeah
05:08 rue_more usually done by dropping the - rail of the control circuit by the offset
05:10 rue_more a plain old adder wouldn't work, cause it would trim the 2.5->5V range off the top of the available range
05:11 rue_more I'd rather not have the main supply dialed to its full 36V
05:11 rue_more my output goal is 30V
05:15 rue_more hmm, common emitter amp with a offset of 2.5V
05:18 rue_more varrying it is still a problem tho
05:18 rue_more my dac outputs 2.5V +- 1.25V
05:20 GargantuaSauce_ are you not using the msb or something
05:22 rue_more that its output range
05:22 GargantuaSauce_ weird
05:22 rue_more I got some rail-rail to stretch it out
05:22 rue_more its a 16 bit audio dac
05:23 rue_more ** that outputs DC just fine
05:23 GargantuaSauce_ ah ok so it's made to be capacitively coupled
05:23 rue_more I tested it
05:24 rue_more andits stereo, so I can use one chip for the voltage and current setpoints
05:26 GargantuaSauce_ cool
05:29 rue_more http://dangerousprototypes.com/forum/download/file.php?id=8959&mode=view
05:29 rue_more hmm
05:30 rue_more dont know why its got two buffers in the middle
05:30 rue_more make its shaping
05:30 rue_more maybe
05:30 rue_more I'm sure the input is being driven to distortion
05:32 GargantuaSauce_ lol
05:33 rue_more http://www.google.ca/imgres?imgurl=http%3A%2F%2Fgeekcircuits.com%2Fwp-content%2Fuploads%2F2010%2F02%2Fpower-class-d-amp.png&imgrefurl=http%3A%2F%2Fwww.groupsrv.com%2Fscience%2Fabout585204.html&h=476&w=1022&tbnid=qF87Pd68Ut4eAM%3A&zoom=1&docid=GqXAH-e6y573nM&ei=Xu7-U-DmMK3BiwKp7ICYBg&tbm=isch&ved=0CD4QMygXMBc&iact=rc&uact=3&dur=1194&page=2&start=20&ndsp=20
05:33 rue_more I'm pretty sure
05:33 rue_more http://geekcircuits.com/wp-content/uploads/2010/02/power-class-d-amp.png
05:33 rue_more (sorry)
05:34 rue_more I'm pretty sure that the 'out' output is of the wrong polarity for a monostable
05:35 rue_more ok I'm crashing
05:36 GargantuaSauce_ wellll you dont exactly want a class d amp of course because they all operate open-loop
05:36 rue_more yea
05:36 rue_more they tend to lack current control aswell
05:36 rue_more but it would work for an analog->pwm stage
05:36 GargantuaSauce_ yeah
05:37 rue_more http://2.bp.blogspot.com/-jylVVeGvqUU/UAXibEAaXXI/AAAAAAAAAHs/_C4t4ik2GDQ/s1600/Fig%2B3%2BCC%2BOperation%2BCircuit.bmp
05:37 GargantuaSauce_ well no
05:37 rue_more ^^ replace series pass
05:37 GargantuaSauce_ i dont like the low side inductors
05:37 rue_more no, I'd remove them, have it control a standard buck circuit
05:37 GargantuaSauce_ yeah ok
05:37 rue_more it'd just generate the pwm
05:37 rue_more it would drive the fet nicely ;)
05:38 rue_more technically, the complimentrary outputs probably open themselfs up to syncronous rectification
05:39 rue_more which I suppose means one has to be carefull the inductor never goes discontinious
05:39 rue_more pff, this is a minefield of lame looking options
05:41 rue_more the chinese regualtors had two faults, they only went down to like 1.2V, which I was gonna live with, and the feedback didn't allow for microcomputer control which I was gonna live with and just have microcontroller monitoring
05:41 rue_more but then they had low side current sense...
05:42 rue_more I designed a good high side current sense, you should see tho what it has to do to convey the current to the common when its standing on a rail that goes from 0 to 36V
05:43 GargantuaSauce_ theres a reason hall effect sensors are on the market :V
05:43 rue_more too much noise
05:43 rue_more and dc offsets galore
05:44 rue_more the chinese ones have more noise than signal
05:44 rue_more http://www.aliexpress.com/item/30A-Current-Sensor-Module-ACS712-Module/1861948305.html
05:44 rue_more ^^ those things
05:44 GargantuaSauce_ oh yeah no i did nooot mean those
05:45 rue_more I bought a bunch beofre I tested one out...
