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New BigDog Robot Video
Posted by
kdawson
on Wednesday March 19, @03:01AM
from the now-to-work-on-the-muffler dept.
from the now-to-work-on-the-muffler dept.
John860 writes "The US company Boston Dynamics has released an amazing new video of its quadruped robot BigDog. The highlight of the video (at 1:24) shows how the robot starts slipping on ice, almost falls several times, but finally regains its balance and continues walking. The video also shows the robot's ability to cope with different types of terrains, climb and descend steep slopes, and jump. Two years ago, the older version of BigDog was already able to climb slopes, keep its balance after a strong kick, and walk on rough terrain like stones, mud, and snow. The new version weighs 235 lbs and can carry a payload of up to 340 lbs, a factor of 4 better than its predecessor."
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Robotic 'Pack Mule' with Impressive Reflexes 268 comments
moon_monkey writes "New Scientist has a story about a nimble, four-legged robot that can recover its balance even after being given a hefty kick." From the article: "The project is sponsored by the US Defense Advanced Research Projects Agency (DARPA), who want the robotic pack mule to assist soldiers in terrain too tough for vehicles. Ground-based soldiers often need to carry 40 kilograms of equipment. Raibert says the latest version of BigDog can handle slopes of 35 - a steeper gradient than one in two. The hydraulics are driven by a two-stroke single-cylinder petrol engine, and it can carry over 40 kg, about 30% of its bodyweight. The robot can follow a simple path on its own, or can be remotely controlled."
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sorry (Score:5, Funny)
The walking motion is much like a goat. A goat, see?
Re:sorry (Score:4, Funny)
Goat.mechs?
Somewhere deep in the caves of Tora Bora (Score:5, Funny)
Yeah, but it was delivered by this weird mechanical goat thing that buzzed like a swarm of bees in a poppy field.
Hmm. I believe my RealGoat delivery has arrived! Allahu Ackbar!
Re: (Score:3, Insightful)
Re:Somewhere deep in the caves of Tora Bora (Score:4, Funny)
When it gets real they sent the the dogs out, but because the dogs was trained with russian equipment, they prefer to lay below the russian tanks and not the germans.
Creepy (Score:5, Interesting)
Re:Creepy (Score:5, Interesting)
They may have to think about toning this aspect down for war time scenarios - I can well imagine soldiers going to 'old yella's' assistance when he comes under fire!
Re:Creepy (Score:4, Informative)
Re:Creepy (Score:5, Informative)
Yes, it's called the "Uncanny Valley [wikipedia.org]".
Simply Amazing. (Score:5, Interesting)
Re:Simply Amazing. (Score:4, Insightful)
Add a turret, a video camera, and a remote control -- presto, a soldier that can march 24/7 across the desert, across the ice, through tear gas clouds, through radioactive fallout, and arrive somewhere all fresh and ready to shoot people, or drop bombs.
They're not going to "make toy versions", at least not any time soon. Why try to make a $100-1000 toy, and compete on the free market, when you can keep everything secret and sell them to the military for orders of magnitude more?
I'm an American, and these things scare me. Robert E. Lee once said "It is well that war is so terrible, or we should get too fond of it". Our government is making it significantly less terrible (for its own soldiers) all the time, and they also seem to be growing rather fond of it. When you can run a robotic war (in the air and on the ground) by remote control, what's to stop you from attacking everybody you don't like?
I predict we'll have robot infantry on the ground inside of 5 years, and within 2 years of that, they'll be back here patrolling American soil. And no, it's not a partisan issue, either: even Obama, the democratic frontrunner, wants to *increase* military spending, even though America's military budget is already larger than the military budgets of every other country in the world, combined.
Re:Simply Amazing. (Score:4, Insightful)
And this could be likely achieved with other conventional robotic conveyance mechanisms. If you just need to deliver a mobile land-mine, adaptation of simple RC cars could probably serve. As for dropping bombs and shooting people - there are plenty of airborne weapons that would be difficult to surpass in terms of "efficiency". Cheaper and simpler will win.
About the only military use I can see for this might be urban alley crawls, where terrain could be difficult, cramped, and dangerous, and possibly IED detection/detonation. I agree with parent about this being mostly a pack mule.
Re:Simply Amazing. (Score:5, Insightful)
If a robot is cheaper than a dead/wounded soldier the robot might be a better option.
Also consider that robots need no training and (almost?) no supplies when they are in storage.
Re:Simply Amazing. (Score:5, Funny)
Sounds like maybe we should call PETA on you, since it sounds like you know exactly how an animal reacts when it gets violently kicked
Re:Simply Amazing. (Score:5, Funny)
No tactical need for anti-tank or self-detonating (Score:3, Insightful)
One small step for a dog (Score:5, Funny)
True Test (Score:3, Interesting)
This is bigger than you think (Score:4, Interesting)
Cool, yes. Useful? (Score:4, Interesting)
Since it needs to be able to exert pretty big forces very quickly, I doubt they're going to lower the power requirements, so I highly doubt they're going to be able to use a quieter power source like batteries or fuel cells. Nothing beats the power-to-weight ratio of internal combusion.
Me, I'd go with a real live mule instead for all applications you'd use this in. Same payload capacity, not much bigger, totally silent, self-refuelling, costs $hundreds rather than $hojillions.
