#robotics Logs

Feb 18 2014

08:40 rue_house power outage gotta go
08:46 armyofevilrobot1 @rue_house; big one, got me too.
09:30 robotustra pity to hear
09:30 robotustra USSR never had problems with outages
09:30 robotustra because the system war prepared to nuclear attack
09:30 robotustra was
09:31 robotustra and all wires were hidden under the ground
09:32 robotustra only in canada and us all wiring are in the wooden posts
09:32 robotustra I fill here like in a village
09:33 robotustra US is not even have a centralized power grid
09:33 robotustra shame on it
09:35 robotustra There are 3 types of countries
09:36 robotustra Developing, developed and retarded
09:36 robotustra so I came from developed to developing country
09:38 Hukka We have mostly underground lines because the trees fall on them in storms, not just in nuclear attacks...
09:47 fulcan what would be a good way to ground out altcoin mining rigs (a raw motherboard with a buttload of video cards)? because of all the pcie cards, a chassis is unrealistic. What an efficient/decent way to solve this in an apartment setting?
09:51 robotustra Hukka: In Canada there are also a lot of outages because of tree fall, but nodoby cares
09:52 robotustra because of wind/ice
09:52 robotustra because this is a country of "service" type of economics - if nothing to repare - no profit
10:00 robotustra Hukka are you from finland?
10:01 Hukka Yeah
10:02 robotustra are you extrovert or intravert?
10:02 robotustra introvert*
10:05 robotustra or you don't know what does it mean?
10:07 robotustra Finish introvert looks at his own boots during conversation while finnish extravert looks to the boots of opponent.
10:15 StrangeloveMD_ I am thinking it would be possible to loop what is effectively a bimetallic wire into a heat-differential sphincter. Does anybody know of such a thing?
10:16 GargantuaSauce sounds kinky
10:16 StrangeloveMD_ nickname doesn't help I guess. Damn you Kubrick!
10:17 GargantuaSauce i dont think bimetallic structures work the way you think they do
10:17 GargantuaSauce they don't contract, they bend
10:17 GargantuaSauce and it's pretty subtle
10:18 GargantuaSauce even a mercury switch requires a big spiral of like 8 turns of a bimetal strip to be tilted a few tens of degrees over a range of 25C or so
10:19 StrangeloveMD_ Both metals expand/contract at different rates with thermal cycling and the difference is exhibited in preferential digression iirc
10:19 GargantuaSauce yeah i don't see how that could be used to produce a sphincter kinda thing
10:19 GargantuaSauce maybe muscle wire, which is just a nichrome alloy or something that contracts when you heat it up
10:19 StrangeloveMD_ Hmm. Not sure how it couldn't really.
10:20 StrangeloveMD_ Orifice size may be microscopic
10:20 GargantuaSauce and presumably you want it to contract with a reasonable amount of force right
10:20 GargantuaSauce hmm
10:20 robotustra to bend bimetal you need to apply quite big current
10:20 GargantuaSauce MEMS is pretty magic, cant help you there
10:20 StrangeloveMD_ application specs are uncertain, but sealing against a few kpa would be nice indeed.
10:22 GargantuaSauce what are you building stark?
10:22 StrangeloveMD_ robotustra: I was hoping to take advantage of thermal expansion. Reading various MEMS pdfs now
10:23 robotustra what is MEMS?
10:23 StrangeloveMD_ Microelectromechanical systems
10:23 Hukka Category of sensors
10:23 GargantuaSauce not just sensors, mechanisms in general
10:23 GargantuaSauce stupidly small ones
10:23 StrangeloveMD_ tiny lil guys
10:23 Hukka Oh, haven't seen other than sensor stuff
10:23 Hukka I guess it's just my country
10:24 GargantuaSauce their use is only prevalent for stuff like that, but there are other applications being developed
10:24 StrangeloveMD_ Thing robots that scape arteries. MEMS development involves the best kinds of crazy people.
10:24 StrangeloveMD_ think* scrape*
10:24 robotustra give me a PDF example with MEMS
10:24 StrangeloveMD_ Time for a new keyboard.
10:25 StrangeloveMD_ google search: "MEMS Filetype:pdf"
10:25 GargantuaSauce the chip in a DLP projector is a good example
10:25 StrangeloveMD_ Then you'll learn application specific search terms
10:25 robotustra ok
10:25 robotustra I usually do my own mems
10:26 GargantuaSauce no you don't
10:26 robotustra :)
10:26 StrangeloveMD_ hehe
10:26 rangeloveMD_ wants robo's micros
10:26 StrangeloveMD_ it's much better than mine.