05:45 GargantuaSauce_ though i do have a few of those guys. should mess with them
05:45 rue_more the noise was seriously 5x the signal
05:45 GargantuaSauce_ probably ok for motor control
05:45 GargantuaSauce_ or just monitoring
05:45 rue_more if you look at the datasheet you will see, hinted, that tou should not be less than about 2 sec
05:47 rue_more bought a bunch for like $1 ea
05:48 rue_more they play with the listings too
05:48 rue_more lots of the 5A ones have 30A chips on them
05:48 rue_more so you get even less signal for your noise
05:50 mumptai is that going to be an audio-amp or a powersupply?
05:50 rue_bed wow 3:30am
05:50 rue_bed a bench power supply
05:51 mumptai ahh ;)
05:51 rue_bed but the audio amp is doing a better job of the pwm so far
05:51 rue_bed I might dial it down to 40khz, I wanted to try going high (250k) but whatever
05:52 rue_bed most of my chips wont slew fast enough to do 250khz
05:52 mumptai decent mosfet drivers are indeed tricky
05:52 rue_bed drivers are ok
05:52 mumptai sync output?
05:53 mumptai ehh, sync rectification
05:53 rue_bed I have a transistor driver thats down to a few ns, but if you hook an LM386 up in x10 mode it does a DAMN good job as a fet driver
05:54 rue_bed iirc about 1ns
05:55 rue_bed (and, compared to fet drivers, the LM386 is freaking cheap)
05:55 mumptai interesting
05:57 rue_bed hah oh drat, tommorow is garbage day, I have to get up in the morning and put it out
05:57 rue_bed I'll sleepwalk
05:58 rue_bed I have 2.5 hours to rest till then
05:58 mumptai not much night left
05:59 GargantuaSauce_ cant you just do it now?
06:00 GargantuaSauce_ or are bylaws there dumb
06:00 rue_bed I'm crashing
06:00 rue_bed and the bear will get it
06:00 rue_bed and crows
06:00 rue_bed the bears tip it over so the crows can spread it around
06:01 GargantuaSauce_ i see
06:01 rue_bed the bears also tear down the trees so the deer can eat them
06:02 mumptai indeed pretty nice bears
09:47 rue_bed ok, I got the 4 garbage points and its out on the road
09:48 rue_bed that component tester is pretty cool
09:49 rue_bed I dreamt I was an N channel jfet trying to get my bipolar journeyman ticket
10:01 mrdata nice
10:02 mrdata i think i'll buy some jfets
10:02 mrdata just to play with them
10:36 rue_bed at about 12 the truck needs to go to the shop
10:36 rue_bed I need breakfast
10:37 rue_bed I need to check the ita exam date range
10:37 rue_bed I suppose I should do some aluminum casting
10:38 rue_bed I wonder if $25 is too much for a tiger torch
10:38 rue_bed I'm sure they are usually pretty cheap
10:39 rue_bed I need to make a lid for the smelter, and fix up the inner lining
10:46 rue_bed make the new cope and drag
10:48 rue_bed and make a disc sander
10:54 rue_bed huh, looks like everyone is using wood for making cope/drag
10:54 robotustra what is this?
11:14 rue_more cope/drag are the halves of the containment box for casting
11:15 rue_more maybe I can use a 3842 as a pwm genorator
11:16 rue_more no
11:16 rue_more wrong mode
11:18 rue_more need to build a new foot rest for the computer
11:53 rue_more http://forum.allaboutcircuits.com/picture.php?albumid=45&pictureid=665
11:53 rue_more with .001uF and 2.7k
12:17 robotustra rue_more: what are you doing?
12:19 rue_more switching power supply
12:20 rue_more I like the 555 citcuit because of the component count
12:20 rue_more funny thing, the formula there is out by 200% :)
12:21 rue_more http://www.microchip.com/forums/download.axd?file=0;727546
12:21 rue_more usually I'd do the sea of resistors like that
12:21 rue_more which granted, can be controlled a bit more, but whatever
12:23 robotustra if you'll spend your time on what ppl already did 1000 times - you'll waste your life
12:23 robotustra buy PC power supply
12:23 robotustra or use TL494
12:24 rue_more a) the computer power supply isn't variable from 0 to 30V
12:24 robotustra buy chinese PS
12:24 robotustra it's exactly what you need
12:24 rue_more b) the tl494 can be used as a pwm genorator, but it cant do 100% duty and its ref is 5V
12:25 robotustra ok
12:25 robotustra s you do specific PS?
