#robotics Logs
May 10 2018
#robotics Calendar
12:06 AM rue_mohr: AchiestDragon, why dont you use a fet for the fans?
12:10 AM rue_mohr: AchiestDragon, hey, no wait no, dont use lienar regulator for the 5V!
12:10 AM rue_mohr: hey your on batteries, you need to be more conservative
12:10 AM rue_mohr: oh geeee
12:11 AM AchiestDragon: 5v supply is rpi , pwm board power , ardruino power and 2 aux usb power feeds so around 5a should be safe bet although it can do more
12:12 AM rue_mohr: at 5A your wasting 10W in heat
12:12 AM rue_mohr: 40% efficiency
12:13 AM rue_mohr: er, 60% but still, tahts horrid
12:15 AM AchiestDragon: theres current limiting in that also
12:15 AM rue_mohr: I know
12:15 AM rue_mohr: at 25W your losing 10W to *just* heat
12:16 AM z64555: so your getting half the available battery life
12:16 AM z64555: well, more than half, but just around there
12:16 AM rue_mohr: if you use a switching supply for the regulation, you can have the efficiency around 85-90%
12:17 AM rue_mohr: basically doubles your battery capacity
12:17 AM z64555: Unless you don't really care about swapping out batteries frequently
12:18 AM rue_mohr: I hope I dont seem like a jerk for saying I think your circuits should be totally different ;)
12:18 AM rue_mohr: I'm a jerk just cause I want to be.
12:18 AM AchiestDragon: i know but i would end up using around of the 3A swiching regulators
12:18 AM AchiestDragon: for the 5v
12:18 AM rue_mohr: even if you use 2 switching regulators, your better off
12:20 AM AchiestDragon: and theres 18 servos on the 6v power
12:20 AM rue_mohr: yupm I used 3 regulators on my bot
12:29 AM AchiestDragon: yea nad a fet for the fan control good idea
12:30 AM rue_mohr: did you test the mtoor driver?
12:34 AM AchiestDragon: yea, been sat meatring one of the old controlers and checking all the levels , etc , so now i got the logic right anyway
12:35 AM rue_mohr: wow, I started this program for generating state machines in 2006
12:35 AM rue_mohr: nowonder its not got my equation code in it
12:37 AM AchiestDragon: but got to have a play with one of the current limiting circuts before i try the high current motors , so i dont risk blow the hbridge fets with overcurent stall torque
12:38 AM AchiestDragon: or have to contend with exploading batteries
12:40 AM z64555: they shouldn't explode on discharge cycles
12:43 AM AchiestDragon: depends on discharge current , and battery temp , they can if the ouput is a vertual short ie a potential of 18 X 65a per motor current at stall torque
12:45 AM AchiestDragon: and if not the batteries i dont want it buring out the cables and tracks
12:48 AM AchiestDragon: nothing worse than it working then suddenly you find it busrts into flames as the insulation on its power lines melted and shorted out
12:53 AM AchiestDragon: i may still change the 29.6v suply , split it inot 3 and use 6* 4cell lipos 2 per bank so i get better current balance and maybe a bit more AH , but not priced up the batteries yet other than it will prob be arround £120+ for a set
12:58 AM AchiestDragon: as that would give me about 30a per bank max with the current limiting , at least i dont then have to wory about having to use higher current cables
01:02 AM AchiestDragon: or a 100a power swich ,, could uses a 3phase 35a contactor with a 12v coil for motor power isolation
01:03 AM rue_mohr: heavy and power hungry
01:03 AM rue_mohr: fuses are light and pretty power efficient
01:03 AM rue_mohr: your axies aren't back drivable
01:04 AM AchiestDragon: well at least that way besides the manual isolation swich i can logic swich the motor power , having a seperate 11.2v battery for that and the fans , should not be too bad
01:05 AM rue_mohr: my 12' mecha is only planned to weigh a tonne, and its made of steel, yours is 3d printed
01:08 AM rue_mohr: @#$%$%^&@#%$ I cant think anymore
01:12 AM zhanx: rue_mohr: and to think mine will be cast and weigh a 1/4 of yours
01:12 AM AchiestDragon: need to go shopping for cat food , run out the cat will go mental if i have no food for it , count down to next cat feeing is around 3hrs
01:12 AM rue_mohr: I dont know for sure how much mine will weigh, I'm just hoping to keep it under 07 kg
01:12 AM rue_mohr: 907kg
01:12 AM rue_mohr: damnit I need cat food too
01:12 AM zhanx: rue_mohr: you are looking at it wrong
01:12 AM zhanx: said it before
01:12 AM zhanx: bird bone structure out of modern materials but harder to make
01:13 AM rue_mohr: yea, easier to do in 0g
01:13 AM zhanx: yep or cast
01:13 AM rue_mohr: how do you foam aluminum at 1G
01:13 AM rue_mohr: ?
