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Animal Robots
hamlet2600 writes "The New York Time is running an article all about how animal like robots [Soul Sucking registration required] are beginning to become more imporant in furthering research. For years reseachers have been trying to make humanoid robots, Honda's ASIMO, MIT's M2 are some notable ones. It seems that more and more researchers are turning to the animal kingdom for "simpler" means of locomotion."
Robotic penguin anyone?
My daughter and I came to the same conclusion as the researchers in this article: after struggling to make a biped robot with LEGO Mindstorms robotics for quite some time, we found that a six-legged ant was much simpler.
Every neuroscience conference I go to has at least one or two animal like robots.
Would the robot pets 'download' onto your carpet when you aren't home?
I am the lord of the pun. Dance Knave!
1.Robots don't shit or piss all over your new carpet.
2.Robots don't chew your leather couch.
3.Robots don't hump your leg (well, maybe with some creative mods they might).
4.Robots don't need to be fed.
5.Robots don't need to go to the vet.
6.If you go on vacation, you can leave the robot wherever.
I would wager, however, that a robotic dog would be quite a bit less effective in attracting ladies.
Snake robots have been around for some time www.snakerobots.com/main.htm
problem is that they have YET to design a sensor like our inner-ear to detect balance and orientation.
even animals have this "sensor" and the subprocessor systems to not tip over when a leg is lifted before the main processor can detect the change and ask for a balance correction.
too many projects are looking at monolithic processing, which can not handle a complex thing like walking and balance like an organism can.
Think about this, an animal like a dog or housecat is certianly not designed to use stairs, yet they adapt quite easily and quickly to handle them even though they were designed for human motion. A dog's rear leg has extremely limited motion compared to a human leg, yet they adapt to running up a stairwell quite easily, and some dogs can adapt to the point that they can climb a ladder!
MIT had a great program going about 15 years ago about seperating all robotic motion out to seperate processors and allow the main processor to issue interrupts to cause different motion, but I haven't heard from anyone in that program for a really long time. Anyone know if the program is still going?
Do not look at laser with remaining good eye.
Yeah, well you just described everything about a dog. Except you left out the companionship they provide. I agree, if you are too lazy to feed, walk, and clean up after the animal then don't get one get a robot. I just hope you never have kids, better buy robot children instead.
Just think, the article's mention of that Disney robot dinosaur:
Bipedal movement is more efficient than quadrapeds. It takes less energy to move the same mass at the same speed using two legs vs four. The problem lies in the inherent instability of bipedal movement. Thankfully, evolution has blessed us with the means to account for this instability. Roboteers don't have the benefit of millions of years and thus an easier solution would be to revert to the less efficient mode of movement involving more than two legs.
B O R I N G
Clickable link.
Martin
ahh, to own a superfast "rat-thing" (not to spoil the plot)
meh
Oh, don't worry, I have a dog (I adopted him from a shelter). Dogs end up at places like that because it is a lot of work to own one. I know there are a ton of people who are not responsible enough to own them, and maybe a robot dog would be a nice alternative for said people.
Well, the basic idea's been around in compsci and robsci for decades -- simple machines. The article suggests that researchers are trying to imitate certain species of existing animals, and while that is no doubt true, the point is much more basic. Animals adapt to their environs in the long run (evolution) and the short run (whatever short-term evolution is called). Copying evolutionary development (ie, the long run adaptation) is really rather pointless, unless you want a robot to perform exactly as a lobster does under the sea.
If, on the other hand, you wish to use some of the lobster's physical and electromechanical techniques to create a robot that can respond to its environment independently of its controller, then you may have something worthwhile. The dramatic success of the Mars rovers, AFAIK, is due in large part to their adaptable mobility, the main impulse paths for which were copied from insects (ants?).
So, it seems to me that article misses the point -- it's not the physical structures of animals, but the neural processes that guide them, that researchers are so giddy about copying.
Peace, Love, and Soul.
If you dont feed a dog, he will die. If you do not recharge a robot, you have no active robot for a day.
You take a dog to the vet at times whether he needs it or not (heartworm and flea checks, etc). You'd take a robot to the repair depot if it breaks.