12:25 rue_more maybe you dont understand, this supply I'm building will show volts and amps, can be controlled by usb, and over which displays volts, amps, and watts
12:25 robotustra but what for
12:25 rue_more its a bench supply
12:25 rue_more usb controllable bench supplies (2 channel) are $$$$$$$$$$$$$$$$
12:26 rue_more I can build one much much cheaper
12:26 robotustra we have PS which we read and control through I2C
12:26 rue_more 30V 5A?
12:26 robotustra for sure
12:26 rue_more 0-30V?
12:26 rue_more with current sense on the positive rail, not off ground?
12:26 robotustra 29V 300A
12:27 robotustra any voltage
12:27 robotustra settable
12:27 rue_more erm, motor driver?
12:27 rue_more can you set the voltage AND current limit?
12:27 rue_more to within .01V and 10ma?
12:28 rue_more must be less than 10ma
12:28 rue_more must be 2ma
12:28 rue_more cause 20 steps is 1A
12:28 rue_more no
12:28 rue_more 5ma
12:28 rue_more :
12:28 rue_more :)
12:30 rue_more its not great stepping for driving leds direct, but its sure better than my existing supply
12:33 rue_more http://www.ebay.ca/itm/BK-Precision-9173-Dual-Channel-Range-DC-Power-Supply-w-USB-interface-220V-/321498264546
12:34 rue_more I'm prettymuch building that, but with analog meters (for easily seeing trending), real knobs, but for about $60
12:34 rue_more oh and mine runs on 120V, not 220 like all the ones online...
12:37 rue_more thats what I'm up to anyhow
12:43 rue_more its too bad the 555 dosn't put out a more triangular wave...
12:51 robotustra hm
12:51 robotustra ok, do it than
12:52 rue_more I am
12:52 rue_more so far its looking good
12:52 robotustra I have different kind of problem
12:52 rue_more whats your problem?
12:52 rue_more I'v had my head more than deep enough up my problem :)
12:53 robotustra I need something like ethernet<->multiple serial connection
12:53 rue_more easy
12:53 robotustra rs232?
12:53 rue_more ethernet<-> usb<->hub<->array of usb serial adapters
12:53 rue_more you know of usb over ethernet right?
12:53 robotustra does not work form me
12:54 robotustra I have no space to fit it in my robot
12:54 rue_more ah
12:54 rue_more how many serial ports?
12:54 robotustra it should be a pcb of size not more than 50x50 mm
12:54 robotustra I think I'll be happy with 4
12:55 rue_more :) use the new console system by valve
12:55 rue_more full gaming console in like 5x5cm
12:55 robotustra what is the new console system?
12:55 robotustra link
12:56 rue_more http://86bb71d19d3bcb79effc-d9e6924a0395cb1b5b9f03b7640d26eb.r91.cf1.rackcdn.com/wp-content/uploads/2013/01/valve-video-game-console-piston-steam-box.jpg
12:56 rue_more oh its bigger than I remember
12:56 rue_more oh well
12:56 rue_more http://assets.vr-zone.net/18618/xi3-piston.png
12:56 robotustra and another problem is a bunch of drivers for 4-20 mini DC motors
12:57 rue_more servo or raw
12:57 robotustra raw
12:57 rue_more how mini, >1A <1A?
12:57 rue_more what voltage?
12:57 robotustra 3-5V
12:57 robotustra law wattage
12:57 rue_more perfect
12:57 rue_more use fet gate drivers
12:58 rue_more dual low side fet driver = H bridge
12:58 robotustra tc4244
12:58 rue_more sop8
12:58 robotustra yes
12:58 rue_more sspo8 even
12:58 robotustra I use them in my eyes
12:59 rue_more k, so whats the problem?
12:59 robotustra it's not a problem but I heed a rs232 receiver to decode the command
12:59 rue_more decode?
