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[01:25:01] <rue_shop3> yay I made a foot switch for the drillpress
[01:25:21] <Anniepoo__> 8cD
[01:25:39] <Anniepoo__> that's a good idea, though it should have a proper safety guard
[01:31:06] <rue_shop3> oh, I skipped that
[01:31:33] <rue_shop3> I'm more caught up in what to use for connectors from it to the DC brake module
[01:32:14] <rue_shop3> I think this DC brake module has been sitting here for like 12 years
[01:32:19] <rue_shop3> :/
[01:32:32] <rue_shop3> In 12 years it'd have saved me a lot of time
[01:33:10] <Anniepoo__> I'm just concerned for your safety. easy to accidentally step on a foot switch with hands in the way of nasty rotating thingies
[01:34:21] <rue_shop3> might be why I got the one from china so cheap
[01:35:22] <Anniepoo__> make a wood box with one side missing, put inside
[01:35:23] <rue_shop3> I think I'll use 1/4 phono
[01:35:35] <rue_shop3> 11pm and I need food
[01:35:39] <rue_shop3> who should I eat
[01:35:41] <Anniepoo__> 8cD
[01:35:46] <rue_shop3> er, wonder what I should eat
[02:36:42] <jrowe47> so if nylon coils contract when they heat up, do they cool down when you stretch them back?
[02:36:56] * jrowe47 showerthoughts
[02:37:13] <jrowe47> because i irc in the shower
[02:41:14] <rue_house> no
[02:41:47] <rue_house> the distortion actually causes them to heat up
[02:58:42] <jrowe47> hmm
[02:59:12] <jrowe47> then its absolutely necessary to use liquid cooling
[02:59:55] <rue_house> Because of magnetic saturation, there is no advantage to increasing the current to more than 2 times the rated current and doing so may damage the motor.
[02:59:57] <rue_house> ""
[03:00:02] <jrowe47> i just got some super tough nylon filament to print the housing for the actuator
[03:00:26] <jrowe47> now im learning about how much i dont know about hydraulics
[03:01:01] <jrowe47> and thermal conduction
[03:01:16] <rue_house> http://www.nmbtc.com/step-motors/engineering/torque-and-speed-relationship/
[03:01:17] <rue_house> http://www.nmbtc.com/step-motors/engineering/torque-and-speed-relationship/
[03:01:17] <rue_house> http://www.nmbtc.com/step-motors/engineering/torque-and-speed-relationship/
[03:01:34] <rue_house> nothing to do with you, but a good article
[03:01:51] <jrowe47> neat
[03:02:56] <rue_house> http://www.nmbtc.com/hybrid-step-motors/part-numbering/
[03:03:02] <rue_house> that could come in handy too
[03:04:28] <rue_house> I cant count how many MNB steppers I have
[03:04:32] <rue_house> casue I'm not in the shop
[03:14:23] <rue_shop3> I'm starting to dream of a wall of 3d printers, and I can start each peice of a project printing as I design them
[03:14:45] <rue_shop3> I wonder how many printers I could occupy on a typical project
[03:14:53] <rue_shop3> I bet 4 easy
[03:15:08] * rue_shop3 works on his new cnc machine
[03:45:52] <jrowe47> https://www.youtube.com/user/RobertMurraySmith/videos - this guy goes over some really interesting graphene projects, making a conductive ink with suspended graphene flakes
[03:46:14] <jrowe47> he also shows the graphene over magnetic fields, it orients like iron filings
[03:46:44] <jrowe47> was thinking that a magnetic field could orient flakes in the solution at a high enough density to provide some crazy thermal conductivity
[03:47:50] <jrowe47> so instead of flowing fluid in my nylon muscle actuator, I could externalize the coolant loop, and place the actuators within the magnetic field lines over which the graphene orients
[04:18:05] <rue_shop3> oooh no
[04:18:10] <rue_shop3> I just figured it out
[04:18:17] <rue_shop3> I'm having an energy burst
[04:18:30] <rue_shop3> this happens when your immune system is going crazy
[04:18:37] <rue_shop3> I'm about to be ill for a while
[04:20:28] <rue_shop3> z axis for the new cnc weighs 2.2kg
[04:20:31] <rue_shop3> jeeesh
[04:39:47] <rue_house> http://ruemohr.org/~ircjunk/projects/cnc4/slide.htm
[04:55:29] <SpeedEvil> In those who qualified, acquisition of an internal spatial representation of London was associated with a selective increase in gray matter (GM) volume in their posterior hippocampi and concomitant changes to their memory profile. No structural brain changes were observed in trainees who failed to qualify or control participants. We conclude that specific, enduring, structural brain changes in adult humans can be induced by biologically relevant
[04:55:29] <SpeedEvil> behaviors engaging higher cognitive functions
[04:55:31] <SpeedEvil> oops
[05:47:10] <jrowe47> SpeedEvil, the connectome changed in those cabbies, scientists found physical structures correlated to physical routes in the maps
[05:47:38] <jrowe47> kinda neat that synapses can spatially encode representations
[06:38:18] <SpeedEvil> yeah
[06:38:36] <SpeedEvil> I want to see work on people who've not driven taxis for 5 years
[07:06:13] <transhuman> hi! I have a question for robots like these
http://www.superdroidrobots.com/shop/custom.aspx/custom-robot-arms/54/ how accurate in 3D space and 2D space is the motion of the robots? Is it down to millimeter, cm, micrometer?