10:27 StrangeloveMD_ Also, in the course of my research "ABSTRACT This paper presents an approach for the thermal control of an artificial anal sphincter using shape memory alloys." Well that's only sort of what I'm after....
10:27 GargantuaSauce http://img3.joyreactor.com/pics/comment/water-drop-et-cool-922853.jpeg
10:28 StrangeloveMD_ CuAlBe alloy. very interesting....
10:28 robotustra Be is toxic
10:28 robotustra forget
10:28 StrangeloveMD_ Oh internet, I love you. Something makes me thing no longer visiting reddit takes me out of the global loop
10:29 StrangeloveMD_ Toxic in that it makes you forget?
10:29 StrangeloveMD_ Interesting stuff, in and of itself, this alloy
10:29 robotustra I suggest you to forget to work with toxic materials like Be
10:30 GargantuaSauce it's only a problem if you inhale it as dust or vapour
10:30 StrangeloveMD_ But if we all did that the Be industry would collapse. Then where would we be? It plays a hidden role in an startling amount of modern tech
10:30 StrangeloveMD_ Mystery of the Wandering Guest is solved.
10:45 robotustra yeah, dont heat it and sniff
10:46 robotustra but he wanted to use this material as bimetal I think
10:46 robotustra and bimetal supposed to be heated
10:47 robotustra this material is videly used for car gear boxes
10:47 robotustra widely
10:51 StrangeloveMD_ the CuAlBe is a shape memory alloy. I was merely pointing out it's existence, as I wasn't aware of it specifically.
10:51 StrangeloveMD_ It would, however, work a treat.
10:54 StrangeloveMD_ Whether bimetallic devices are "supposed to be heated" is debatable. The ones in thermostats don't get incur heat above ambient.
10:55 robotustra yeah, range is matter
11:03 GargantuaSauce off to cuba for a week! woo
11:06 StrangeloveMD_ awesome
11:06 StrangeloveMD_ Never even been that far south myself.
11:20 GuShH_ GargantuaSauce: bring me some cigars?
11:20 GuShH_ shoot castro, have sex with a bunch of locals and bring home some of castro's gold while you're at it
11:21 GuShH_ INSIDE one of the locals, which you shall bring back home as well.
11:21 GuShH_ then ebay her/him/it
11:21 GuShH_ you'll love the cars over there... it's a blast from the past.
12:08 MrCurious if we normalize relations with cuba, america would see a bump in the number of new circa 60's movies being made
12:09 MrCurious of cource ars from back then were user serviable. good luck keeping todays cars running for decades in isolation from teh founding technology sources
12:18 GuShH_ MrCurious: everything used to be user servicable
12:18 MrCurious eye
12:18 GuShH_ including, at one point, condoms
12:18 ShH_ shi
12:19 MrCurious that would mean that this phrase has already been uttered... "you going to just throw that away? yes, it has a hole. can i have it? i can mend it and get some use out of it."
12:19 armyofevilrobot1 rule34 for repair?
12:19 MrCurious i guess being best friends went much deeper in the middle ages...
12:24 GuShH_ MrCurious: eek
12:24 GuShH_ armyofevilrobot1: diapers were also reusable...
12:25 MrCurious i guess it was a different time, and you had to be there to understand
12:25 GuShH_ I can only imagine the smells.
12:25 GuShH_ sweat and piss and...
12:25 GuShH_ well horse poop, chicken shit and human shit, among others.
12:26 MrCurious does that mean barn yard animals were .... *GASP* ... reusable?
12:26 ShH_ sh
12:26 MrCurious damnit. i knew there was a line, and still i crossed it... what is wrong with me
12:27 MrCurious why cant i respect the chalk line
12:27 GuShH_ we used to have a teacher... she was into chalk.
12:27 GuShH_ that is, she would EAT the chalk.
12:28 GuShH_ http://en.wikipedia.org/wiki/Pica_(disorder)
12:29 GuShH_ http://reprap.org/mediawiki/images/2/2d/Edm_schematic.png
12:29 GuShH_ must. try. this.
12:30 ShH_ guesses his hair loss had nothing to do with his caffeine in
12:30 GuShH_ although 2 weeks isn't long enough to call it I guess
12:30 GuShH_ I did quit drinking coffee and it's been 2 weeks.
12:30 GuShH_ cold turkey too.