12:59 robotustra yes, to spool high level command to send voltage to motors
13:00 rue_more ok, so
13:00 robotustra and read current feedback from each motor
13:00 rue_more you need to get from the serial to the wifi?
13:00 robotustra and send it back to rs232
13:00 robotustra no wifi
13:01 robotustra wires only
13:01 rue_more er, you gonna close loop it over ethernet?
13:01 robotustra my robot will not have any wifi
13:01 robotustra yes
13:01 rue_more latency?
13:01 robotustra ethernet - uart - drivers
13:01 robotustra 25 Hz
13:01 rue_more rrrrly....
13:02 rue_more oh god the 4244 is a beast
13:02 robotustra up to 200 motors
13:03 robotustra very good chip
13:03 rue_more how about...
13:04 robotustra where is MrCurious?
13:04 robotustra is he on vacations?
13:04 rue_more http://www.digikey.ca/product-detail/en/IX4428NTR/IX4428NTR-ND/4007119
13:05 rue_more 53c ea in volumes of 1
13:05 rue_more or there abouts
13:08 rue_more and if your crafty, you can pull some samples off old motherboards
13:09 rue_more there are better ones, 8R Ron isn't impressive, some of them are really really good
13:10 robotustra sorry, I use this one http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en010667
13:10 rue_more ah!
13:10 robotustra 4424
13:11 rue_more better
13:11 rue_more I must have picked up a different 4424
13:12 rue_more huh, 8R again...
13:12 robotustra it's quite powerful for my robot head and neck
13:12 rue_more cool
13:12 robotustra what is it?
13:12 robotustra 8 ohms?
13:12 rue_more yea
13:12 rue_more the Rdson
13:12 rue_more (max)
13:12 robotustra what is is?
13:13 robotustra it
13:13 rue_more yoru fet driver chip
13:13 robotustra you mean that it will heat?
13:14 rue_more well
13:14 rue_more zippo:/home/dan/.xchat2/downloads# ohm -i 1 -r 8
13:14 rue_more Wattage is: 8.000000
13:14 rue_more Current is: 1.000000
13:14 rue_more Voltage is: 8.000000
13:14 rue_more Resistance is : 8.000000
13:15 rue_more depends on your load current
13:15 robotustra 100-200 mA
13:15 robotustra up to 500 mA
13:15 robotustra not more
13:15 rue_more zippo:/home/dan/.xchat2/downloads# ohm -i 0.5 -r 8
13:15 rue_more Wattage is: 2.000000
13:15 rue_more Current is: 0.500000
13:15 rue_more Voltage is: 4.000000
13:15 rue_more Resistance is : 8.000000
13:15 robotustra and pulsed
13:15 robotustra it's nothing
13:15 rue_more its a bit of soemthing
13:16 rue_more its 100A to 200 motors :)
13:21 rue_more thats like 5 PC power supplies
13:22 rue_more you should see the numbers on how much power I need to operate the 188 valves for my pneumatic mecha
13:27 robotustra that's why I don't use pneumatic or hidraulic valves
13:27 robotustra 188 valves?
13:27 robotustra 188 DOF?
13:27 robotustra what is the total power of your meha?
13:31 robotustra I plan to use less than 120 DOF for mine
13:34 rue_more iirc 2hp will do
13:35 rue_more dosn't sound like much for a 12' mecha, but I tripplechecked it
13:35 rue_more 47 axis
13:35 rue_more hands are 3 digit
13:36 Tom_itx no workie to day?
13:36 robotustra 12' - are you inside?
13:37 robotustra 2 hp is not enouph, BD Atlas consume 11kW
13:41 robotustra Tom_itx: you mean rue_more does not work for food today?
13:41 robotustra :)
13:43 Tom_itx i'm betting he forgot about food today
13:54 robotustra do you feed him?
15:13 rcaskey hey all, anyone here have any practical experience with Roomba/Scooba?
15:15 deshipu just limited to watching videos of cats riding them
15:15 rcaskey I actually just want to clean my floor with them :(
15:16 deshipu ridiculous
15:16 deshipu get a cat
15:16 rcaskey i've got a dog
15:16 rcaskey he will probably bark at it so i'd lock him out when it was on :P
15:16 deshipu get a cat, it will terrorize the dog
15:16 deshipu and then ride the roomba
15:17 rcaskey I don't want my dog terrorized, i would make me sad
15:17 deshipu the cat doesn't mind
15:21 rcaskey also I give my dog 50/50 on just killing the cat
15:33 Skwint I have encountered a roomba in real life
15:33 Skwint it was experimenting with various approaches to avoiding a really evil obstruction known as a chair leg
15:34 rcaskey Skwint, did it succeed?