[07:58:25] <jrowe47> 0.019 inches, based on their encoder page
[07:58:30] <jrowe47> http://www.superdroidrobots.com/shop/custom.aspx/encoder-support-page/73/
[08:02:17] <transhuman> jrowe47, do any of them get more accurate than this that are on wheels or tracks?
[08:02:33] <jrowe47> no clue
[08:02:39] <jrowe47> just poked around on their site
[08:03:21] <transhuman> I had an interesting idea, and wanted to see if it was viable, been looking at different ones but accuracy isn't readily published on many of them
[08:05:06] <transhuman> ah I see it has to do with how accurate the stepper motors are
[08:05:55] <jrowe47> yup
[08:06:07] <jrowe47> so increasing accuracy is just a matter of a better control and better servos
[08:08:09] <transhuman> thats great news I had an awsome idea, I think i can pull it off too
[08:17:03] <jhylands> Hey deshipu - you around?
[08:23:30] <deshipu> jhylands: how do I check?
[08:23:37] <jhylands> Have you seen this:
http://www.digikey.ca/product-detail/en/stmicroelectronics/VL53L0CXV0DH-1/497-16538-1-ND/6023692
[08:23:56] <jhylands> it looks similar to the one sparkfun sells, but appears to have a range of up to 2m
[08:24:16] <deshipu> yes, I have it on order
[08:24:22] <deshipu> adafruit sells it on a breakout
[08:24:42] <jhylands> oh, nice
[08:24:52] <deshipu> I'm planning to write a driver in micropython for it once I get it
[08:25:03] <jhylands> sweet
[08:25:04] <deshipu> https://www.adafruit.com/products/3317
[08:25:05] <deshipu> here
[08:25:19] <jhylands> I'm about to change my new mini-sumo design to use it, I think
[08:25:29] <jhylands> its way better than any of the IR sensors I've used
[08:25:57] <jhylands> I think I'll have to make my own breakout though - they are out of stock
[08:25:58] <deshipu> yeah, reflective sensors are less reliable
[08:26:42] <deshipu> look for "gy-530"
[08:26:58] <deshipu> https://www.aliexpress.com/item/GY-530-VL53L0X-World-smallest-Time-o-f-Flight-ToF-laser-ranging-sensor/32728308376.html
[08:27:25] <jhylands> nice
[08:28:21] <jhylands> I may still make my own - I don't like only having a single mounting hole
[08:28:43] <deshipu> sure
[08:28:45] <jhylands> and I would prefer to use 1.25mm spacing plugs
[08:28:53] <jhylands> DF-13 from Hirose
[08:29:19] <deshipu> they are a bit hard to solder
[08:29:29] <jhylands> I have a reflow oven
[08:29:51] <deshipu> I had problems with the vl6180
[08:30:05] <jhylands> did you use a stencil?
[08:30:10] <deshipu> this one at least is for 3.3V
[08:30:13] <deshipu> not 2.8V
[08:30:18] <jhylands> yeah
[08:30:42] <deshipu> no, I used a siringe needle and a kitchen stove
[08:31:13] <deshipu> I tried to use the hot air gun at the fablab, but it would blow the part away
[08:31:37] <jhylands> yeah, using a stencil with a proper reflow oven makes it a lot simpler to do small parts like that
[08:32:26] <deshipu> I can imagine
[08:33:30] <jhylands> I regularly solder 6-TSSOP chips that way
[08:33:46] <jhylands> 0.65mm pitch
[08:34:31] <jhylands> the VL53 is 0.8mm
[08:34:41] <deshipu> easy-peasy
[08:34:44] <jhylands> heh
[08:34:55] <deshipu> the problem for me is not the pitch, but the fact that the pins are hidden on the bottom
[08:35:01] <jhylands> yeah
[08:35:06] <jhylands> the stencil helps with that
[08:35:10] <deshipu> how?
[08:35:18] <jhylands> you really have to limit the amount of solder paste on each pad
[08:35:32] <jhylands> otherwise you get shorts
[08:35:55] <jhylands> the stencil is cut to the paste mask, which is smaller that the pad itself
[08:37:18] <jhylands> here's a question for you - can you use multiple of these sensors, if they are facing the same direction, but separated by say 75mm?