12:36 myofevilrobots looks around... cautiou
13:11 MrCurious baldness is a sign of inteligence. brain heat kills hair, yeah, thats my story and am sticking with it
13:14 GuShH_ MrCurious: you could argue baldness is part of human evolution
13:14 GuShH_ because we should be naturally getting rid of hair.
13:14 GuShH_ sadly that's not how it's seen :p
13:18 adam789654123 Or how about you go bald on your head and get hairy everywhere else! :O
13:18 MrCurious thats how it works.
13:18 adam789654123 yikes!
13:18 MrCurious there will be suprises in your ears, nose, and eyeborws
13:18 george_ hello, i want to build a self balanced robot, any projects?
13:18 MrCurious did you google it
13:18 GuShH_ george_: no.
13:19 MrCurious can we google it for you? :P
13:19 george_ any recommended project?
13:19 MrCurious 1: google "self balancing robot"
13:20 MrCurious 2: read
13:20 MrCurious 3: think
13:20 adam789654123 Ever find a hair on your arm or something thats like two feet long, and you wonder, when did this happen?
13:20 MrCurious 4: do
13:20 MrCurious once you have started doing, that is the time to come here to discuss
13:20 george_ do you really spent your time saying thinks like that?
13:21 MrCurious did you google self balancing robot yet?
13:21 george_ yup, and some control books of that
13:21 MrCurious good, go on, where is your issue
13:21 adam789654123 george_: yeah. im thinking the same. What are your thoughts on the subject?
13:22 adam789654123 george_: yeah. what do you think would be a good/interesting/useful, or whatever project?
13:22 MrCurious i am sure you have visited letsmakerobots to see what others have done to build them
13:22 MrCurious as they document their steps and code....
13:22 MrCurious "george_: hello, i want to build a self balanced robot, any projects?"
13:23 MrCurious i believe the guy wants a self balancing bot
13:23 george_ IMU, H-bridge, Torque of the motor, open or closed control of the position
13:23 MrCurious got a prototype?
13:24 MrCurious would also look into PID
13:24 MrCurious as the imu will tell you where you want to be, and PID will help with getting you to that without overshooting
13:24 george_ MrCurious, wrong assumption, will look on that page.
13:25 george_ I am interest in the parts/model/where to buy.
13:25 MrCurious oh
13:25 MrCurious like a self balancing toy
13:25 george_ you don't prototype before seeing other projects...
13:25 MrCurious that says we are back at step 1
13:26 MrCurious i thought we were at 3
13:26 george_ not exactly a toy, it is for a project...
13:27 MrCurious so specifically, what can we do for you?
13:27 george_ adam789654123, do you know any recommended project about self balancing robot?
13:28 adam789654123 no. im basically the last person you should ask about robotics in this chat ;)
13:28 MrCurious like this?
13:28 MrCurious http://www.instructables.com/id/Self-Balancing-Segway-Instructabot/
13:28 adam789654123 just think its an awsome subject, so im here
13:29 MrCurious sorry for being gruff. people failing to google before engaging mass people upsets me
13:29 MrCurious its a personality flaw :)
13:29 MrCurious i am working on it
13:30 george_ MrCurious, i have looked some of those. Should i go for closed loop control on the wheels or open control like the one you posted?
13:30 MrCurious i would say both
13:30 MrCurious build with closed loop, and ignore it down the road if you want
13:30 MrCurious its about the learning
13:31 MrCurious and doign is a big part of the learning
13:31 MrCurious i went the omni wheel route
13:31 MrCurious dont think of it as much of building a final polished product
13:31 MrCurious think of bilding a training and experimentation platform
13:32 MrCurious that you can try different things with
13:32 george_ i don't have the encoders on the wheels... and my accelerometers don't have the gyros.
13:32 MrCurious you might even use a system to shift a mass on a inverted pendulum to balance it.
13:32 MrCurious ahh! specific questions
13:33 MrCurious http://www.ebay.com/itm/10DOF-IMU-MPU6050-HMC5883L-BMP085-Flight-Control-Gyroscope-Acceleration-Compass-/360805656195?pt=LH_DefaultDomain_0&hash=item5401b16683
13:33 MrCurious got $12 you can spare?
13:33 MrCurious and for wheel encoders something from this site http://www.pololu.com/product/1217
13:33 MrCurious or its cheeper ebay equiv...
13:34 george_ MrCurious, without the gyros my robot will integrate de error and will fall.
13:34 george_ with time...
