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[00:27:18] <rue_house> geez, all 3 printers running
[00:42:48] <jrowe47> https://www.tinkercad.com/things/aWZcPCUWMHS-expansive-motion-actuator/
[00:44:09] <jrowe47> if each of the coils could be operated independently, and could bend the whole mechanism 45 degrees down, what would be the degrees of freedom for this?
[00:44:35] <jrowe47> trying to think of a way to combine nylon artificial muscles with 3d printing for a robot :D
[00:45:14] <jrowe47> the column in the center is a flexible coupling, can bend in any direction
[00:45:22] <rue_house> page dosn't exist
[00:45:42] <z64555> "ooops"
[00:46:27] * jrowe47 fails
[00:46:48] <z64555> Presumably this is a tentacle/arm arrangment?
[00:47:06] <jrowe47> could be, or could fix one side to something rigid
[00:47:08] <z64555> a number of rings in the structure, with interconnecting muscles between each ring
[00:47:14] <jrowe47> https://www.tinkercad.com/things/aWZcPCUWMHS-expansive-motion-actuator/editv2?sharecode=rHfgAFIR6zzaDZWuiZJC0FkN-NVXj_s_6fCfzCqdRGk=
[00:48:41] <z64555> yeah, that's what it looks like
[00:48:54] <z64555> You'd have a DoF per opposing pairs of muscles
[00:49:19] <jrowe47> ok, so a simple 2dof actuator
[00:49:45] <jrowe47> cool, ty!
[00:50:10] <z64555> yw
[00:51:02] <jrowe47> was thinking that this could be encased in a gel solution of graphene to allow it to rapidly cool
[00:53:38] <jrowe47> one of the papers from a couple years ago used 6 .2mm coils to exert 1000 lbs of force
[00:54:21] <jrowe47> i think its only like 5% efficient or something to that effect, but it'd take all of $30 to make something like this
[00:54:44] <jrowe47> hell, 30 cents even
[00:55:05] <z64555> how much displacement, though
[00:55:33] <jrowe47> with a woven muscle, 10-40% i think
[00:56:01] <z64555> of what? the muscle's length?
[00:56:18] <jrowe47> multifilament arrangments can get pretty significant contraction
[00:56:30] <jrowe47> searching for a paper i saw earlier
[00:56:56] <jrowe47> but you could probably get it to bend 45 degrees really easily
[00:57:16] <z64555> 1000lbs of force is nice, but not widely useful if you can only move less than a millimeter
[00:57:37] <jrowe47> right
[00:58:28] <jrowe47> http://txchnologist.com/post/77720882890/fishing-line-muscles-could-make-superstrong-robots
[00:58:29] <z64555> but that may be significant if that was an angle, instead of a distance
[00:58:41] <jrowe47> 49% contraction
[00:59:03] <jrowe47> trying to control such a small displacement with any precision would be a pain in the butt
[00:59:40] <z64555> yeah, you'd be better off making an array of them and just bit-banging the ones you need to get the desired displacement
[00:59:47] <jrowe47> yup
[01:00:33] <jrowe47> but a single coil can get 49%, so just using a cluster of those to get crazy strength from it would make this workable
[01:00:57] <jrowe47> how would i improve the idea, do you think?
[01:04:41] <z64555> Why are you asking me, I don't know what you are thinking :P
[01:04:51] <jrowe47> lol
[01:05:23] <jrowe47> im thinking that this could be a cheap actuator to use in a robot
[01:06:18] <jrowe47> and i want to see if theres something mechanically that could be done to add DOF , range of motion, etc
[01:06:23] <z64555> the muscles themselves might be cheap individually, but getting a usable actuator out of them might not be so
[01:06:51] <rue_house> air muscles are the way to go for me so far, mostly because of the scale of my projects
[01:07:07] <jrowe47> i can 3d print one of these, I think
[01:07:10] <rue_house> I'd like to find a way of consistantly making the nylon muscles tho
[01:07:31] <z64555> adding DOF would be as simple as adding more muscle pairs
[01:08:09] <jrowe47> hmm, the 2 opposing pairs would allow circular motion, like a stick in a ball joint
[01:08:18] <z64555> yes
[01:09:01] <jrowe47> an addition pair on top and bottom ?