[08:37:35] <jhylands> can you control the timing enough to avoid interference?
[08:38:39] <deshipu> no idea, I'm still waiting for mine, and I only ordered one
[08:38:48] <jhylands> looks like you can do single-shot
[08:39:08] <deshipu> sure
[08:39:24] <deshipu> it's actually multiple-shot, averaged
[08:39:37] <deshipu> and you can control how many measurements to take
[08:39:41] <jhylands> nice
[08:39:53] <deshipu> it does the integration on the chip
[08:40:09] <deshipu> at least that's how it was with vl6180
[08:40:18] <deshipu> but I doubt this one will be worse
[08:40:30] <deshipu> the problem is, there isn't really a proper datasheet for it
[08:40:51] <deshipu> we have some example init sequences, but no real explanation what all the registers are doing
[08:41:08] <deshipu> and there are like 20 of registers you have to set at startup
[08:43:14] <jhylands> there are a lot of docs here:
http://www.st.com/content/st_com/en/products/imaging-and-photonics-solutions/proximity-sensors/vl53l0x.html
[08:44:21] <deshipu> jhylands: well, it misses the registers
[08:44:25] <deshipu> jhylands: page 21
[08:45:01] <jhylands> looks like there is a sample code package that includes doxygen docs
[08:45:06] <jhylands> of the API
[08:45:11] <jhylands> might be worth checking
[08:45:34] <deshipu> yes, that's what I'm going to use to write the driver
[08:45:46] <deshipu> but it still doesn't tell you what all the registers are
[08:45:58] <deshipu> and I guess they don't plan to release such documentation ever
[08:46:10] <deshipu> which is a bit sad
[08:49:27] <jhylands> deshipu, did you look at the 157 page API doc that comes with the software?
[08:51:00] <jhylands> it lists all the registers, and appears to even say a bit about each
[08:51:54] <deshipu> cool, I will look at it once I'm working on it
[08:52:27] <deshipu> for now, I spent several hours yesterday debugging my servo controller code
[08:52:50] <deshipu> but I'm quite happy with it now
[08:53:22] <deshipu> there is still one way to make it behave weird, but I'm not sure if I want to add a check for it
[08:54:34] <deshipu> it only happens with duty cycles at the order of 1us
[08:55:48] <transhuman> those distance finders are interesting but I dont see any indication now accurate they are, anyone able to tell me?
[08:57:53] <deshipu> transhuman: 1mm resolution
[08:58:21] <deshipu> transhuman: there are some graphs in the datasheet
[08:58:49] <transhuman> 1mm hmm ok
[09:02:12] <transhuman> deshipu, is there any ...maybe larger that are more accurate maybe within .0005 inches? or is that not something that tech will do?
[09:02:35] <deshipu> no idea
[09:04:42] <deshipu> theoretically they can be accurate up the ~700nm
[09:05:03] <deshipu> maybe less, if they use deeper infrared
[09:05:24] <deshipu> but of course that would require very precise manufacturing
[09:05:37] <deshipu> and compensation for temperature and what not
[09:06:14] <deshipu> in practice, 1mm at 2m is already pretty good for a $10 sensor
[10:03:45] <transhuman> one last question: promise to leave everyone alone for the day this...
http://www.superdroidrobots.com/shop/custom.aspx/custom-robot-arms/54/ is there an open source project like this one?
[10:13:51] <deshipu> you mean an arm on tracks?
[10:14:12] <transhuman> yes
[10:14:45] <transhuman> I saw this ...seems very advanced though
https://en.wikipedia.org/wiki/InMoov and I wonder about accuracy for arm motions
[10:15:26] <deshipu> it's basically just a posing doll
[10:15:44] <deshipu> can't really do anything with those hands
[10:21:00] <transhuman> yeah thats what I figured deshipu
[12:19:30] <rue_house> http://www.nmbtc.com/hybrid-step-motors/part-numbering/
[15:20:29] <delinquentme> pdf1.alldatasheet.com/datasheet-pdf/view/533697/MACOM/PEOSSDO3A.html ... according to this data sheet ... page 3... pin D ... should be connected to neutral and pin A ... to hot right?
[15:20:41] <delinquentme> because what im seeing with my meter is just the opposite.
[15:20:58] <delinquentme> and these dont seem like cheap components ...
[15:53:40] <jhylands> Hey deshipu, not sure if you've seen it, but Pololu's code for the VL53L0X looks a lot simpler
[16:03:55] <deshipu> jhylands: yeah, I've seen it
[16:04:03] <deshipu> jhylands: I'm going to base my driver on that
[16:04:08] <jhylands> Good
[16:04:08] <deshipu> jhylands: thanks
[16:04:19] <deshipu> it will be another week probably
[21:34:17] <anniepoo> 8cD acoustic sensor running
[21:34:35] <anniepoo> every litter bit Hertz