15:34 Skwint yes
15:34 Skwint but perhaps not as efficiently as a human :p
15:34 rcaskey from what I'm reading if you have an average size house a Roomba isn't gonna cover the whole thing
15:35 Skwint I think they do a good enough job, but unless you find amusement in the thing itself you are better off just vacuuming your house once a week by hand
15:35 rcaskey Yeah or for $800 for the top end one, better of paying someone to vacuume it 100 times
15:35 Skwint plus that generates employment
15:35 rcaskey (if they have other things to do anyway vacuuming doesn't take all that long if your not lazy, like I am)
15:35 deshipu employment is overrated
15:35 deshipu more robots!
15:35 Skwint I need to marry a clever girl
15:36 Skwint so she can go to work and I can vacuum for her
15:36 deshipu marry a clever guy
15:36 Skwint I'm not really into guys
15:36 deshipu love is blind
15:36 Skwint it has an impressive sense of touch though
15:37 deshipu that's ok, he will be at work all the time anyways
15:37 rcaskey but i've got 3000 sqft down stairs to vacuume and I'm thinking it's not gonna get the job done
15:37 Skwint it's a bad solution all round
15:37 Skwint we should design self cleaning floors
15:37 deshipu or ones that don't get dirty in the first place
15:38 deshipu put them in plastic wraps
15:38 rcaskey Skwint, I can activate my dog door on a schedule, that's pretty close to automated mopping
15:38 Skwint you could spray the entire floor in that never-wet stuff
15:38 rcaskey then you coudln't clean it :P
15:38 Skwint but you'd have an excellent excuse!
15:39 deshipu or fill your house with water
15:42 rcaskey aka the ToolTime method
15:58 fluffywolf I'm also having a hard time finding a girl... why is mature, intelligent, honest, sane, and good with a strapon so hard to find?
16:01 uffywolf isn't into guys ei
16:31 rue_more robotust1a, being inside a 12' mecha would be insanely unsafe
16:31 rue_more I have a few days off
16:32 rue_more I have 2 roomba's on the shelf with varrious ailments
16:34 Tom_itx what's 750c in F?
16:37 fluffywolf You have: tempC(750)
16:37 fluffywolf You want: tempF
16:37 fluffywolf 1382
16:37 fluffywolf you can also *1.8+32, or ask google. :P
16:38 rue_more https://www.google.ca/search?site=&source=hp&q=750c+in+f&oq=750c+in+f&gs_l=hp.3..0i22i30l2.16080.18795.0.19049.10.10.0.0.0.0.222.744.9j0j1.10.0....0...1c.1.52.hp..2.8.468.0.mZF0o9-868A
16:38 rue_more 1382
16:38 Tom_itx what about 800c?
16:39 rue_more http://bit.ly/1ortD6c
16:40 fluffywolf !math
16:40 Gigs fluffywolf: Usage: !math <mathstuff> e.g. 1+1
16:40 fluffywolf !math 850*1.8+32
16:40 Gigs fluffywolf: 850*1.8+32 = 1562.0
16:40 fluffywolf !units
16:40 Gigs fluffywolf: Usage: !units fromunit tounit e.g. 1km mile
16:40 fluffywolf !units tempC(800) tempF
16:40 Gigs fluffywolf: tempC(800) = tempF(1472)
17:28 robotust1a rue_more: to be inside macha is what russians and japanise would do, but of cause you are canadian
17:52 rue_shop3 yea I'm not that blooming crazy
17:53 rue_shop3 if I'm driving a P channel fet off the top rail, I think I use a low side driver....
17:53 rue_shop3 my generic fet drivers are failing me
17:53 rue_shop3 even 64khz isn't switching pretty
18:04 robotust1a < rue_shop3> yea I'm not that blooming crazy
18:04 robotust1a yes you are, if you want 188 valves
18:11 fluffywolf valves of the mechanical or thermionic variety?
