#robotics Logs
Nov 23 2019
#robotics Calendar
04:37 AM fling_ is now known as fling
10:56 AM rue_bed: --
11:16 AM gartt: Hey Rue, have any experience with the Google G950-00866-01 AIY Vision Kit?
11:17 AM gartt: Advanced object recognition
11:17 AM gartt: I just came across this last night and was reading about it
11:23 AM rue_mohr: nope
11:23 AM rue_mohr: its been said I'm a low level guy and its too true
11:37 AM gartt: From seeing some of your project, I'd agree. But still pretty cool. Vision recognition has been maybe the biggest limitation in robotics over the years and now it's getting good
11:41 AM rue_mohr: you know about that new esp32 board right?
11:42 AM rue_mohr: with the face rec'g that I think is built into the camera?
11:51 AM gartt: I wouldn't know my own name if it wasn't written on my underwear. But I'll read about it
11:52 AM gartt: I don't care so much about face rec as object recognition
12:09 PM Zodiac is now known as Guest18941
01:57 PM wildmage: my channel
01:58 PM wildmage: what have you become
01:58 PM wildmage: well I've spent the last several years since I was on this channel working on understanding cortical algorithms
01:59 PM zhanx: wildmage, its dead due to the bot net attacks
01:59 PM zhanx: few of us still talk etc
01:59 PM wildmage: trying to understand how the brain represents space, makes decisions, and does the basic sensorimotor actions
01:59 PM wildmage: is that recent phenomena? or is that a long-standing problem
01:59 PM zhanx: going on for about 6-7 months now
02:00 PM wildmage: so the servers get DDoS'd and everything splits?
02:00 PM zhanx: i am working on a 3d printed multi-mix head for printing with cement right now
02:00 PM zhanx: no, they were spamming ads this time
02:00 PM zhanx: like nonstop
02:00 PM wildmage: @zhanx oh nice, are you familiar with Contour Crafting?
02:00 PM zhanx: nope
02:01 PM wildmage: @zhanx http://contourcrafting.com/
02:01 PM wildmage: they do 3D printing with concrete
02:01 PM wildmage: i did some initial work with these guys several years ago
02:01 PM wildmage: i have no idea how far along they are now
02:01 PM zhanx: yea ok, i saw that
02:02 PM rue_mohr: wild!
02:02 PM wildmage: i imagine printing cement is just as hard
02:02 PM zhanx: I am doing it different and smaller scale
02:02 PM wildmage: @rue_mohr hey Rue
02:02 PM wildmage: @zhanx any samples you can show?
02:02 PM rue_mohr: the thing the camera was used for was from nasa tho wasn't it?
02:02 PM zhanx: wildmage, think 50 pound bags of raw materials per hopper, no making test print head now
02:03 PM wildmage: @rue_mohr you remember… but no, it was for this contour crafting thing… before it was a company
02:03 PM zhanx: wildmage, my test head should be done in about a week
02:03 PM rue_mohr: cool
02:04 PM rue_mohr: haha
02:04 PM wildmage: @zhanx i think there's no small scale when it comes cement/concrete :)
02:04 PM rue_mohr: two problems with the last image on that page
02:04 PM rue_mohr: a) he's not using his phone to control it
02:04 PM zhanx: wildmage, true, i am doing 1 meter scale
02:04 PM rue_mohr: b) its only a single dwelling, not octal
02:05 PM rue_mohr: or more
02:07 PM rue_mohr: I wonder tho, concrete is $110/m^3
02:08 PM rue_mohr: I think
02:08 PM rue_mohr: might be higher now
02:08 PM wildmage: i'm working with grid cells right now
02:08 PM wildmage: not robots, but brain representation of space
02:08 PM zhanx: rue_mohr, you have email
02:08 PM rue_mohr: w/concrete?
02:08 PM rue_mohr: oh
02:12 PM rue_mohr: ah yes
02:13 PM rue_mohr: what you gonna make it from?