[01:09:13] <jrowe47> hmm
[01:09:31] <jrowe47> dunno where else you'd put an opposing pair of muscles to get more range of motion out of it
[01:09:31] <z64555> you can put another pair that's radial to one of the rings, and have it rotate the whole structure
[01:09:44] <jrowe47> oh
[01:09:57] <z64555> to get more range of motion, expand the diameter of the rings
[01:10:51] <z64555> and increase their height a bit, too
[01:11:22] <jrowe47> pair thats radial to the rings - so the coil would be coiled around the center column?
[01:11:38] <z64555> yes
[01:12:08] <jrowe47> a single helix wrapped around both sides
[01:12:11] <z64555> or around the outside of the, uh, pins
[01:13:16] <jrowe47> might be better with a rigid core to work off of instead of a flexy column
[01:13:27] <jrowe47> gonna ponder
[01:13:30] <jrowe47> lol, thank you :)
[01:32:35] <jrowe47> looks like you could probably rotate around 120 degrees
[01:38:15] <jrowe47> so a 3dof flexible plastic widget with a ton of torque, and encase it in flexible waterproof material like TPU, the torque would be around 170 kg/cm
[01:38:43] <jrowe47> that'd be something like 16 cubic centimeters
[01:41:23] <jrowe47> would need a strong metal spring core instead of plastic, and a conductive elastic to gauge position
[01:42:04] <rue_house> one of the neat things is that you dont need 4 actuators for 2 axies
[01:42:14] <rue_house> 2 axies can share 3 muscles
[01:42:31] <rue_house> thats a 1/4 reduction in actuation system
[01:42:44] <rue_house> for counteracting actuators
[01:42:48] <jrowe47> use 6 pins instead of 8?
[01:43:03] <jrowe47> not quite visualizing what you're thinking
[01:43:17] <rue_house> hey, I'm working on a 12' pneumatic mecha, I'v worked some things out
[01:43:26] <jrowe47> awesome
[01:43:33] <rue_house> you will love the answer better if you work it out
[01:43:37] <jrowe47> im thinking ultra-cheap hexapod
[01:43:54] <rue_house> pneumatic is only reasonable for large robots
[01:44:17] <rue_house> but I like that its compliant
[01:46:16] <jrowe47> you could rotate the mechanism 90 degrees and get the same range of motion?
[01:46:25] <jrowe47> hmm, no
[01:46:34] <jrowe47> any hints? heh
[01:47:30] <rue_house> na
[01:47:32] <rue_house> sleep on it
[01:47:46] <jrowe47> bah, I'm not due for bed for hours ><
[01:47:58] <z64555> rue_house: Trouble with that arrangement is that it tends to bind. My car mirror has that arrangement and I could never pivot the damn thing right
[01:48:13] <rue_house> !?!?!
[01:48:19] <rue_house> no way
[01:48:25] <z64555> yeah way
[01:48:40] <rue_house> its just reusted, evryone knows 12' mecha dont rust.
[01:48:42] <Anniepoo_> i wonder what fatigue life of these fishing line actuatos is
[01:48:52] <z64555> oh.
[01:49:01] <rue_house> anniepoo, my experience, 4 cycles :/
[01:49:09] <Anniepoo_> 8cp
[01:49:18] <jrowe47> millions of cycles
[01:49:26] <z64555> Megacycles. :D
[01:49:32] <jrowe47> lol
[01:50:50] <Anniepoo_> did somebody have a paper on this?
[01:51:55] <jrowe47> https://www.slashgear.com/mit-creates-bendable-artificial-muscle-fibers-from-nylon-28465521/
[01:52:25] <jrowe47> gotta drill down to the MIT source, many papers if you google nylon artificial muscle
[01:53:29] <jrowe47> sorry, wrong concept
[01:55:32] <rue_bed> I tried it, its realy hard to get the first buckle to go right
[01:55:50] <rue_bed> there are two ways it can buckle over
[01:56:05] <rue_bed> AND you CANT just let go of them after their wound
[01:56:25] <rue_bed> they are heat based, they do work
[01:56:37] <jrowe47> im talking about coils -
http://txchnologist.com/post/77720882890/fishing-line-muscles-could-make-superstrong-robots
[01:56:41] <rue_bed> yea
[01:56:42] <maiden> i have also played around with them.