"I would wager, however, that a robotic dog would be quite a bit less effective in attracting ladies."
That's what I'm saying. Bring puppy to the park and you attract girls. Bring a robot and you attract nerds.
I actually spent this last summer working on M2, so I can tell you a little about how it works. M2 was designed to make use of two nifty ideas, the first being Series-Elastic Actuators (photo)and the other being Virtual Model Control link to pdf journal article).
The series elastic actuators are meant to simulate the interaction of a human muscle-tendon-bone system, and to allow for the design of a low-impedance system. M2 is designed to actually mimic the inherent low-impedence (low-stiffness) mechanical system that people represent. People are really awful at position based/high-impedance control, which is what most traditional robots use. This is useful for manufacturing, when you want the robot arm to always put the bolts in the same place, but leads to stereotypical "robot" movement (like the guy spastically jerking around on the dance floor). People are pretty good at force control though (there are all sorts of biological reasons for this). So M2 was built to be low-impedance like a person by using these S-A Actuators.
Virtual Model Control is supposed to allow more a more intuitive control of a robot by simulating it as a mechanical system. VMC lets you basically define springs and dampers at different points which are then simulated by the actuators. So to keep M2 standing, you might make a granny-walker out of springs, and to make it walk you could "attach" a spring to its chest pulling it forward. VMC has been implemented in simulation (where it works great), but it's not quite ready in real life.
The really cool thing about M2 is its potential. It already moves much more fluidly and naturally than any other robot out there, and its not nearly done yet. Once its working properly, it'll be able to walk essentially blindly (becuase its low impedance) like a person, rather than needing to know exactly where to place each foot (*cough*ASIMO*cough*) to keep from shattering itself.
If anyone has any other questions about how M2 actually works, I'd be happy to answer them.
-Zach
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Here is a no registration link to the article. This link was generated by New York Times Link Generator.
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The Ambulatory Robotics Lab at McGill develops several robots, including a series based on cockroaches. They work really well... I'm biased, my girlfriend is doing her masters about one (aqua).
I think they have been slashdotted once already... They've got video of the robots online.
If interested, try: http://www.cim.mcgill.ca/~arlweb/Welcome.html
IMHO, these are damned cool!
Raibert did some great work in the Leg Lab's early days. Raibert's big insight was that balance is more important than gait, and he did work with one-legged machines with springy actuators to force the issue. In his day, the Leg Lab had one, two, and four-legged running machines. But he left MIT to do a startup, which seems to have ended his dynamics work. BDI does mostly kinematic models.
The next professor to head the Leg Lab was Gill Pratt, who was more of an actuator guy. He didn't accomplish too much, and is now at some lesser school. Under Pratt, the Leg Lab backed down from running machines to walking machines.
There was somebody after Pratt, but apparently the Leg Lab is now defunct. It's sad. They made so much progress under Raibert.
It's possible to go beyond walking and running on the flat. Legs are really for traction control. All the MIT work assumes that the "feet" don't slip. That doesn't work on real hills or slippery surfaces.
There's two phases to dealing with slip. First, you need to limit joint torques to below where the feet start to slip. Once you do this, you can climb some hills. (Video, 8MB .mov file).
That work is ten years old, and still, nobody else seems to be handling leg slip at all.
The next step is to use the three joints of a leg to adjust the vector at which the normal force is applied to keep the ground contact inside the friction cone. Then you can climb more serious hills. Once you get this figured out, much of how humans move when dealing with terrain becomes clear. Leaning forward and bending the knees more when going uphill is all about slip control. Think about it.
Working on this diverted me off into physics engines, because everything that was available ten years ago sucked. So I did a physics engine that worked, which turned into a business. There are still very few physics engines good enough for legged locomotion work. Most physics engines, especially the Baraff-type impulse/constraint ones, don't do friction well. Since legged locomotion is all about managing foot-ground friction, you need a simulator that gets friction right. (Hint: if a simulator can't do a driving game without special-casing the wheel/ground contact, it won't work for legged work.)
All this is patented, of course.