#robotics Logs

Dec 25 2013

10:34 sherlock fwwffwwB-)
10:34 sherlock lptptltret
10:34 sherlock l
11:10 GargantuaSauce i agree
12:37 MrCurious what a lovely day out!
12:38 MrCurious 24C and a light breeze
12:38 MrCurious at 0am
12:38 MrCurious 10
13:23 robotustra -18 outside
13:23 robotustra but there is a sun
13:23 robotustra http://cs424530.vk.me/v424530121/59df/U-7_22pRCNM.jpg
13:41 MrCurious GargantuaSauce: what was that delta possitioner that thrust-vectored a rocket/plasma engine
15:00 MrCurious anyone know the math to combine a 9dof sensor to get accurate orientation and motion?
15:48 MrCurious http://gentlenav.googlecode.com/files/DCMDraft2.pdf
15:48 MrCurious next wish, a simple reference implementation :)
16:11 ShH_Lap pokes MrCur
16:11 ShH_Lap pokes MrCurious again for good mea
17:21 GuShH_Lap hmmmm
17:21 GuShH_Lap so third worldy of this country, lost power
17:21 GuShH_Lap it was possibly the transformer I believe
17:22 GuShH_Lap by what I heard...
17:22 GuShH_Lap running off backup :/
17:53 rue_shop3 yay, the new parting tool seems to work great
19:07 Curious pokes GuShH
19:22 GuShH_Lap MrCurious: what
19:22 GuShH_Lap we had another brownout, this time in my zone... 3 hours out!
19:22 GuShH_Lap I should probably get investing in converting the house to take the genset...
19:23 GuShH_Lap and some emergency lights while I'm at it, of course their price went up now because the demand went up, because it's the country of all things inverse.
20:05 MrCurious out go the lights.... in argentina
22:10 GargantuaSauce MrCurious: canfield joint
22:11 MrCurious ty
22:11 GargantuaSauce http://www.cae.tntech.edu/~scanfield/Summary%20information%20on%20Canfield%20Joint/
22:12 GargantuaSauce http://scholar.lib.vt.edu/theses/available/etd-24129959711591/
22:14 MrCurious was thinking that would be good for robotustra's robot neck
22:14 GargantuaSauce it can't pivot
22:14 robotustra тще пщщв
22:14 robotustra not good
22:14 GargantuaSauce it can only tilt
22:14 robotustra even for satelite
22:14 MrCurious hmmm
22:15 robotustra if it's brake - satelite will never finish menuver
22:15 GargantuaSauce it's less complex than traditional orthogonal rcs
22:15 GargantuaSauce nasa has adopted it for their new manned design
22:16 robotustra bad for tham
22:16 robotustra they will have problems with fuel pipe
22:17 robotustra it will fail if they will use it too often
22:17 GargantuaSauce these are claims that would be easily proved false with 10 minutes of research on the subject
22:18 GargantuaSauce http://www.cae.tntech.edu/~scanfield/Summary%20information%20on%20Canfield%20Joint/WristRev4_4.jpg
22:18 robotustra experiment could not PROVE anything
22:19 robotustra it can just DISPROOVE
22:19 GargantuaSauce well i am going to need you to prove that you know this shit better than nasa
22:19 robotustra I know 1 thing
22:19 robotustra no
22:19 robotustra 2 things
22:20 robotustra 1) non moving parts wearing less
22:20 robotustra 2) more complex things are breaking more often than simple ones
22:20 robotustra just because of probaility laws
22:20 GargantuaSauce with traditional rcs you have four times as many thrusters
22:21 robotustra count how many parts has this joint
22:21 robotustra and any break of any piece lead to failure
22:21 GargantuaSauce and how many does a thruster have?
22:22 GargantuaSauce we're talking pumps, valves, pressure regulators
22:22 robotustra thruster is a dummy code
22:22 robotustra cone
22:22 GargantuaSauce yeah. no.
22:22 GargantuaSauce complex hydrodynamic+electromechanical system
22:22 Triffid_Hunter reliability numbers always amuse me.. at 99.999% reliable manufacture, the average modern car has 5 broken pieces
22:22 robotustra all this new stuff also have pumps, etc
22:23 GargantuaSauce yes, a quarter as many
22:23 robotustra plus many many moving parts
22:24 robotustra and there is one more stupid disadvatage - is the speed of work
22:24 robotustra 4 thrusters will work way faster than this one
22:24 robotustra because of repositioning
22:25 robotustra and if it stuck in some strange position og one lever is bent - ta-da--- the satelite will flu away
22:25 robotustra fly
22:26 robotustra I know that modern enggineers just waste peoples money
22:26 ace4016 s/engineers/management
22:26 robotustra yes
22:27 robotustra they just want to put more and more in such simple stuff
22:27 robotustra they try to complicate things and they are getting less and less relyable
22:27 GargantuaSauce lol
22:27 robotustra but nobody cares
22:27 ace4016 if engineers had their way, it wouldn't be like that
22:28 robotustra of cause
22:28 ace4016 management and business execs have more play into what goes on
22:28 GargantuaSauce that is patently false anyway
22:28 ace4016 if you can't offer a new feature, you're no good!
