#robotics Logs
Feb 17 2018
#robotics Calendar
12:16 AM rue_: the number of variations of 3d printer parts is getting insane
12:19 AM rue_: https://www.thingiverse.com/thing:7787
12:19 AM rue_: but everyting you can look for turns up
01:05 AM Jak_o_Shadows: I want to swap out my vertical x-carraige for a horizontal one at some poit
01:09 AM mrdata is now known as mrdata_briefly_t
01:09 AM mrdata_briefly_t is now known as mrdata
01:23 AM rue_: ?
01:23 AM rue_: the verticle hugs the z rails better?
01:23 AM Jak_o_Shadows: I just don't like how the extruder cantilevers off it
01:24 AM rue_: http://ruemohr.org/~ircjunk/projects/reprap2/p1080565.jpg
01:24 AM rue_: I put mine on a heavy block
01:24 AM rue_: but I did it bowden
01:24 AM rue_: which I think I regret
01:25 AM mrdata: thats a huge looking bed
01:25 AM mrdata: do you get warping?
01:25 AM rue_: I upsized it a little,
01:25 AM Jak_o_Shadows: Mine cantilevers off two teensy bolts
01:25 AM Jak_o_Shadows: stupidest thing in existance
01:25 AM rue_: normally you take the 3' store legths of 5/16 rod and cut them into stupid little peices and have little bits of waste
01:26 AM rue_: so I resized it to just cut the rods in half
01:26 AM rue_: its only 6-7cm larger, but dosn't waste lots of threaded rod
01:26 AM Jak_o_Shadows: I did fixed y-ends. Less waste, less cutting. Wish I had a drill press, would've made it easier
01:27 AM rue_: on that one I also reduce-drove everything
01:27 AM rue_: which is AWESOME
01:27 AM rue_: http://ruemohr.org/~ircjunk/projects/reprap2/p1080516.jpg
01:27 AM rue_: http://ruemohr.org/~ircjunk/projects/reprap2/p1080518.jpg
01:27 AM rue_: I also seperated the X frame distance structure from the belt tensioner
01:28 AM rue_: that end of the square rod floats in that holder
01:28 AM rue_: http://ruemohr.org/~ircjunk/projects/reprap2/p1080526.jpg
01:29 AM rue_: I also use compression rings on the shaft attachments, works much better than the tension based ones
01:29 AM rue_: http://ruemohr.org/~ircjunk/projects/reprap2/p1080527.jpg 2:1 geared
01:29 AM rue_: I made a geartbox that presents as a nema17
01:30 AM rue_: so i can take anything meant for a nema17 and insert a 2:1
01:30 AM rue_: http://ruemohr.org/~ircjunk/projects/reprap2/p1070722.jpg
01:31 AM rue_: I use a 3 screw system, screw trying to manage 4 screws and warping
01:31 AM rue_: springs hold down against screws
01:32 AM rue_: I didn't take a good photo of that block that holds that head
01:40 AM rue_: I might build a printer with a belt driven Z, use the geared steppers I have
01:47 AM theBear: 3 legs/mounts/whatevers always makes more sense than 4, cos you need infinitely perfect adjustment/matching with 4, while 3 just works, and if yer dealing with something involving a hinged plane, like a door, 2 hinges wins over >=3 for kinda the opposite reason, any more than one each end and they gonna fight unless the pivot/hinged-edge is infinitely straight... that's what i know about screw warp 4 keptin (nuclear wessels <grin>)
06:02 AM BitEvil is now known as SpeedEvil
06:37 PM codepython777: https://www.alibaba.com/product-detail/NIUWHEEL-HORIZON-ELECTRIC-MOTORCYCLE-72V-3000w_60726633111.html - is this real? not a scam? looks too cheap to be true
06:38 PM ace4016: it's clearly like those shriner bikes
06:39 PM SpeedEvil: It's probably not a scam as such.
06:39 PM SpeedEvil: But a _lot_ of prices on alibaba are sort of only to get you to talk to them.
06:41 PM theBear: hmm.... i'm running outta these little $2 shop ratchet straps... i guess i better find a few bolts and stick em in this chair before it's too late ! (NIGHTMARE situation ! jeez it's hard being theBear some months...)\
06:42 PM SpeedEvil: :)
06:42 PM theBear: it's kinda entertaining they even bothered to make the things... the metal is as soft as some drink cans, way softer than any soup/preserve tin ;-)
07:59 PM * rue_shop3 straps theBear to the chair, "like that?"