[01:57:01] <maiden> the tricky part is the cooling ;)
[01:57:06] <maiden> and control
[01:57:15] <rue_bed> yea
[01:57:21] <maiden> best effect i have seen have been water based
[01:57:35] <maiden> quckly switching between hot and coold water
[01:57:46] <jrowe47> i think the trick is to use something that can transfer heat really quick
[01:58:25] <jrowe47> and graphene is really easy to make
[01:59:15] <rue_bed> too bad nobody makes thermopile thread
[01:59:36] <rue_bed> when you switch the polarity, the heat transfer switches directions
[01:59:41] <Anniepoo_> http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=1854080
[01:59:41] <jrowe47> hmm
[01:59:49] <Anniepoo_> theres the paper, stupid paywall
[02:00:07] <rue_bed> gnight
[02:00:09] <rue_bed> I'm in bed
[02:02:36] <z64555> jrowe47: which would be silver
[02:02:46] <jrowe47> could coat silver plated nylon with bismuth
[02:02:52] <jrowe47> efficiency would really suck, lol
[02:03:27] <z64555> nah, you'd have to thread it
[02:03:42] <z64555> plating would crack under expansion/contraction of the nylon
[02:04:11] <maiden> https://www.researchgate.net/profile/Lianjun_Wu/publication/277137306_Nylon-muscle-actuated_robotic_finger/links/5809446508aeef21df0e992a.pdf?origin=publication_list
[02:05:32] <maiden> see here as well:
https://groups.google.com/forum/#!topic/inmoov/q2IyAx69Wzg
[02:06:28] <jrowe47> i was thinking the mechanism i posted would have coolant running through the core, with thermal paste encased around the muscles, and the thermal paste interfacing with the coolant against TCPG
[02:07:09] <maiden> http://iskanderus.ru/wordpress/ have a machine for making artificial muscles and have an inmoov hand actuated with nylon muscles, check his youtube account.
[02:07:56] <maiden> i have been thinking of a wire-heated, water cooled solution.
[02:08:02] <jrowe47> so it'd be maintained at a low temperature, and you just apply current to get motion
[02:08:19] <jrowe47> could use conductive elastic between the pins to measure position
[02:08:30] <Anniepoo_> ever make rope?
[02:08:41] <Anniepoo_> rope has locked in twist
[02:09:22] <SpeedEvil> Which often counters
[02:09:27] <Anniepoo_> each strand is under torsion, but the strands are then wound together the other direction,
[02:09:27] <SpeedEvil> sozero twist
[02:09:31] <maiden> btw, i think it have been concluded that thin cu wire is best for heating, for various reasons. cant remember where or what papers i base that on..
[02:09:32] <Anniepoo_> yup
[02:09:45] <SpeedEvil> zero net twist
[02:09:57] <SpeedEvil> I've been trying to work out light linear actuators.
[02:10:23] <SpeedEvil> ^cheap
[02:10:25] <SpeedEvil> fun
[02:10:35] <SpeedEvil> Muscle-like - pull only
[02:10:36] <jrowe47> https://www.tinkercad.com/things/aWZcPCUWMHS-expansive-motion-actuator/ - shouldnt be any twist issues
[02:11:11] <jrowe47> maiden, probably because it cools and heats more quickly than the nylon, and its cheap and easy
[02:11:14] <maiden> https://www.youtube.com/user/Iskanderuse/videos
[02:11:45] <jrowe47> thats not bad
[02:11:46] <maiden> jrowe47, yes and probably have better mechanical properties as well.
[02:12:08] <jrowe47> wait
[02:12:13] <jrowe47> https://www.youtube.com/watch?v=GLf0Z1I2pKg
[02:12:15] <jrowe47> thats horrible
[02:12:39] <jrowe47> lol, not technically, but the amount of design and effort that went into that is crazy
[02:15:07] <SpeedEvil> https://upload.wikimedia.org/wikipedia/commons/f/f0/Carpal-Tunnel.svg
[02:15:28] <SpeedEvil> The white ovals are all actuator tendons in the real hand
[02:15:43] <SpeedEvil> 21 of them.
[02:15:59] <SpeedEvil> There are also muscles in the hand, adding more axes.