01:14 AM zhanx: in sand
01:14 AM rue_mohr: I want to understand now, but I have to go to sleep
01:14 AM rue_mohr: get me an image update on the printer eh?
01:15 AM zhanx: ok
01:15 AM zhanx: wait fgor it?
01:15 AM rue_mohr: ok
01:17 AM zhanx: https://imgur.com/a/GSwpc4S
01:17 AM zhanx: little busy
01:17 AM AchiestDragon: rig a mig up to a 3d printer frame , so it weld prints it in 3d in metal so you can get a infill type structure to it , like bird bones , and make the outer more of a mesh than a solid , even lighter
01:19 AM AchiestDragon: or a tig welder for aluminium
01:19 AM zhanx: rue_mohr: progress
01:20 AM zhanx: AchiestDragon: been making this printer for a year now
01:20 AM rue_bed: hah, ok, yea, needs some parts
01:20 AM zhanx: some but most are there
01:21 AM rue_bed: cool
01:22 AM rue_bed: We dont cross paths as much as I thought
01:22 AM rue_bed: maybe its just an insane time of year
01:22 AM zhanx: only need 3 more parts * I think *
01:22 AM rue_bed: which ones?
01:22 AM zhanx: bed and 2 collars for x axis
01:22 AM rue_bed: the hobbed bolt
01:22 AM zhanx: nope i made a second one
01:22 AM rue_bed: glass or subbed
01:23 AM zhanx: subbed
01:23 AM AchiestDragon: https://drive.google.com/file/d/1WFquJXt9Y46myXbNoDi4nfmDVwrtaEIE/view?usp=sharing < my home made 3d printer , need to get around to fixing it , but have a tevo delta now
01:23 AM zhanx: still have not got to it
01:23 AM rue_bed: k, 1/8" aluminum plate works
01:23 AM rue_bed: just about 12cm x 20cm
01:23 AM zhanx: k
01:23 AM rue_bed: 20? 30?
01:24 AM zhanx: i got some 1/4 plate coming might use a cut off of that
01:24 AM zhanx: but that is steel
01:24 AM rue_bed: steel is ok
01:24 AM rue_bed: alum is easier
01:24 AM zhanx: re skid plating my toy
01:24 AM rue_bed: heh
01:24 AM rue_bed: it survived the storm?
01:25 AM rue_bed: how did the car do?
01:25 AM zhanx: yep, car not so god
01:25 AM zhanx: good
01:25 AM rue_bed: hmm
01:25 AM zhanx: insurance is painting it
01:25 AM rue_bed: .... windows were ok?
01:25 AM zhanx: 3 being replaced
01:25 AM rue_bed: or they just gonna paint them...
01:25 AM rue_bed: :)
01:26 AM zhanx: i am mad tho, no apple tree replacement
01:26 AM zhanx: i lost 3 of them
01:26 AM rue_bed: ouch
01:26 AM rue_bed: ~$300?
01:26 AM zhanx: 4 year olds
01:26 AM zhanx: so more
01:26 AM rue_bed: they do any apples yet?