08:00 PM theBear: so far so good :-] but you just watch... sooner than later, there'll be a tearey noise, or a loud clunk and suddenly half the chair and half of me be looking like we were falling over but time was frozen when we was only halfway to the floor
08:11 PM rue_shop3: food, I need to go shopping too
08:12 PM rue_shop3: ugh I hate driving
09:20 PM codepython777: SpeedEvil: does anyone sell electric bikes at that price point in the western world?
09:22 PM rue_: theBear,
09:23 PM rue_: one of those 8-| moments
09:23 PM rue_: I opened the dryer door and noticed something stuck in the door
09:23 PM rue_: actually stuck between the drum and the inner doorframe
09:23 PM rue_: so I pulled on it and it didn't move
09:23 PM rue_: so I stared closer at it, and it was a black wire
09:24 PM rue_: looped out from under the drum/doorframe and back
09:24 PM rue_: and then I noticed that it was bare in one spot
09:24 PM rue_: and then I noticed it was worse than that, the ends were twisted and broken
09:25 PM rue_: but then i had a thought
09:25 PM rue_: I pulled on it harder and it came out, it'd just been a piece of wire drop out of a pair of pants in my laundry and get stuck there
09:25 PM rue_: FEW!
09:26 PM Tom_L: not sure i wanna know why you got wire in your pants
09:28 PM rue_: electrician remember?
09:29 PM Tom_L: phew
09:30 PM Tom_L: so when you make handles how do you do the slot?
09:31 PM rue_: 3d printed
09:31 PM rue_: is your memory ok?
09:31 PM rue_: ...
09:31 PM Tom_L: naw not usually
09:32 PM Tom_L: i thought you said you offered a metal one
09:32 PM rue_: dont go gettin alztimers, or every day will be a wonderfull new experience
09:32 PM rue_: trigger
09:32 PM rue_: handle and "front head assembly" are printed
09:33 PM rue_: A2 and A7 are printed
09:34 PM rue_: the other guy who used to make them split the peices and pinned them togethor
09:34 PM Tom_L: yeah
09:34 PM rue_: aka, make it as a solid block, cut it twice, lose part of the middle slice and pin the remains back togethor
09:35 PM Tom_L: or make 2 halves and 3-4 screws
09:36 PM Tom_L: like a box knife
09:36 PM rue_: had to be plastic, tho, metal would be too heavy
09:37 PM AchiestDragon: 2 days , servos changed , ffs around 300 m3 nuts bolts with at least 100 of them locking nuts ,,, but finaly have servos working , and also it can stand on 3 legs under its own power without metling them , next task actualy get the servo software sorted so it dirves them i nthe right direction
09:37 PM rue_: sure the origional was 15mm plywood (1/2")
09:38 PM rue_: -scale
09:38 PM rue_: AchiestDragon, scale, and offset
09:38 PM rue_: and I have to add range limits
09:40 PM AchiestDragon: no my pwm is linked to the analog position read forming a pll loop in software ,
09:40 PM rue_: adc values -> robot angles
09:40 PM rue_: thats a scale and an offset
09:40 PM AchiestDragon: there are range limits in the software also
09:41 PM rue_: yea, my servo library dosn't impose limits
09:41 PM rue_: its unlimited
09:41 PM rue_: ... selling feature?
09:42 PM rue_: I need a limited version tho
09:42 PM AchiestDragon: i need to get tehe adc values scaled to =the needed pwm values
09:42 PM rue_: scale and offset
09:42 PM AchiestDragon: tehe/the
09:43 PM rue_: scale and offset 'click' scale and offset 'click'scale and offset 'click' scale and offset 'click' scale and offset 'click' scale and offset 'click'
09:44 PM * z64555 tosses a flip and switch in there
09:44 PM AchiestDragon: yea there calibration values in the software
09:45 PM AchiestDragon: already done that bit , but not calibrated yet as the servos where not working properly
09:46 PM rue_: ok they close at 10pm
09:46 PM rue_: so, your working on that now?
09:46 PM rue_: I can race you?
09:49 PM AchiestDragon: i also reprinted shortended lower leg sections shoter by 40mm so the feet dont touch the ground when its curled up in storage/home position
09:51 PM AchiestDragon: even so there still 260 mm long
09:53 PM AchiestDragon: i will be working on it for the next few months by the looks
09:54 PM AchiestDragon: trying to get the pi code sorted so i can get positional diagnostics on actual pwm positions and adc values to check how close they are matching
09:55 PM AchiestDragon: and that its sending them in the right directions when trying to pll lock them
09:56 PM AchiestDragon: its also got backlash compensation
09:57 PM AchiestDragon: the servos have about 1.5degree backlash
11:55 PM rue_: ouch
11:55 PM rue_: passive compliance :)
11:58 PM rue_: picked up junk from hospital
11:58 PM rue_: looks like most of this lot will go to ewaste