[02:16:15] <jrowe47> crazy
[02:16:28] <SpeedEvil> 23,rather
[02:17:13] <jrowe47> all those linear actuators to create our hands range of motion
[02:17:44] <Anniepoo_> it's weird they used hot and cold water to drive this muscle
[02:17:57] <SpeedEvil> A few are redundant and could be simplified.
[02:18:27] <SpeedEvil> but most have some function if you want a hand flexible enough to play the piano and turn a tiny screwdriver
[02:20:08] <jrowe47> https://www.disneyresearch.com/publication/high-performance-robotic-muscles/
[02:21:09] <SpeedEvil> that is interesting
[02:23:13] <jrowe47> im gonna poke at the idea some more, then buy some materials next week
[02:24:21] <jrowe47> but it'd be awesome to be able to 3d print an actuator for pennies that had the torque of a $500 servo
[02:26:12] <Anniepoo_> how do you measure position with these sorts of actuators?
[02:26:19] <SpeedEvil> something external
[02:26:35] <Anniepoo_> I'm not seeing it on many of these setups
[02:26:39] <SpeedEvil> Anything from LASER interferometry to measuring joint angles
[02:26:56] <jrowe47> or conductive elastic between the pins
[02:26:57] <jrowe47> then measure resistance
[02:27:15] <jrowe47> 4 connections to measure position on 2 axes
[02:27:17] <Anniepoo_> hmm... you have a source for conductive elastic?
[02:28:00] <jrowe47> http://www.blackmagic3d.com/Conductive-p/bm3d-tpu-175.htm
[02:28:22] <Anniepoo_> thanks!
[02:28:57] <jrowe47> would have to print it in a coil, i think, im not sure tpu is all that elastic
[02:30:09] <jrowe47> but yeah, aside from the thin copper wire and the nylon, the whole deal could be printed of some tough, flexible plastic
[02:32:25] <Anniepoo_> wonder how much this conductive TPU varies R as it's stretched
[02:32:34] <jrowe47> no clue
[02:32:45] <jrowe47> lol, that part's in question
[02:33:21] <jrowe47> i would think its a safe assumption that R will measurably change, though - it's not terribly conductive
[02:34:21] <Anniepoo_> probably the volume resistivity changes little, so it's poisson ratio and increase in l
[02:34:42] <Anniepoo_> this stuff looks interesting:
[02:34:43] <Anniepoo_> http://www.blackmagic3d.com/Magnetic-PLA-Filament-p/bm3d-175-mag.htm
[02:34:58] <jrowe47> i have some graphene PLA
[02:35:20] <jrowe47> havent gotten it to print yet, my nozzle might be too small
[02:36:38] <Anniepoo_> I talked manufacturer out of a sample of material called coolpoly
[02:36:59] <Anniepoo_> it's got about the same thermal conductivity as aluminum
[02:37:08] <jrowe47> neat
[02:37:38] <Anniepoo_> bur is an elastomer, shore 80 or so rubber
[02:37:40] <maiden> <SpeedEvil> but most have some function if you want a hand flexible enough to play the piano and turn a tiny screwdriver
[02:37:44] <maiden> lol..
[02:37:48] <maiden> sorry..
[02:38:01] <maiden> https://www.youtube.com/watch?v=GOvpSyYvGDk
[02:38:15] <maiden> copy paste fail on my part..
[02:38:42] <jrowe47> i wonder if the resistance of silver plated nylon changes measurably
[02:40:43] <jrowe47> anyhow, I cant figure out how to get rid of the 4th actuator without adding a linkage
[02:41:02] <jrowe47> and that defeats the goal of having a simple 3d printable actuator
[02:41:04] <Anniepoo_> twisted string actuators can have high strength
[02:42:24] <maiden> i am working on an Series Elastic Actuator
[02:42:25] <maiden> http://roboticravings.blogspot.se/
[02:42:37] <maiden> that is 3d printable and open source.