22:28 GargantuaSauce when it comes to spaceflight
22:28 ace4016 spaceflight is a bit different
22:28 robotustra this 2D morion could be done with TWO motors
22:28 robotustra why they put 3 motors there?
22:28 ace4016 although, i can assure you, management is the problem as well....
22:29 ace4016 NASA is riddled with terrible management, and the way the USG handles contracts and such leads to less than par products; or at least an absorbant amount of money spent
22:29 robotustra this mechanism - is a good way to scrap satellite
22:30 ace4016 (coming from someone that works with this stuff...)
22:30 robotustra NASA is not the CAKE any more
22:30 robotustra and SPACEX proved it
22:30 GargantuaSauce spacex is still 40 years behind
22:30 ace4016 spacex is a very new thing
22:30 robotustra they did a rocket in short term
22:31 ace4016 also, they have most of the same issues NASA did
22:31 robotustra 40 years behind of what?
22:31 GargantuaSauce progress
22:31 ace4016 if you think otherwise, their stockholders love you for thinking that way :P
22:31 robotustra HOW DARE YOU TO CALL THIS PROGRESS????
22:31 robotustra it's bullshit
22:32 robotustra not a progress
22:32 ace4016 most of the accomplishments are either not real accomplishments, or they're overstated too...
22:32 robotustra they burned billions of dollars because of polititian sick ambitions?
22:33 robotustra burned people alive
22:33 robotustra inside rockets
22:33 robotustra in oxigen atmosphere
22:33 robotustra idiots
22:34 robotustra APOLLO program was a waste of money
22:34 ace4016 ?
22:34 robotustra they could do much more and with less money
22:34 robotustra if they didnt rush after USSR
22:34 ace4016 ah
22:35 ace4016 you must not know how government acquisition works :P
22:35 robotustra I don't care
22:35 ace4016 there's also a bit of another side to it
22:35 robotustra NASA is just yet another masson's enterprise
22:35 robotustra they don't care about simple people
22:36 robotustra like any other US government institution
22:37 ace4016 there was little use for getting into space in the grand scheme of things at the time (started to change and progress as time went on of course); a private company could have probably spent less and achieved much more, except they wouldn't have taken the chance and put the money into it to start with
22:38 ace4016 the only applications for it at the time was military
22:38 GargantuaSauce nasa brought men to the surface of the moon and back 12 years after the first manmade object was put into low earth orbit
22:38 robotustra don't want to talk about this shit any more
22:38 robotustra they don't deserve my attention
22:38 GargantuaSauce i consider that a pretty significant feat
22:38 ace4016 if you weren't a defense contractor, there was no interest in space apart from the cool sci-fi stuff
22:38 ace4016 but that doesn't make you money
22:39 robotustra commerse is killing science
22:39 ace4016 it has always been this way
22:39 robotustra us people do money, not science
22:40 ace4016 it isn't a new concept or event
22:40 robotustra why nasa put human to the moon? becaus it was cheaper than to build a robot and send it there
22:40 GargantuaSauce robots weren't even a thing yet
22:41 robotustra ORLY&
22:41 robotustra ?
22:41 ace4016 and computers were obnoxiously big
22:41 robotustra russian did it in 1973
22:42 robotustra america kills people
22:42 robotustra it does'n care about human lifes
22:42 robotustra lives
22:42 ace4016 lol...
22:43 robotustra all wars is a proove
22:43 robotustra proof
22:43 ace4016 yes, because this isn't a product of humans in general; only the US :P
22:44 ace4016 no cosmonaut ever lost his/her life
22:44 robotustra it was much easier to send 3 men to the moon than 1 robot
22:44 robotustra and this was done sucsessfuly
22:45 robotustra ace4016: chalenger?
22:45 ace4016 the space race wasn't about technological progress
22:45 robotustra a number of apollo
22:45 ace4016 it was about apparent superiority
22:45 robotustra what was superiority?
22:46 ace4016 also, a lot of what i said was sarcasm :P
22:46 robotustra ok
22:46 ace4016 what could a robot do in space?
22:47 ace4016 to people back in the 50s-70s, not much
22:47 ace4016 getting people was a more impressive feat if you could keep the humans alive in the harsh conditions of SPACE!
