#robotics Logs

Jul 12 2014

06:27 deshipu in retrospect, gluing them together wasn't the best idea
06:27 deshipu now it's difficult to replace
06:28 GargantuaSauce what kind of glue?
06:29 deshipu the choice of glue was actually accidentally quite good -- it's one of those two-part glues
06:29 deshipu but it's quite platic
06:29 deshipu plastic
06:29 deshipu and can be torn apart
06:30 deshipu so it's not as bad as it could be
06:30 deshipu still obnoxious
06:32 GargantuaSauce i swear by hot glue
06:32 GargantuaSauce generally strong enough but not TOO strong, similarly, and soluble in acetone
06:33 deshipu but it would be hard to get the servos aligned properly?
06:33 deshipu I mean, hot glue seems to be rather thick
06:34 GargantuaSauce you have a limited timeframe for alignment for sure, but it's pretty doable
06:34 GargantuaSauce and if it's wrong you can just yank them apart and start over
06:34 deshipu now my robot has one servo black: http://letsmakerobots.com/files/field_primary_image/IMG_20140712_123042.jpg
06:34 GargantuaSauce lol is that heatshrink on the mecanno beams
06:35 deshipu yeah
06:36 deshipu In retrospect, just heatshrink and icecream sticks would have been sufficient, without the screws
06:37 GargantuaSauce i am surprised you havent stripped the splines or the servo horns yet
06:37 GargantuaSauce i guess if they're nylon gear servos those would go first
06:37 deshipu the servos have metal gears
06:38 deshipu also, 2.5kg
06:38 deshipu of torque
06:39 deshipu I have 4 9kg*cm servos, and I'm considering using them for the middle joints
06:39 deshipu but I also want to show the robot at a conference in a week, so I don't want to make too many changes now
06:41 GargantuaSauce i burned one of my hexapod's servos about an hour before a demonstrationw
06:41 GargantuaSauce was not happy with that one
06:46 deshipu hexapods at least can somewhat limp with one leg not working
06:46 deshipu quadrupeds are much more vulnerable
06:47 deshipu I also just discovered something called Mech Warfare and I'm a little intrigued
06:47 deshipu I just can't understand why they are using bb guns and not laser tag
14:58 MrCurious GO NETHERLANDS!!!! Do what Germany did!
15:23 MrCurious 3 min in and NED scores... looking like a replay
15:38 MrCurious better start fueling up the water cannon trucks...
16:02 rue_shop3 stupid sports
16:04 MrCurious yeah
16:04 MrCurious but fun to watch
16:22 Tom_itx sooner watch grass grow
16:25 MrCurious no... thats called basketball or baseball
16:25 MrCurious its only once every 4 years
16:39 gushhtab Brasil ... tell me what it feels like!!
16:43 rue_mohr2 too hot to think
16:43 MrCurious they cant speak right now
16:44 rue_mohr2 24c right now in my room
16:44 robotustra_ drawing torso, 50% done
16:44 MrCurious a DIVE!
16:45 MrCurious get the AC
16:45 MrCurious or... make the AC
16:45 rue_mohr2 yea, I should make an AC
16:45 MrCurious fan + ice
16:45 rue_mohr2 water at, hmm -0.7 atmosphere?
16:46 rue_mohr2 er .7 atmosphere
16:46 rue_mohr2 whats this all relitive to again?
16:46 rue_mohr2 er .3
16:46 MrCurious make a fan blow through a mesh or matt that is fed by runoff from an ice bin
16:47 MrCurious of cource if done wrong, it might rain inside
16:47 shhtab in bed = feels like s
16:48 MrCurious seems they do not like HULK
17:17 robotustra_ http://www.youtube.com/watch?v=AEG362-Z1Mw
18:46 rue_house I have a smart caster wheel on a robot, its got an encoder to tell the computer how much its turned
18:46 rue_house it is one way data, transmitted from the caster only
18:46 rue_house it uses an ir link
18:47 rue_house so, I have to work out what protocol should come out of it
18:47 rue_house I'd like to just use mouse data, but its not one way
18:47 rue_house thoughts?
18:48 rue_house 8 bit grey code?
18:48 rue_house at a standard serial baud rate?
18:48 rue_house maybe I dont even need grey
18:48 rue_house hmm
18:54 GargantuaSauce how about just periodic updates over serial with a signed number of steps since the last update?