[02:43:53] <Anniepoo_> https://www.youtube.com/watch?v=iMMGfzYXwAU
[02:44:11] <maiden> would like to evaluate this with a BLDC
http://hackaday.com/2017/01/17/3d-printed-strain-wave-gear-needs-your-help/
[02:44:32] <maiden> this might also come handy:
http://hackaday.com/2017/01/18/use-a-brushless-motor-as-a-rotary-encoder/
[02:45:16] <jrowe47> im sort of aiming for no motors
[02:46:03] <jrowe47> artificial muscle only, hopefully everything but the muscle, sensor, and wiring gets printed
[02:48:57] <Anniepoo_> 8c( I was born 30 years too early
[02:49:12] <Anniepoo_> lol
[02:50:13] <maiden> jrowe47, have you seen roboy?
https://www.youtube.com/watch?v=UYmOBpvSfMQ
[02:50:13] <jrowe47> lol, how old are you
[02:51:03] <maiden> i kind of like those actuators, its open source as well
https://github.com/roboy
[02:52:08] <Anniepoo_> 58
[02:52:19] <jrowe47> you might make the singularity
[02:52:24] <jrowe47> dont give up hope yet ;P
[02:52:51] <maiden> https://humanoides.fr/wp-content/uploads/2012/12/Blog_Humanoides_Fr_roboy_robot_compagnie_tendon.jpg
[02:52:58] <maiden> thats the roboy actuator
[02:53:28] <maiden> simple and useful ;)
[02:53:51] <jrowe47> uber expensive motor driven tho
[02:54:06] <maiden> its not that hard to change motor :p
[02:54:35] <jrowe47> true, but the nylon muscle actuator im thinking of will cost pennies and have the same torque as a $500 servo motor
[02:54:47] <Anniepoo_> so that linear pot or whatever is only measuring the spring's displacement for the SEA?
[02:55:05] <Anniepoo_> ah, missed 'encoder' on back of motor
[02:55:31] <maiden> and this would work fine with this motor:
http://www.ebay.com/itm/Micro-brushless-DC-5V-12V-52rpm-Planetary-Gearmotors-Hall-Sensor-Mini-Gear-Motor-/252533624820?hash=item3acc2d4ff4:g:-noAAOSw-itXwAPx
[02:55:48] <maiden> i have a bunch of them, but have not tested them yet.
[02:56:11] <Anniepoo_> jrowe, there are other things than torque - you want torque, buy a harbor freight bumper winch
[02:56:16] <jrowe47> if it works, i could build a hexapod that could run and jump like a facehugger
[02:57:43] <jrowe47> its all about if it works, though - just dreaming at this point
[02:57:50] <maiden> jrowe47, i agree, nylon muscles have potential, but nobody have figured out how to implement them in a control system and get good results/efficiency from them yet. might be a good research/PhD subject, but it will need a lot of research before it can be used.
[02:58:30] <jrowe47> or some innovation and experimentation - academia is overrated in this regard
[02:58:59] <maiden> "or some innovation and experimentation", as i said, a research project ;)
[02:59:10] <jrowe47> ahh, yeah
[02:59:19] * jrowe47 assumed , is an ass
[03:00:59] <maiden> jrowe47, have worked at a ABB Corporate Research for a little while, it was interesting, not exactly cutting edge.. my experience is that hobbyist R&D beat cooperate or academia R&D 9 days out of 10.
[03:01:31] <jrowe47> no doubt
[03:02:34] <Anniepoo_> hobbyists are just looking for something that works once. Academics are looking to understand why. Corporate needs it to work every time, so is somehwere between the two.
[03:02:49] <maiden> the best is probably pet/hobby project that works at a academia or a R&D company. or consultants sitting on the bench waiting for something to do.
[03:03:03] <Anniepoo_> though also corporations and/or academia can be horribly inefficient
[03:03:21] <maiden> Anniepoo_ been there done that.
[03:03:36] <Anniepoo_> the snail I'm building has about the same level of complexity, and many of the same requirements, as the R-25 I worked on at Robokind
[03:04:31] <maiden> are tempted to apply for a new job att ABB corperate research as they have a lot of cool titles and projects, but i know how it is to work at a large organisation and that puts me off a lot.
[03:04:31] <Anniepoo_> I've gotten significantly further with about $500 in parts and probably 60 hours of work than we did in the year I was at Robokind with a headcount of 12 or so.
[03:05:07] <SpeedEvil> Anniepoo_: communication is a bitch
[03:05:22] <Anniepoo_> most of it is that RK undervalued the already well trodden path
[03:05:32] <SpeedEvil> yeah.
[03:05:37] <SpeedEvil> You're a teeny company.