20:02 rue_more easy to tune them
21:27 rue_shop3 I cast a more generic cylinder of aluminum today
21:27 rue_shop3 maybe i can machine it down into something
21:27 orlock make me a new shower tap!
21:27 rue_shop3 it came out pretty good, but I think there is still a shrinkage problem
21:28 orlock rue_shop3: ever dealt with shower type plumbing?
21:28 e_shop3 hands orlock a hot, disfigured lump of aluminum "all ready to be machin
21:28 orlock theres play in the shaft, when the knob is turned so water comes on, it can wobble from side to side, and it makes a horrid noise
21:32 rue_more sorta a "kack-kack-kack-kack-ka-kack-kack" noise?
22:11 theBear i won't eat your garbage, i promise
22:12 theBear yeah, like rue was gonna say, it probly ain't the tap, i forget the term, but it's the pipes.. combination of expansion/balooniness and general wobble due to insufficient fixings inside the walls
22:14 orlock nah
22:14 orlock its not water hammer
22:14 orlock i can feel the play as the tap unscrews
22:15 orlock and you can wobble the tab hadle left/right/up/down and feel the play
22:15 orlock it even changes the water flow
22:15 orlock i can get a new "spindle" for under $10 that i think goes between the pipe and the knob
22:16 orlock like the threads worn or slightly cross threaded and theres a lot of play
22:19 rue_more hmm
22:20 rue_more anyone know a company that does the trolley robots that run around factories?
22:20 rue_more I think I want some replacement batteries
22:21 GargantuaSauce_ kuka has a line of those
22:24 rue_more cant find them anywhere on their page
22:30 rue_more aha, called an AGV
22:38 rue_more http://www.transbotics.com/products/automated-guided-cart/
22:39 fluffywolf orlock: you can generally get an entire replacement moving bit assembley at the hardware store. pop off the handle, unscrew the big nut, and take the entire thing that comes out to the hardware store, to match up with their selection.
22:39 fluffywolf often under the description "cartridge".
22:46 fluffywolf rue_more: what was that about 188 valves earlier?
22:46 rue_more my 12' mecha
22:46 fluffywolf pneumatic?
22:47 rue_more everytime I see a washing machine I rape it for its valves
22:47 rue_more yup
22:47 fluffywolf you can get valve manifolds surprisingly cheaply on ebay.
22:47 rue_more it has to be sub $1/valve
22:47 fluffywolf yes
22:47 fluffywolf I picked up an 8 valve manifold for $5 not too long ago.
22:48 fluffywolf nice big ones, 24V coils, two coils per valve.
22:48 rue_more loest I'v seen is $5/valve
22:48 rue_more was the BID $5?
22:48 rue_more or the buy it now
22:48 rue_more cant be spool valves, they are too slow
22:49 rue_more washine machines use a diaphram valve that is really fast
22:49 fluffywolf the bid. I won it at that price.
22:49 rue_more ah
22:49 rue_more anything shipping form the usa is typically $45 shipping to canada
22:50 fluffywolf I don't see any really cheap ones right now, but ebay's search has gotten so fucking useless it's hard to know.
22:51 fluffywolf whatever fucking idiot decided you should only see three items per screen needs to be shot.
22:51 rue_more :)
22:51 rue_more hmm, its 8:30pm
22:51 rue_more so...
22:52 rue_more what should I work on over the next 7 hours?
22:52 rue_more I shoudl start with tea, or it wont be 7 hours
22:52 fluffywolf I suspect buying a proper valve manifold works out cheaper than the fittings to connect washing machine valves.
22:54 fluffywolf http://www.ebay.com/itm/SMC-NZ4125-0152F-AIR-PNEUMATIC-SOLENOID-VALVE-MANIFOLD-24VDC-EI-30-80-/380875751825 when you get manifolds like that, all you do is feed it an air source, and you have tubing fittings already on it to run straight to your cylinders... no extra fittings needed, and only one supply line fitting per 8-20 valves...
22:56 fluffywolf http://www.ebay.com/itm/SMC-VV5Q21-07C4FS0-S-MANIFOLD-WITH-7-VQ2301NR-5C-VALVES-/321501373017
22:56 fluffywolf that one's not even used, $15 with no bids
22:57 fluffywolf pneumatics are amazingly cheap on ebay
22:58 fluffywolf http://www.ebay.com/itm/Lot-of-5-Solenoid-Vacuum-Valves-Manifold-Koganei-Ltd-SMC-Taiyo-Ejector-Unit-V310-/281424023764
23:03 fluffywolf 24 valve manifolds are easy to get... how much are you going to spend on fittings connecting 188 valves vs 8 manifolds (with all fittings already attached when you buy them)...
