-
Posts
2981 -
Joined
-
Last visited
Never
Content Type
Profiles
Forums
Events
Posts posted by Fence_Sitter
-
-
Gary_Yngve said:klenke said:
No you didn't Gary. I'm bored.
So, elaborate on this sentence:
"My current project is aimed at the mostly unsolved problem of controller reduction."
What is controller reduction?
And why is it mostly unsolved?
Suppose you have a humanoid robot. It has many joints, and it has motors on each of the joints. The robot has sensors to detect all sorts of things. How do you make the robot walk?
You have to figure out how to control each motor for each joint, based on the current joint positions and all the sensory input that you have.
Model reduction focuses on simplifying the state information so that the inputs get mapped as best as possible to the outputs (controls to observations).
Control reduction focuses on simplifying the control parameters (knobs/dials for the motors) so that control problems (which tend to be nonlinear and nasty) can be solved in a lower-dimensional (easier) space. Ideally a reduced controller should retain as much flexibility from the full controller and behave robustly.
The tricky part about control reduction is that the reduced controllers have to operate on a reduced model. One option is to do model reduction and then design a controller on the simplified model. The problem with this method is that the approximation happens at the beginning, and errors tend to compound. Ideally one would want to simultaneously simplify the model and the controller at the same time (i.e. with a closed loop between model and controller). There are esoteric mathematical methods to do this for linear systems, but extending to nonlinear systems and performing robustly is still largely open.
The other way to simplify control is to make control not necessary, that is, make the system inherently robust. A simple example would be a slinky. It tends to walk down stairs no matter what width/height the stairs are. More complicated examples have been studied in biomechanical literature.
We've explored both directions, and we've tried working with toy problems (multi-link pendulums) and with real problems (humans walking).
No killer results yet.
damn
-
nick drake- fruit tree... would have gotten better, but...
-
iain said:
Paul Simon: Graceland
Talking Heads: Stop Making Sense
Stevie Wonder: Innervisions
Orbital: In Sides
G/R: Appetite for Destruction
Dave Brubeck: Take Five
The Stone Roses: The Stone Roses
Public Enemy: Fear of A Black Planet
Nine Inch Nails: Pretty Hate Machine
Amon Tobin: Supermodified
iain, have you seen tobin live? i have achance to interview when he was at the comodore ballroom... i love all his albums, from when he was cujo till now with out fom out where... have you heard that one? some good tunes...
-
bunglehead said:erik said:
bungle
have you heard del's deltron 3030?? it is an amazing album
willstrickland and i traded a year or two ago. he gave me that and i gave him jaye-z unplugged which is another fine album!!!
Yeah, I got Deltron 3030. That is pretty damn good.
"Upgrade you grey matter cuz one day it may matter"
that was sooo 2000
-
What about someone who can't climb 5.9 sport, but can lead .10 cracks?
name one...
-
Sphinx said:
But Ryland, Evilution doesn't have V12 climbing at 60 feet.
yeah isn't it 5.9 up high? or is that mandala? n e who... lots of people crag every day for a couple hours a day... big deal... when people go on trips that they plan a couple days in advance (enchantments etc) or months or years (denali, himilayas) it is much more of a dela for them and they get much more out of it. there isno denying that you get more out of alpine clibing... if you have an amazing experience cragging... write about it, but 99.999% of my great experiences are alpine... my 2 cents
-
also i have a base in the bible and shite, but since i cared for it about as much as "atlus shurugged" i really could care less. also it seems that no matter how much i think of the jesus and his churches, i see no where that he instructed people to celebrate him. that seems like a ploy by the man to manipulate people.
your first statment is negatedby your last... if you can find one verse where this is stated by Christ i will give you a nice shiny carabiner...
-
trask said:
For some, the Bible and Jesus mean nothing. Fancy that.
that is dificult to believe if you live in this country. true it may mean nothing to you spiritually, but it should in terms of the history of this country... it gives context to the history of this country. how can you know about the cultures in middles east without knowledge of koran? if nothing more, it should be a key to the past of your ancestors and your country...