[03:05:52] <Anniepoo_> They were using some ARM Cortex-M4 custom board,
[03:05:54] <SpeedEvil> Don't spend the tiny workforce you have replicating badly stuff that was worked on in teh 60s
[03:05:58] <SpeedEvil> (for example)
[03:06:14] <Anniepoo_> and yes, communication's an incredible bitch
[03:06:25] <Anniepoo_> I'm using a Raspberry Pi 3
[03:06:27] <SpeedEvil> You'll never have something optimised well at that size of company, so accept 'good enough' and move on
[03:06:32] <maiden> PAL robotics looks interesting still ;)
[03:07:17] <Anniepoo_> the docs for the camera on this board took me over a month to decipher.
[03:08:50] <Anniepoo_> The PiCamera lib for the RPi3 took me about an hour of fiddling with and I've spent another 3-4 hrs mucking with alternatives to move the data to the stand off server
[03:10:21] <Jak_o_Shadows> Fairly recently I got a camera working on an ARM board
[03:11:19] <Anniepoo_> they wrote their own animation editor. I'm using blender, intending to write an exporter and tool that shows when I've exceeded acceleration/speed curves I'll get off the physical robot
[03:11:24] <SpeedEvil> I do wisht he Pi had a raw camera driver
[03:11:34] <Jak_o_Shadows> Anniepoo, that's pretty much what I would do
[03:11:44] <Anniepoo_> you can get the raw Bayer data from the camera
[03:11:51] <SpeedEvil> Tehre are eleventy billion fun cameras that could be attached.
[03:12:16] <Anniepoo_> it's available in the PiCamera lib
[03:12:40] <Anniepoo_> I don't know how much more raw you want to get
[03:12:54] <SpeedEvil> To be able to attach other cameras.
[03:13:02] <SpeedEvil> (CSI bus, two lane)
[03:13:20] <Anniepoo_> I wish I could attach more than one camera
[03:13:29] <Anniepoo_> just to switch them
[03:13:43] <SpeedEvil> There is an evil hack.
[03:13:54] <Anniepoo_> I probably just would have to figure out which of a few lines to switch, but meh...
[03:13:59] <Anniepoo_> whats the hack?
[03:15:20] <SpeedEvil> I can't find the auction - it's a mirror and periscope arrangement - they sell them for phones for $5
[03:15:36] <SpeedEvil> Advantage is it's inherently synced
[03:15:46] <Anniepoo_> right
[03:16:01] <SpeedEvil> http://www.ebay.co.uk/itm/Mini-3D-Stereoscopic-Camera-Lens-w-Clip-For-iPhone-Samsung-Smart-Phone-/152236105326?hash=item2371fa9e6e:g:n6kAAOSwgmJX00a6 ah
[03:16:04] <Anniepoo_> hmm... hadn't thought of doing it optically
[03:16:26] <SpeedEvil> Now, I wouldn't expect it to be awesome optically.
[03:16:59] <Anniepoo_> I dont' want stereo
[03:17:02] <SpeedEvil> oh
[03:17:16] <Anniepoo_> I want different cameras for different pieces of sensorium data
[03:17:36] <Anniepoo_> one in head, one in body
[03:18:50] <Anniepoo_> incidentally, I bet this conductive Graphene filament is thermally conductive too
[03:19:16] <SpeedEvil> Unlikely - it's probably going to be dominated greatly by the plastic
[03:19:31] <SpeedEvil> If you mean 'better than plastic' - sure
[03:20:03] <Anniepoo_> electrical conductivity and thermal conductivity are often related
[03:20:34] <SpeedEvil> yes. But absolute values are often small
[03:21:28] <jrowe47> yeah, graphene infused plastics are showing neat properties
[03:21:30] <jrowe47> http://www.nature.com/articles/srep26825
[03:21:57] <jrowe47> starting to get materials that are cheap with novel engineering properties
[03:22:38] <Anniepoo_> betcha betcha the pricey coolpoly stuff I've got is just this stuff
[03:23:09] <Anniepoo_> it looks kind of a gun finish grey,
[03:23:29] <Anniepoo_> bet it's just graphene impregnated plastic
[03:23:47] <jrowe47> graphene would be carbon black for anything over 30%
[03:24:33] <jrowe47> just like putting activated carbon into something - gunmetal gray could be a ocmbination of graphene, silver nanowires maybe
[03:26:32] <jrowe47> does it conduct electricity?