23:05 fluffywolf I have some SMC ones that stack end-to-end, so the only limit to how many valves you can put in a block is the air supply from one end to the other.
23:10 rue_more that first one you listed, is $50 with $40 shipping
23:10 rue_more and there will be customs processing charges on top
23:10 fluffywolf it was just an example. the best deals are waiting for an auction. they rarely get many bids.
23:11 rue_more the seond one is $34 shipping
23:11 rue_more + import charges
23:11 fluffywolf so go search ebay.ca. my account is on ebay.com. :P
23:11 rue_more the last one says they dont know where canada is, so they cant ship there
23:12 rue_more I can get nice free washing machine valves all over
23:12 rue_more all the same...
23:14 fluffywolf and only 564 fittings to plumb them!
23:14 fluffywolf resulting in a huge mess, instead of something neat.
23:14 fluffywolf also, washing machine valves are unreliable, and tend to stick closed at high pressure.
23:16 fluffywolf and buzz, and need 120V.
23:17 uffywolf has some experience with pneumatics, and would never suggest that solution.
23:17 fluffywolf hrmm, according to ebay.ca, things in canada are stupidly overpriced and hard to find.
23:17 fluffywolf may I suggest moving?
23:18 MrC123 canadians are fiercely loyal
23:19 MrC123 they love paying vat for the privilege of having packages delayed and played with before arriving....
23:23 fluffywolf why are you using pneumatics for a mecha anyway? hydraulics are much better for crushing your enemies. :P
23:23 rue_more no
23:24 rue_more hydraulics are slow and really really expensive to do servo control with
23:24 fluffywolf how much are you going to spend on fittings to plumb 188 valves?
23:25 rue_more if it could be done with hydraulics, one of the people who already tried it surely would have succeeded by now
23:25 rue_more the plastic garden hose fittings are really cheap, but they can also be found free
23:25 rue_more usually washing machines have the hoses still attached,
23:25 rue_more tahts 4 ends ea
23:26 fluffywolf I think that with fittings (supply and lines to cylinders), and valuing your time at anything, washing machine valves will cost more, take much longer, add much more weight and room, and result in an unreliable product.
23:26 rue_more well you start working on a hydraulic mecha and I'll continuie with my pneumatic one
23:26 rue_more oh, budget for the whole mecha is $120
23:27 rue_more you can go up to 200% of the budget
23:27 fluffywolf yeah, good luck with that.
23:27 rue_more any money the project makes before it finishes does not count as part of the budget
23:27 fluffywolf I've put some design effort into hydraulics that would be suitable for a mecha, but my application was not a mecha. heh.
23:28 rue_more I'v got myself stuck on how to control the counteractuators
23:28 fluffywolf I've been designing some ultra-efficient hydraulic motors, trying to get efficiency well above 95%...
23:28 rue_more the alg to dump one side vs load the other
23:29 rue_more fluffywolf, yea, proportionate valves will kill any project budget for soemthing like that
23:29 fluffywolf you know a dual-acting cylinder (air on both sides of the piston) acts just like your "counteractuators" with a single component, right?
23:29 fluffywolf it doesn't have any valves.
23:29 rue_more fluffywolf, you know how much air muscles cost to make, right?
23:29 fluffywolf well, other than the poppet valves on each cylinder.
23:29 rue_more so how do you control your hydrailucs without valves, individual pumps?
23:29 fluffywolf one that doesn't suck? more than buying a used ebay air cylinder. :P
23:29 MrC123 http://hackaday.com/2014/08/26/new-chip-alert-the-esp8266-wifi-module-its-5/
23:30 rue_more seen it
23:30 fluffywolf rue_more: realtime control of the motor displacement, including which direction positive is. :)
23:30 rue_more I'v already confirmed that the digital valves will work with the air muscles
23:31 fluffywolf if you set the motor displacement to zero, fluid doesn't flow...
23:31 rue_more did you see the video?