01:27 AM zhanx: got a gut that say he cab graft the roots tho
01:27 AM rue_bed: he?
01:27 AM rue_bed: oh guy
01:27 AM zhanx: rue_bed: did you forget last years cider?
01:27 AM rue_bed: yup
01:27 AM zhanx: i made 10 gallons of it
01:27 AM rue_bed: 4 isn't that old
01:28 AM zhanx: no but still covered i thought
01:28 AM zhanx: i did get the rest of the potatoes in today
01:28 AM rue_bed: lost 3/3?
01:28 AM zhanx: and turn the other beds
01:28 AM zhanx: yep 3/3
01:28 AM rue_bed: ouch
01:29 AM zhanx: it was 75.2 mph winds
01:29 AM zhanx: luck that was all
01:29 AM rue_bed: I wish I could have a plumb tree, the animals would take it aapart
01:30 AM rue_bed: the bear pulls down what the deer cant reach so that they can eat everthing
01:31 AM zhanx: bears lay on my fence
01:31 AM rue_bed: gnight
11:00 AM kastar is now known as LennyCrawfish
01:52 PM Atomsk is now known as ace4016
01:53 PM SpeedEvil: Is anyone aware of 'mundane' attempts to do regular stuff with industrial robots?
01:53 PM SpeedEvil: I mean telepresence wise.
01:54 PM SpeedEvil: Assembling Ikea furniture, for example.
02:32 PM durrf: you mean like what simone giertz did with the kuka robot?
03:24 PM SpeedEvil: I was more meaning rather than the typical teleoperation demos 'watch me place this egg into this cup' - something more involved, but still basically using commodity hardware
07:56 PM ace4016: you mean in a non-industrial setting?
08:05 PM rue_mohr: https://www.youtube.com/watch?v=slxOrCXxXOg
08:06 PM rue_mohr: https://www.youtube.com/watch?v=5vLEtVLV71I
08:06 PM rue_mohr: https://www.youtube.com/watch?v=j4uz_yha9uI
08:06 PM rue_mohr: https://www.youtube.com/watch?v=qZF9WJ1Ueew
08:06 PM rue_mohr: all the things that robots do is mondane,
08:07 PM rue_mohr: but if you analize it too much, you will realize that EVERYTHING is mondane
08:10 PM rue_mohr: I wonder if I should delte all videos that have not had more than 100 hits in a year
08:20 PM Tom_L: that would be all of mine
08:23 PM rue_mohr: many of mine
08:25 PM Tom_L: just got my ethernet card working so i can run the mill software in the office for testing and run it in the shop on the old parport card
08:25 PM Tom_L: same card, different interface
08:27 PM Tom_L: holy crap... i got 2 that have 443 and 275 views
08:29 PM Tom_L: both on the old sherline
08:35 PM rue_mohr: :)
08:38 PM Tom_L: those $5 bobs you can get on ebay or ali work on this too
08:40 PM Tom_L: https://www.aliexpress.com/item/1pcs-MACH3-Engraving-machine-5-Axis-CNC-Breakout-Board-With-Optical-Coupler-For-Stepper-Motor-drive/32830611064.html?spm=2114.search0104.3.2.413558b5Fn3ZtN&ws_ab_test=searchweb0_0,searchweb201602_2_10152_10151_10065_10344_10068_10130_5722815_10324_10342_10547_10325_10343_10546_10340_5722915_10548_10341_10545_5722615_10696_10084_10083_10618_10307_5722715_5711215_10059_308_100031_10103_10624_10623_10622_5711315_5722515_
08:42 PM Tom_L: wtf is the USB cable for?
08:49 PM rue_mohr: the for grbl controller you use instead of the paralle port mach3 one
08:49 PM rue_mohr: :) or 5V power
08:50 PM Tom_L: i see
08:56 PM z64555: rue_mohr: what would you gain from taking down said videos?
11:47 PM rue_mohr: the same thing as mowing the lawn or shaving