[03:27:11] <Anniepoo_> hmm... I don't have it here, it's at the shop, I'm at home
[03:27:29] <jrowe47> ahh
[03:28:04] <jrowe47> fun stuff to have
[03:29:37] <SpeedEvil> Graphene is not cheap enough to be put into bulk products AIUI
[03:29:45] <jrowe47> sure it is
[03:29:52] <SpeedEvil> If you're buying a kilo of stuff and not experiencing sticker shock, it's got little graphene in it
[03:29:59] <jrowe47> graphene nanoplatelets are trivial to produce
[03:30:27] <SpeedEvil> $?/kg
[03:30:32] <jrowe47> its the macro structures that are being chased, what we've got so far is enough for some interesting things
[03:31:26] <jrowe47> the cost of graphite, strong electrolyte solutions, ultrasonic cleaners, a good stainless steel electrode, and electricity
[03:31:52] <jrowe47> can get a good solution of micron sized graphene platelets
[03:31:53] <SpeedEvil> That doesn't say anything about yield.
[03:32:21] <jrowe47> the graphite is converted into nanoplatelet graphene
[03:32:29] <jrowe47> so the yield is however much graphite you put in
[03:32:31] <SpeedEvil> At what rate.
[03:32:42] <jrowe47> on the order of kilograms per hour for a home based setup
[03:32:43] <Anniepoo_> I looked at some youtube videos
[03:32:50] <SpeedEvil> Interesting.
[03:32:55] <Anniepoo_> and yes, it seemed dead simple
[03:33:25] <Anniepoo_> the one I watched was epsom salts, two mechancial pencil leads, and a 9v transistor battery
[03:33:27] <jrowe47> theres just not much you can do with the platelets beyond infusing plastics and other stuff that isn't really helpful in a garage science way
[03:34:10] <jrowe47> yup, but its critical to put them in an ultrasonic chamber to get them to separate to 1-2 layer platelets
[03:34:31] <jrowe47> otherwise you get a low percentage of actual graphene, and lots of tinky graphite flakes
[03:34:46] <Anniepoo_> ok, I can buy an ultrasonic cleaner at harbor freight
[03:34:55] <jrowe47> yeah, taht'd do the trick
[03:35:02] <SpeedEvil> jrowe47: Do you have a link to 'kilos an hour' ?
[03:35:18] <Anniepoo_> (and I'd point out that for making a conductive plastic it'd probably not matter if it was 3 molecules thick, not one)
[03:35:22] <SpeedEvil> Ideally with some charechterised product
[03:35:46] <jrowe47> https://www.youtube.com/watch?v=hFUOsZ0LSkQ
[03:36:22] <jrowe47> Anniepoo_, i guess it does matter past 3 layer, it starts to lose its properties?
[03:36:24] <jrowe47> strange stuff
[03:36:34] <jrowe47> that guy's got a good channel, btw
[03:37:45] <jrowe47_afk> have a good night!
[03:42:43] <SpeedEvil> jrowe47_afk: I failed on a quick look to find a paper or ohter source for any analysis of the flakes.
[03:43:29] <SpeedEvil> https://cen.acs.org/articles/92/web/2014/04/Solution-Graphene-Production.html
[03:43:48] <SpeedEvil> ah
[04:01:03] <Jak_o_Shadows> Hmm. For those parallel interface cameras, you can disable the analogue circuitry sometimes, and just not give it a clock
[04:01:21] <Jak_o_Shadows> Dunno if it'd work. The signal may be push-pull
[05:59:40] <maiden> jrowe47: nice link, subscribed to the channel, now i need a chemistry lab as well...
[14:14:08] <artg02> hey all :)
[14:14:09] <mrdata> howdy
[14:14:32] <artg02> so again for clarity
[14:14:33] <artg02> I am looking for some info about "classification of control engineering systems"
[14:14:33] <artg02> its one of the topics of my professor, but I dont understand shit of it :)
[14:15:05] <artg02> basically the topic is "system classification" but its all very vague (as normal on my university)
[14:15:22] <mrdata> https://en.wikipedia.org/wiki/Control_engineering
[14:15:23] <mrdata> https://en.wikipedia.org/wiki/Control_system
[14:16:33] <mrdata> you'll find lots of stuff in those wiki articles; including the see also section
[14:17:13] <mrdata> artg02, or do you have a more specific question?