23:31 rue_more https://www.youtube.com/watch?v=z2xWgEdiTwc&index=5&list=PLEAC147CDF6E03FEA
23:31 rue_more its spring counter, so I'm half way there
23:32 fluffywolf my design has no radically new ideas, just highly optimized for efficiency, and the unusual application of running full pressure into a stalled motor 99% of the time.
23:32 fluffywolf youtube and my internet connection (cell modem) don't play well together, but I'll try...
23:33 fluffywolf normal hydraulic motors have very high stiction and leakage when stalled, and eventual failure, due to the valves being two metal plates sliding over each other. when stalled, the fluid layer that keeps them from rubbing is squished out.
23:35 fluffywolf when spinning, this works great, as a fluid layer forms keeping them apart... the efficiency isn't great, nor is the leakage, but they work well and last a long time... but for an application where the normal state of the motor is stalled, that won't work.
23:35 rue_more you making the pumps?
23:36 fluffywolf brb
23:36 fluffywolf video ~10% loaded.
23:36 rue_more :)
23:36 rue_more just that one, its gonna try to play the rest of the series
23:37 rue_more hahah youtube broke
23:39 fluffywolf yes
23:39 fluffywolf well, I would be... it's on the list-of-projects-for-when-I-have-spare-time-and-money.
23:40 rue_more int eh first of that series (that one was the last) the video is suppoed to end when the video ends
23:40 rue_more it plays out the rest of the musci
23:41 fluffywolf that's not a new video. I've seen it before.
23:42 rue_more k, well, thats using washing machine valves
23:42 fluffywolf I'm not viewing any more videos. the first one is only partially loaded, and it costs me $11/GB.
23:42 rue_more the great thing is
23:42 rue_more that the larger the muscles, the easier it is to use those valves
23:44 fluffywolf what is the maximum tension of that muscle?
23:45 rue_more as applied or max total force?
23:46 fluffywolf how much can you pull with it?
23:46 rue_more its got about 300g on it, it can lift 37kg
23:46 rue_more at 12psi
23:46 fluffywolf that's not much for its size.
23:47 rue_more that was the other reason, power desnity
23:47 fluffywolf you'd need a huge one for, say, a knee joint.
23:47 rue_more yea
23:47 rue_more they gang up really easy
23:48 fluffywolf the first application for my motors will be a hydrostatic transmission... they could be used for a mecha, but that seems like something that takes a lot of time and money for not much usefulness...
23:49 rue_more I have two verry important uses for my mecha
23:49 rue_more a) holding up the house number at the end of the driveway
23:49 rue_more b) cleaning the gutters
23:49 orlock goddamn gutters
23:50 orlock ours has a lawn in it :-(
23:50 fluffywolf lol
23:50 rue_more the nerve!
23:50 fluffywolf does it have a mind in it?
23:50 rue_more no, its purely remote
23:50 fluffywolf not your mecha, orlock's gutter. :P
23:51 orlock oh
23:51 orlock hah
23:51 uffywolf thought of that "dildo end effector" link looking at rue's air muscle
23:51 rue_more oh yea, the OTHER reason for pneumatics is because they are compliant
23:51 rue_more you cant have a 12' mecha without it having compliant joints
23:51 rue_more er its just gonna break
23:52 fluffywolf my motors are compliant... and not just compliant, regenerative. if you apply more force than it's commanded to put out, it pumps fluid back into the system.
23:52 rue_more so if they ahve a force impact, they absorb it instead of breaking?
23:53 fluffywolf AND capture the energy. :P
23:53 MrC123 NATO ..... Needs Another Time Out....
23:54 fluffywolf the downside is they need a very fast servo control mechanism for the cylinder displacement... I'm going for a built-in solenoid working a spool pilot valve which works the main valve and actuator...
23:54 fluffywolf since you can very the displacement in miliseconds, you can do all sorts of fun things.
23:55 fluffywolf (for those not familiar with hydraulics, the displacement of a pumo or motor is how much fluid is moved per one revolution of the shaft)
23:55 fluffywolf pump
23:56 rue_more https://www.youtube.com/watch?v=dJl2gFUgkEc
23:56 rue_more who can guess the first thing that will be used for?
23:59 fluffywolf dunno. is it worth waiting 10 minutes at $11/GB to look at it to see?
23:59 rue_more no