22:48 ace4016 otherwise you just sent a piece of machinery somewhere
22:49 ace4016 that's essentially what people thought of the soviet robot; it was an R/C car that couldn't be nearly as awesome as man
22:50 ace4016 even now, after multiple rovers have been sent to mars, people still can't wait for the first manned mission to mars
23:03 robotustra t will never happen
23:04 robotustra they will die of cosmic irradiation
23:04 robotustra in their way to mars
23:04 robotustra on
23:04 robotustra didn't you know about it?
23:05 GargantuaSauce yes obviously we will never come up with a shielding solution
23:05 robotustra they will get juge amount of radiation before they get to the mars
23:05 robotustra do you know what should be the shueld from cosmic rays?
23:06 robotustra if should be compartible with the field of EARTH
23:06 GargantuaSauce no, how about you bestow your expert opinion upon me
23:07 robotustra ok
23:07 robotustra do you know what is solar wind?
23:07 GargantuaSauce yes
23:07 robotustra it consists of ... continue
23:08 GargantuaSauce protons and the occasional alpha particle
23:08 robotustra at what speed?
23:08 GargantuaSauce about 10 keV
23:08 robotustra no gamma radiation or mesons?
23:08 GargantuaSauce gamma radiation is not part of the solar wind
23:08 robotustra no electrons?
23:09 robotustra ok, any other irradiations?
23:09 robotustra useful for human health on the orbit?
23:09 robotustra who spent the longest time on the orbit?
23:10 robotustra Krikalev
23:10 robotustra and do you know why he is alive?
23:10 robotustra because magnetic field of Earth protected him
23:11 robotustra do you know how long to fly from Earth to Mars?
23:11 robotustra eh?
23:11 GargantuaSauce depends greatly on the propulsion technology used
23:11 robotustra so
23:11 robotustra tell me the number of days
23:12 robotustra they will use human propulsion technology
23:12 robotustra and it will take about 500 days
23:12 robotustra without Magnetic field of Earth
23:13 robotustra what shield are you talking about?
23:13 robotustra they all will dead
23:13 robotustra it's one way ticket
23:14 robotustra good shield would be very heavy
23:14 robotustra but heavy things it's difficult to accelerate and difficult to break
23:15 robotustra so, thare a lot of unsolvable problems to solve
23:15 GargantuaSauce project orion could have taken 800 tons of payload to mars in a 175 day round trip
23:16 robotustra good luck
23:17 robotustra give me a link
23:18 robotustra 175 days at what speed?
23:18 robotustra cremline dreamers
23:18 GargantuaSauce http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20000096503_2000138021.pdf
23:22 robotustra it's a CONCEPT
23:22 robotustra where is working prototype?
23:22 GargantuaSauce politics, not technical limitations, got in the way
23:23 GargantuaSauce for whatever reason the only kosher use for nuclear devices is pointing them at people
23:23 robotustra astronauts will die and electronics will go crazy because of self radiation there
23:23 GargantuaSauce yeah i'm sure they totally forgot to take that into account
23:24 robotustra how they will start from earth on this engine?
23:24 robotustra they gonna to make another Chernobyl on the earth?
23:25 GargantuaSauce assemble in orbit
23:25 GargantuaSauce would take 3-4 delta IV launches
23:25 robotustra and assemble stuff in space?
23:26 robotustra do you know that any nuclear explosion creates huge EMI in space?
23:26 robotustra they fuck up all tele communication on earth
23:27 robotustra and all suttelites
23:27 robotustra satellites
23:27 robotustra this concept is FAKE
23:27 GargantuaSauce so accelerate it into a supersynchronous orbit with chemical thrusters first
23:27 GargantuaSauce there is not a huge amount of delta v in that
23:28 robotustra 175 day is too much
23:29 GargantuaSauce if only we had some way to generate magnetic fields
23:29 robotustra even if they'll fly at 100 km/s
23:30 robotustra I go sleep. good night
23:30 GargantuaSauce it would certainly be a huge endeavor
23:30 GargantuaSauce but the concept is conidered feasible i believe
23:33 rue_house :) motor drivers, I have wonderfull motor drivers
23:34 GargantuaSauce all 18 done?
23:36 rue_shop3 not fopr the hexapod
23:36 rue_shop3 all the motor drivers were done for buddy a long time aho
23:36 rue_shop3 its generic motor drivers for everything else
23:36 rue_shop3 the cnc machine and robot arms
23:37 GargantuaSauce ah
23:42 rue_shop3 wildmage, think I could make a balancing stick based on that flywheel thing with my standard servo loop controller code?
23:49 wildmage rue_shop3, can you do full rotations?
23:50 wildmage that's the key... speed control, metered rotations
23:56 rue_shop3 I just assumed you apply a current level to the motors and derive the acceleration from that
23:57 rue_shop3 but if its closed loop, knowing the state of the flywheel shouldn't matter, as long as your already balanced anyhow
23:59 GargantuaSauce current:torque is not constant
23:59 GargantuaSauce nor is torque:acceleration perfectly constant