02:13 PM zhanx: aluminum
02:13 PM rue_mohr: k
02:13 PM zhanx: test fit was about perfect on it
02:13 PM rue_mohr: so, that clay extruder
02:13 PM zhanx: yep
02:13 PM rue_mohr: you notice the taper they put on it?
02:13 PM zhanx: yes
02:13 PM rue_mohr: I thought that was interesting
02:14 PM zhanx: I will be doing that for the main feed to the head
02:14 PM rue_mohr: squeeze out bubbles?
02:14 PM zhanx: yep
02:14 PM rue_mohr: hm
02:14 PM zhanx: i will have 3 funnels in the system also
02:14 PM rue_mohr: have you worked out flow/deposit rates?
02:14 PM zhanx: not yet
02:15 PM zhanx: i have an idea, but
02:15 PM zhanx: I am shooting for 20mm/s
02:15 PM rue_mohr: well, what extrusion size you targeting?
02:15 PM rue_mohr: 10mm?
02:15 PM zhanx: 2mm thick, 24mm wide
02:15 PM rue_mohr: 25mm?
02:15 PM rue_mohr: oh
02:16 PM rue_mohr: rectangular
02:16 PM rue_mohr: so your doing the vector thing?
02:16 PM zhanx: yep but I plan to have options if needed for round
02:16 PM zhanx: well vector seems easier to start with
02:16 PM rue_mohr: hmm
02:16 PM zhanx: the rest will be redneck engineering
02:17 PM rue_mohr: 4 axis plotter
02:17 PM wildmage: @zhanx i've heard that controlling the rate of flow of the mix is a real challenging problem
02:17 PM zhanx: wildmage, yep
02:17 PM zhanx: gonna be more fun as my mix will have 5 motors to make it
02:20 PM rue_mohr: I have a bit more to fix on the new 3d printer before I can run it in, and then convert it to wax/chocolate/paste/silicone/(sugar)
02:20 PM rue_mohr: the Y axis has 0.4mm backlash, that isn't backlash
02:20 PM zhanx: rue_mohr, i might just order the filament to cast with once all the prototyping is done
02:20 PM rue_mohr: it got scaled up too much, the y rails are flexing as its run back and forth
02:21 PM rue_mohr: I wonder if I can extrude that machinable wax I made
02:21 PM rue_mohr: I wonder what size nozzel you use for making 1.75mm filament
02:21 PM rue_mohr: hmmmm
02:22 PM zhanx: 1.80?
02:22 PM veverak: 1.7
02:22 PM zhanx: you know it will shrink
02:22 PM rue_mohr: It'll falre out
02:22 PM rue_mohr: so veverak is probably closer
02:22 PM rue_mohr: flare
02:23 PM rue_mohr: I'd think
02:23 PM rue_mohr: I dont even know if its got enough flex to withstand being coiled
02:23 PM zhanx: you know who to ask? crunch on #reprap, he makes atomic filament
02:24 PM rue_mohr: I'll get the machine working
02:24 PM rue_mohr: for my wax printing part, I'm just gonna use a reservoir
02:30 PM zhanx: wildmage, question
02:30 PM zhanx: how much energy does the brain use at rest vs thinking
02:30 PM Maya-sama is now known as Miyu
02:30 PM Miyu is now known as hackkitten
02:31 PM rue_mohr: 5-10w comes to mind...
03:13 PM zhanx: ok test nozzle is almost done
03:13 PM zhanx: had to reprint the funnel it
04:15 PM zhanx: rue where did i put that threaded rod?
04:36 PM flyback: <flyback> https://www.goldmine-elec-products.com/prodinfo.asp?number=G20206
04:36 PM flyback: <flyback> these are normally $25
04:36 PM flyback: <flyback> this model is special
04:36 PM flyback: <flyback> it's unreasonable good at reading CANUCKED UP discs
04:38 PM flyback is now known as phlyback
04:39 PM phlyback is now known as flyback
04:41 PM zhanx: weee
04:41 PM zhanx: my design is fitting together!