18:55 GargantuaSauce https://www.youtube.com/watch?v=g2xDFeCnaOY this is funny
19:14 MrCurious toys were not that cool when i was young.
19:14 MrCurious you wanted a factory or tower, you had to build your own damn factory or tower
19:32 GargantuaSauce i kind of want to do something like that but with toothpicks and gluegun
19:33 GargantuaSauce either a thing that climbs on the structure to build it from the bottom up, or sits at the base and builds it from the top down
19:33 m_itx feels serial updates over ir would be too slow for the code l
19:34 Hyratel GargantuaSauce, as an idea
19:34 MrCurious write up a plan. could probably get Dubai to fund it...
19:34 Hyratel have a feeder arm that holds a toothpick with one end aligned on the gluegun nozzle
19:35 MrCurious nah, use a air hose to feed the toothpicks up
19:35 MrCurious extend hose as needed
19:36 GargantuaSauce yeah that's sort of what i have in mind Hyratel
19:36 GargantuaSauce though if it's the mobile version, the manipulators will probably all double as grippers for locomotion
19:36 MrCurious use a glue that hardens when flashed with IR or UV?
19:37 MrCurious of cource you could just use wire, and solder...
19:38 MrCurious stronger, and quicker to fix a point and move on
19:39 Hyratel use copper clad steel wire if you're doing that
19:40 Hyratel s/a welding rod
19:40 GargantuaSauce easy to cut to arbitrary lengths too
19:40 Hyratel solders more easily than comparable thickness of solid copper because of lower heat dispersal
19:40 GargantuaSauce i guess plastic extrusion would be a decent option for this sort of thing too
19:40 MrCurious wonder if you could blow plastic bubbles to attach to the sides to skin and provide added ridgidity
19:41 MrCurious now if you could work out how to extrude plastic, with a wire filliment in te center of the extruded bits...
19:41 Hyratel plastic extrusion would be too heavy for itself
19:41 MrCurious like rebar in cement
19:42 Hyratel but using a combination
19:42 Hyratel s/a a wireframe builder that's followed by a plastic extruder
19:43 MrCurious suppose once the wire frame was up, and a pair of plastic skins... concrete could be pumped in to fill th voids...
19:43 MrCurious or even a expanding hardening foam like they use for insulation... spray it in to add more ridgidity without much weight
19:44 GargantuaSauce ooh i like that
19:44 MrCurious wire framed, plastic skinned, foam filled
19:44 m_itx wonders why rue_mohr2 has been so sparce here as of
19:45 MrCurious he was on last night
19:45 GargantuaSauce i got the impression his work is busy
19:45 MrCurious and i think this morning complaining about the heat
19:53 robotustra_ http://postimg.org/image/j02d7ls4r/full/
19:54 GargantuaSauce is that neck really three 2dof vertabrae
19:54 robotustra_ 3 DOF
19:54 GargantuaSauce lol
19:54 robotustra_ it's a balls in side
19:54 GargantuaSauce ok so what is going to actuate them
19:54 robotustra_ muscles
19:55 GargantuaSauce air muscles?
19:55 robotustra_ no
19:55 GargantuaSauce those silly thermal ones?
19:55 robotustra_ no
19:55 robotustra_ be patient
19:55 GargantuaSauce i refuse
19:56 GargantuaSauce tell me everything!
19:56 robotustra_ no :)
19:56 robotustra_ know how
19:58 robotustra_ I have some idea about new type of muscles but I didn't tested it yet
20:08 GargantuaSauce and this is where i would say "and you're not going to test it in isolation before designing the rest of the robot around it?" if i didn't do the same shit
20:11 robotustra_ GargantuaSauce: sure: I'll test it in secret underground lab, where I do all my investigations.. HA-HA-HA
20:12 GargantuaSauce you'll have to give me a tour sometime :)
20:13 robotustra_ :)
20:13 robotustra_ I wish I had one
20:15 GargantuaSauce me too
20:18 GargantuaSauce i left my hexapod in the sun and all of the rubber bands fell apart :(
20:18 GargantuaSauce also i cant remember its ip address
20:22 robotustra_ :)
20:23 robotustra_ use latex not rubber
20:25 GargantuaSauce they're from a bag of rubber bands from the dollar store...i didnt expect much
20:36 robotustra_ GargantuaSauce: for $2-3 you can buy on ebay excellent latex tubes
20:36 robotustra_ more durable than dollar shit