-
i too am amazed at the stunning lack of a grasp of the bible that is displayed here... i know more about the koran than most of you know about the bible! yet you still mock it. What does that say about you. I can tell you. One word: fear. poka commrades!
-
Jesus was a Nazi????
jesus was the first hippy... when one of the apostles cut off the ear of the people arresting jesus... he said "hey man! everyone chill!" and he took the ear and gave it back and said "here brother, peace" pascifist, partying uber cool hippie... too bad 99.9999 % of his followers he would be disguisted with!
-
E-rock said:
Haven't you ever seent he pictures of Jesus that the Mormons have all over their churches and on their nightstands?
that is because the mormon church used to believe that the blacks were amoung those that "were not for god and not against god" because of this they were turned black as punishment... little known fact about the LDSers... jesus was a descendant of david... he was 100% jew... jew jew jew jew jew...
-
erik said:
how many jews have blue eyes and blonde hair? and if he was in exile does that make his parent criminals? and what of the visions he had? was he a drug addict? and why if god is so powerful and pious that he expects his true worshipers to whorship him? and why do people believe in a fictional book? and why do churches require you to pay them to let you pray?
jesus did not have blond hair and blue eyes... hsi parents were running away form herod who heard the propehsy that a child was going to be the new king of the jews. he then tried to kill every child at that age and jesus' parents fled to egypt to avoid their son being killed. you boviously know very little about this 'fictional book' i dotn know where you get your aryan thing tho... reading mein kampf laterly?
-
erik said:
how can a blonde blue eyed white person be born in eygpt? i thought eypgt was part of the african continent. and i dont see too many white people born as indiginous group!
jesus was a jew who was in exile... he was born in egypt, but was not a native of the area... and i am sure you are aware that wasn't the aryan posterchild your fuhrer told you about kiss kiss luv and enjoy the beautiful day...
-
minx said:
i fail to see the problem?
mabe that a "conservative" candidate is involved with shit like this... it is kinda stretching the ideals that the moral right embrace...
-
-
MisterE said:billcoe said:
I could be off, but who knows?
Bill
Bill, you know you are off, we know you are off, so don't play naive with the sprayhounds
not naive...
do you want to PM me with a phone numbesmart!
-
Attitude said:
I found that shoulder shrugs helped reduce back issues while in a weight lifting program.freeclimb9 said:I have triggerd the pain with long weight-lifting sessions where I concentrate on shoulder exercises. I perform military press, lateral raise, and reverse fly. I also do cable rows with different grip positions and widths which work the mnuscles in the area. I'm wondering if another exercise might prevent the problem. Shoulder shrugs, or something else?also dont neglect the front... if your muscles are imbalanced, you will have troubles... when i was in track, my abs were too strong and i have to do back extensions to even it out... i suppose it is possible you have the reverse affliction...
-
-
ketch said:
I use purification tablets. Funny story though to be aware of. In 78 a buddy and I spent a few weeks in Mexico just walkin and climbin. When we came back the border patrol found our halazone tablets that had got wet. The funny little white pills in the unmarked brown bottle tested positive for LSD,Amphetimines, and Barbituates. We told the man we used them to purify our water, he said" Ya right" We got out later after a day in the pound tryin to explain.
If your gowin somewhere else keep the label on the bottle
r u for real? damn that's funny! its was U.S. slammer right? cause that would suck to be hooped in a mexican jail!
-
what is up with oregon... it seems like its bolting problems are exponentially greater than in washington, but mabe people in WA jsut know how to keep their mouths shut then they place/rip a bolt... are the disparities in bolting or merely in the atalking amoung bolters/yankers?
-
's like debating a cam and bomber nut placement....
or record/CD
-
Dave_Schuldt said:
Thanks for the link, verry nice. SAD BUT TRUE.
sustained peace overseas.yeah... that truth stings...
-
Sphinx said:
On Iain? I'll take it.
i dont think you have met either...
-
nope... leaving sat night... good luck chica!
Zeke's
in Climber's Board
Posted
you sir... have been trolled.