04:43 PM rue_mohr: :)
06:08 PM chisight: would love to see it too zhanx
06:09 PM zhanx: https://imgur.com/a/kg6VXmx
06:09 PM zhanx: https://imgur.com/a/qKgEgqw
06:09 PM zhanx: need to take more tomorrow when i have more light
06:13 PM chisight: ty :-)
06:13 PM zhanx: welcome
06:17 PM chisight: are you using a peristaltic pump like they use in medical devices to get precise flows?
06:20 PM zhanx: augers with water metering via peristaltic
06:22 PM chisight: ahh, just figured that concrete pumps are sometimes (often?) peristaltic pumps that it would make sense. it's also pretty precise as long as there is no large aggregate to prevent the hose from fully compressing.
06:22 PM logb0t_ is now known as logb0t
06:23 PM zhanx: well i need to mix different materials and the output will be concrete
06:25 PM chisight: the auger makes sense to get it to the hopper for mixing.
10:01 PM SpeedEvil is now known as Guest67766
11:10 PM zhanx: ugh
11:11 PM zhanx: chisight, i will be measuring auger output also for weight
11:13 PM chisight: zhanx: i assume checking it for moisture and the air's humidity. either that or checking slump somehow. i know cement is really picky and this is a precision application.
11:13 PM zhanx: yep, sensor madness
11:14 PM chisight: fun
11:14 PM zhanx: well with a 2mm thick 24 mm wide layer is has to be
11:14 PM chisight: are you heading the moisture sensor path or the slump path?
11:15 PM zhanx: both
11:15 PM chisight: sweet.
11:15 PM zhanx: I need to make sure the slump path is end goal but check before it etc
11:15 PM chisight: the first 2mm is easy, it's the 12th that is hard. that first layer has to set by then.
11:16 PM zhanx: speed x mix x ugh
11:16 PM chisight: yeah, i assume something like a quickcrete.
11:17 PM zhanx: custom mix but yea
11:17 PM chisight: hard task.
11:17 PM zhanx: but worth it
11:17 PM chisight: yeah.
11:17 PM zhanx: chisight, low g prints
11:18 PM zhanx: nothing is premixed so it can be used in remote places
11:18 PM chisight: so 1inch wide, what can you make with that? or do you plan to make multiple width?
11:18 PM zhanx: multiple width and head
11:18 PM chisight: i imagine 1" shell and 20% infill would be really cool.
11:19 PM zhanx: hint one of the augers will have fiberglass in it
11:19 PM chisight: if the 20% is set up to make air pockets, it would make a sweet combination of thermal mass and insulation.
11:20 PM chisight: how big a build area?
11:20 PM zhanx: chisight, if done right it could built a house yes
11:20 PM zhanx: right now 1 meter
11:20 PM zhanx: its proof of concept
11:21 PM chisight: i would love a house printed. though it needs embedded something to be able to screw into. and rebar could be hard.
11:21 PM zhanx: no rebar
11:21 PM chisight: screw into for things like mounting siding or drywall.
11:22 PM zhanx: spool of wire
11:22 PM zhanx: for the siding or drywall glue slates to the outside
11:23 PM chisight: ahh, glue is acceptable if the print cost is low enough.
11:24 PM zhanx: yep
11:25 PM zhanx: if this works out then its being scaled to 10 meter cubed
11:25 PM chisight: i imagine even 1m cube could make things of value. the equivalent of custom castings.
11:25 PM zhanx: it will yes
11:26 PM zhanx: pizza oven!
11:27 PM chisight: lol, nice
11:28 PM zhanx: really tho, it could make just about anything
11:28 PM Tom_L: zhanx you ever finish your easy bake oven?
11:28 PM zhanx: its on the self, it kind of works
11:29 PM Tom_L: the smelting thing..
11:29 PM zhanx: oh yea, a while ago
11:29 PM zhanx: thought you meant the reflow oven
11:29 PM Tom_L: oh i didn't know you were making one of those
11:29 PM zhanx: side thing, the pid is off a bit
11:29 PM Tom_L: mine's sitting on a shelf idle
11:29 PM zhanx: its in case i need it
11:30 PM chisight: anything that can handle the 2mm layer height and not care about that resolution.