Re:Cool, yes. Useful? (Score:5, Insightful)
How it works - some technical details (Score:5, Informative)
This is very nice work. It's good to see Raibert doing robotic locomotion again, and finally, with a big enough budget.
Back in the 1980s and early 1990s, Raibert headed the MIT Leg Lab, which produced the first legged robots with real balance control. Raibert started with one-legged hopping machines, to force the balance issue. His big insight was that balance is more important than gait. In 1992, he left MIT and did a startup, Boston Dynamics, and went off into simulation. Most of the simulations weren't dynamic, just kinematic. Now he's back to robotics, and dynamics, again.
I've worked on control of robot running on rough terrain [youtube.com]. So I understand the problems. Watching the Big Dog video, I have a reasonably good idea of how it works. This is quite impressive. DARPA got its $40 million worth.
First, it has slip control, like automotive ABS, for its feet. The first insight on the hard cases for locomotion is that balance is more important than gait. The second is that slip control is more important than balance. The key to slip control is keeping the transverse forces at foot-ground contact below the point where the feet break loose. ("Inside the static friction cone", for those familiar with the terminology.) Watch it move on ice. The feet do not slip at all unless there's real trouble, as when someone kicks the thing. The transverse forces are being held below the break-loose point. Given the load on the foot, the actuator forces (hydraulic cylinders on Big Dog) must be coordinated to keep the transverse force below the ground coefficient of friction times the longitudinal load. Finding the ground coefficient of friction can be either trial and error (if it slips, reduce the value) or they may have actual slip sensing in the foot, like humans and animals. Humans, incidentally, tend to maintain a contact force about 20% above the break-loose point, as a safety margin.
Big Dog's reaction to a slip is to immediately raise the foot and go for a new foot placement. That's an emergency behavior, though; it's the prevention of slip that makes it work. Watch the robot's reaction when it slips on ice, and, once you know what to look for, you'll see how it does it. The first priority is to recover traction. As soon as a foot slips, it's lifted and placed in a new position. The second priority is to recover balance. As the robot starts to roll to the right, it executes a violent twist to the right and throws out the right front foot. It needs a foot position within the traction limits to provide the roll moment needed to recover balance, and it has a good enough planner to find one. Look at that sequence and ask yourself first "where does the foot need to be to get traction", then "where does the foot need to be to recover balance". Then you'll understand how it works.
Big Dog has, finally, true gaitless locomotion. Decades of locomotion research have focused on gait, foot sequence, "central patten generators", and similar mechanisms that deal with the easy cases. Wrong answer. The right answer is to think of legs as assets that can be deployed to maintain slip and stability criteria. It's very clear that Big Dog does this; it can use its feet (and knees!) as necessary. It's not constrained to a gait pattern at all.
There's a true dynamics predictor and planner in there. This is not just a reactive robot, like Brooks' little machines. Nor is it a straightforward ZMP ("zero moment point" [wikipedia.org]) stabilization system, like Asimo. (Think of ZMP as a generalization of center of gravity to include momentum.) There's a planner with a horizon of (I think) about two foot placements ahead, and it has "what if" internal simulation capability. That's why this robot moves so well. It can predict, at least approximately, what's going to happen for its next move, and plans on that basis. That's why its movement are so smooth. Without that, you'd see big changes in strategy between foot placements. It doesn't do that, which tells us there's a dynamics planner in there. One with a good contact model, too; the robot will go down to its knees in a useful way if it has to.
Also notice that Big Dog has legs with three joints, not two. [animats.com] Two joints are enough to position the foot anywhere in the workspace, so why have three? The answer is that having three joints offers the option of adjusting the ground contact angle for better traction. Big Dog clearly does this, as can be seen when it's climbing hills. Very nice.
The legs can move within each other's working envelope without interfering. Notice that when the Big Dog is kicked, the legs cross, as the legs on the trailing side are used to get some additional traction and support on the leading side. The legs cross without tangling and without frantic repositioning; this was a planned move. It's also an indication that the dynamics planner does some case analysis, since it has to decide which leg should go in front of which other leg.
Boston Dynamics isn't saying much about how this works. I'm not finding any technical papers or patent applications. If you understand the problem, though, the video tells you quite a bit.
Re:Kick (Score:5, Funny)
Re:Kick (Score:5, Funny)
The civillian versions will be all plush and lovable (though huge) until some glitch reenables the combat subroutine. Lone cop and beautiful female computer scientist will then need to fight their way to the Mans' Best Friend central computer to press the reset button. One of the dogs will stay loyal and help them, the rest (with glowing red eyes, to tell the slower audience members that they are Evil) will terrorise the population.
Joe Dante will direct "Mans' Best Friend" (working title "Pastiche 3") of course, from a novel by Steven King. The cast will all be scientologists and there will be a few references to engrams and so on in the script, or maybe just adlibbed in. The movie will start with Eisenhower's speech about the Military Industrial complex and then cut to something ironic, like a weapons factory stripping the weapons off a giant robot dog endoskeleton, wrapping it in plush fur and loading it into a box labelled "Mans' Best Friend".
Re: (Score:3, Interesting)
If you took two dogs and strapped them together, facing each other, with their forelimbs in the air and only their