[14:17:43] <artg02> well they say stuff like "when the system is of type 0 then this"
[14:17:54] <artg02> but what is a type 0 system for example?
[14:18:50] <mrdata> hmm
[14:19:19] <artg02> I can post the pfd of my university if that helps?
[14:19:25] <artg02> *pdf
[14:19:27] <mrdata> http://www.ee.usyd.edu.au/tutorials_online/matlab/extras/ess/ess1.html
[14:20:39] <mrdata> more specifically
https://www.ee.usyd.edu.au/tutorials_online/matlab/extras/ess/ess.html
[14:22:19] <mrdata> http://aerostudents.com/files/controlTheory/controlTheoryFullVersion.pdf
[14:22:39] <mrdata> http://www.pages.drexel.edu/~pyo22/mem639/lecture07-SystemIdAndPid/pidTheory.pdf
[14:23:16] <mrdata> my understanding is a bit vague on these, but i think the last two links define type 0 adequately
[14:24:47] <artg02> thanks, let me read those first
[15:30:15] <z64555> jrowe47_afk: how fast are those nylon muscles?
[17:07:26] <delinquentme> http://pdf1.alldatasheet.com/datasheet-pdf/view/533697/MACOM/PEOSSDO3A.html I've got this datasheet. Page 3 seems to indicate that Pin A ... <> Live
[17:07:30] <delinquentme> or am I high?
[18:14:32] <rue_house> hmm
[18:16:10] <rue_house> PIN A is hot, aka live
[18:16:20] <rue_house> pin D is neutral, aka ground
[18:50:55] <jrowe47> rue_house, how are ya
[18:51:47] <jrowe47> thought through that 3 actuator / 2 axes of motion, the only thing i could come up with was a single linkage controlled by an actuator
[19:02:17] <z64555> neutral != ground, when talking about AC systems
[19:03:28] <z64555> American split-phase AC ties the neutral line to the center tap of the transformer
[19:03:46] <z64555> so you can get 110 and 220VAC
[19:05:44] <z64555> in very old AC devices, the ones without a polarized plug, many times the case would be grounded to one of the lines
[19:06:21] <z64555> In the operator and service manuals, they'd suggest plugging it in, lightly brush a finger across the top of the case to see if it "tickles"
[19:06:34] <z64555> If it does tickle, then flip the plug around
[19:07:42] <z64555> (those had the neutral as ground, and was only 110VAC)
[19:13:21] <jrowe47> just lick it a little
[21:30:36] <rue_house> jrowe47, how many axies on a plane?
[21:30:50] <jrowe47> 2
[21:30:58] <Wayward> how many snakes on a plane?
[21:31:07] <jrowe47> motherf***ker
[21:31:19] <jrowe47> lol
[21:31:46] <rue_house> any so it takes 4 cables, 2 complimentrary to tip X and 2 complimentrary to tip Y right?
[21:32:03] <jrowe47> ok
[21:32:38] <jrowe47> so offset the actuators by 120 degrees around the edge
[21:32:40] <Wayward> or 3 and good math
[21:33:12] <jrowe47> combination of 3 actuators gets you the same range as 4 with 90 degree intervals
[21:44:40] <z64555> plot a force distribution for a given tilt angle
[21:45:25] <z64555> for both the 4 actuator and 3 actuator combinations
[21:47:00] <z64555> It'll likely turn out to be a polygon inscribed by a circle
[21:47:20] <z64555> err, a polygon inside a circle
[21:47:39] <jrowe47> with a slight inward curve to the edges of the polygon
[21:47:43] <z64555> Circle representing the maximum possible force vector, and the polygon represting the maximum achievable
[21:48:23] <jrowe47> i think it'd be better for this to have a coil connected to opposing inner and outer rims
[21:48:33] <jrowe47> more bend
[21:49:13] <jrowe47> and then alternate them in a helix
[21:50:33] <jrowe47> if i printed in a tough nylon, then the support structure would last as long as the coils, and would likely be very low friction
[23:35:44] <rue_shop3> its a point that at this point I should be able to catalogtize my shop operations
[23:36:44] <z64555> organize section in terms of fun! :D
[23:37:39] <z64555> "Fun Station" "Dangerously Fun Station" and "Really Fun but Really Broken"