11:30 PM zhanx: chisight, its concrete, 2mm is fine for it, and easy to clean up
11:31 PM zhanx: Tom_L, i need to spend a day smelting muffins soon, got a ton of stuff to melt down now
11:31 PM chisight: i was just thinking about 1m^3 concrete things that exist. things like statues or flowerpots. obviously bricks wouldn't be worth this effort.
11:31 PM zhanx: bricks would cost to much i think
11:32 PM chisight: yeah, wouldn't be worth this effort.
11:32 PM zhanx: chisight, one thing the large scale needs to print is biodigesters
11:34 PM zhanx: the 1 meter cube will print test designs
11:34 PM chisight: interesting application choice. but i imagine that is an appropriate thing to make 3d.
11:35 PM zhanx: well its what started this whole thing
11:36 PM chisight: ahh
11:37 PM zhanx: my buddy is doing them etc, the hard way
11:37 PM chisight: it's a good thing to have. not sure if the amount of waste my family makes is enough to even make cooking gas though.
11:37 PM zhanx: I was like well, let me show you the new way to make stuff
11:37 PM chisight: would make a good dent though.
11:38 PM zhanx: this is for villages etc in 3rd world
11:38 PM zhanx: and he is not very technical so
11:38 PM zhanx: it has to be easy
11:38 PM chisight: ahh, cool application.
11:39 PM zhanx: i was gonna opensource the printer, but man i have a lot of hours into it
11:41 PM chisight: i was thinking rather than the complexity of trying to be 100% right with moisture inputs, that batching the mix and doing slump testing along the way would be cheap and reasonable.
11:41 PM chisight: but clearly you have a lot more experience in this than i do.
11:42 PM zhanx: chisight, issue is people that don't know how to test
11:42 PM zhanx: so its a load and go thing
11:43 PM chisight: mix, push some of the mix up through a hole, monitor how long it takes to fall below a optical sensor. then push the whole thing over back into the mixing tank. add misted water and mix again. rinse repeat.
11:44 PM zhanx: close
11:44 PM zhanx: too much air in that
11:45 PM chisight: shouldn't the air be pretty consistent mix to mix?
11:45 PM chisight: therefore only consistently impacting slump
11:46 PM zhanx: once i get it done i will break down the why for you so you can see it
11:46 PM chisight: cool
11:46 PM zhanx: remember i need a consistent print layer right?
11:47 PM chisight: the air removal would be after the slump testing.
11:47 PM zhanx: and that is why it fails
11:48 PM chisight: i assume you know this better than i do but not following.
11:49 PM zhanx: chisight, been testing for 6 months now is all
11:49 PM zhanx: hand mixing etc
11:50 PM chisight: a slump with x air is equivalent to b slump with y air. x air is pretty consistent mix to mix so has little to no impact on the water content needed to get a final slump once air is reduced to y.
11:51 PM chisight: or does ongoing mixing entrain more and more air?
11:51 PM zhanx: then force that mix through small holes and test
11:51 PM chisight: the small holes is part of the air removal, right?
11:52 PM zhanx: yes
11:52 PM zhanx: basically end goal is of course same mix no matter what
11:52 PM chisight: i guess you could do that pre slump test. then scrap the test back into the mixing bin to further adjust the water content.
11:53 PM zhanx: or add heat to it
11:53 PM chisight: yeah, understood you want a mix at 90% humidity to perform the same as a mix at 20% humidity.
11:54 PM chisight: hmm, no clue on the impact of adding heat to concrete. i know it heats as it cures but not much past that.
11:54 PM zhanx: once my test is working I have an engineer coming over to help finalize it
11:54 PM zhanx: he works in concrete etc
11:55 PM chisight: good. i assume sending samples to be crush tested too.
11:55 PM zhanx: oh yea
11:55 PM chisight: interesting project.