13:34 MrCurious the ebay link comes with a 3 axis gyro, 3 axis accelerometer, and 3 axis magnetometer
13:34 MrCurious $10 to solve the gyro problem
13:35 MrCurious it is i2c and easy to talk to on arduino avr
13:37 george_ i2c is better than analog?
13:39 MrCurious imho, its digital
13:40 george_ those encoders are really expensive
13:49 MrCurious hencce the ebay comment
13:50 MrCurious work is exploding have to pay attention there...
13:51 george_ does that encoder comes with the wheel?
13:51 george_ the wheel with the holes i meant
13:52 MrCurious no all seperate
13:52 MrCurious and yes they are expensive
14:02 george_ MrCurious, do you think the pololus enconder will work with this set of encoder wheels: http://www.aliexpress.com/item/New-Arrival-Motor-Smart-Robot-Car-Chassis-Tracing-car-boxKit-Speed-Encoder-Send-the-Battery-Box/1337327225.html
14:02 MrCurious no
14:03 MrCurious really, you want the encoder on the motor side of the gears
14:03 MrCurious so you can get much more precise positioning, not on the output side of the gear where you get very cource grained positioning
14:07 MrCurious something lilke this http://www.pololu.com/product/1445
14:07 MrCurious but $$$
14:08 george_ you mean that you want the encoder before the gear box?
14:08 george_ this is how it would look assembled: http://www.ebay.com/itm/Smart-Robot-Car-with-Plastic-Tire-Wheel-1-48-1-120-DC-Gear-Motor-Encoder-Disc-/231130151482?pt=Apparel_Merchandise&var=&hash=item35d06e3a3a&vxp=mtr
14:09 MrCurious yes
14:10 MrCurious so 1 turn of motor registers a few pulses but turns into 0..01 turn of wheel
14:10 MrCurious that encoder is AFTer the gears
14:10 george_ get it
20:37 rue_house I suppose I have to be carefull, if I leave too many peanuts on the shop roof, it could attract elephants, which would cause damage to the shop roof
20:49 zap0 your logic is flawless
20:53 sherlock zap0: but not for the reasons you think
20:53 sherlock peanuts attract mice, which elephants are scared of
20:53 sherlock BUT elephants want to show they are manly
20:53 sherlock and go to the only place with the most peanuts they can think of, rue_house's shop
20:53 zap0 even the female elephants?
20:54 zap0 manly is not getting into mousy situations.
20:54 sherlock zap0: the patriarchy puts pressure on them
21:05 MrCurious my computer smells like soft cat food
21:06 MrCurious a cat decided the laptop keyboard was the best place to mull over a chunk of it
21:23 rue_house be glad there are no hairballs
21:24 robotustra_ Z-z-z
21:28 MrCurious hairballs smell better than soft catfood
22:09 rue_house if you needed to make a system that could physically locate an electrical impulse in a bowl of jelly, without passing the surface of the jelly, how would you do it
22:10 rue_house I'm thinking flight time
22:11 MrCurious like the bullet sourcec tracking system
22:11 MrCurious triangulation and time offsets
22:11 rue_house yea
22:11 MrCurious question is how consistent is flight time through jello
22:12 rue_house that IS a good question, esp if its not consistant jello
22:12 MrCurious jello cubes in pudding
22:12 MrCurious or... rice puddinng or tapioca
22:12 rue_house no, jello with a cerebral cortex on one side
22:12 rue_house er, I mean with bubbles
22:12 MrCurious you feed your brain jellow?
22:13 MrCurious is that safe?
22:13 rue_house brain? who said brain? not me?
22:13 rue_house jello with bubbles
22:14 MrCurious jello with bubbles of a variety of gasses...
22:15 rue_house now, what if there were two impulse sources going off randomly at once, I wonder how you could sort out whats what
22:15 MrCurious if you want to make it even harder... stelwool encased in jellow
22:17 rue_house or put a tinfoil hat on it
22:24 MrCurious No Swiss fighter jets were scrambled Monday when an Ethiopian Airlines co-pilot hijacked his own plane and forced it to land in Geneva, because it happened outside business hours, the Swiss Air Force said.
22:24 MrCurious BAHAHAHAHAHA
22:25 MrCurious we are closed, please come back tomorrow
22:37 robotustra_ hm... interesting
22:38 MrCurious hello robotustra
23:19 rue_shop2 armyofevilrobots, did you get this mornings power failure?
23:59 MrCurious i miss power failures