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DARPA Puts $32M Toward Quadruped Robot Prototype

timothy posted more than 4 years ago | from the either-that-gives-you-heebie-jeebies-or-it-doesn't dept.

Robotics 64

The Installer writes with this selection from GizMag: "Walking quadrupeds are being cast to play a major role in the rapidly unfolding age of robotics. The platform promises versatility far beyond that of wheeled-vehicles and will undoubtedly find applications in a wide variety of fields. Not surprisingly, the development of quadrupeds is being driven by the military and DARPA has recently boosted its efforts by awarding Boston Dynamics $32 million for the prototype phase of its Legged Squad Support System (LS3) program. ... LC3 is conceived as an autonomous support pack-robot for ground troops that can carry 400 pounds or more of payload, sustain itself for 24 hours and cover 20 miles in almost any kind of terrain."

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64 comments

Greetings my mechanical hightech Overlord (0)

Anonymous Coward | more than 4 years ago | (#31208732)

I for one welcome our AT-AT overlords.

and.... (0)

Anonymous Coward | more than 4 years ago | (#31208734)

So it begins....

Why four legs? (3, Insightful)

immaterial (1520413) | more than 4 years ago | (#31208762)

Wouldn't six be more stable, distribute weight better, and be more redundant in case of failure of a limb? The only advantages I can think of to four is better efficiency (maybe? Having to move fewer limbs should be a plus, but on the other hand they'll each also have to be more powerful) and a slightly more compact form. Is it worth it? I'd certainly find a couple extra limbs convenient; you'd think a military robot in potentially harsh conditions would also find a couple spares very useful.

Re:Why four legs? (0)

Anonymous Coward | more than 4 years ago | (#31208804)

have a look at the videos of this robot in action, extra legs would simply be superfluous. Also, wouldnt eight legs be better then six? where do we stop :P

Re:Why four legs? (1)

goldaryn (834427) | more than 4 years ago | (#31208826)

Wouldn't six be more stable, distribute weight better, and be more redundant in case of failure of a limb?

Extra limbs are a whole extra level of complexity in terms of limb control and present extra vulnerabilities as well as extra benefits. Like with anything, limbs present diminishing returns; millions of years of evolution has settled on 4 limbs as a good number for a large land creature.

Or, if you prefer "God made it that way".

Or, "4 legs GOOD, 6 legs BAD"

Re:Why four legs? (1)

goldaryn (834427) | more than 4 years ago | (#31208848)

Quick joke: What has 3 heads, 2 arms, 2 wings and 8 legs?

A man sitting on a horse with a chicken on his head

Re:Why four legs? (5, Interesting)

immaterial (1520413) | more than 4 years ago | (#31208908)

Well, was there a time when vertebrates ever had six limbs? I thought we'd just happened to pop out of the water that way; given that we vertebrates have all kept our basic layout since then, I wouldn't really say evolution ever had the opportunity to try six limbs on a large land creature.

Obviously more legs doesn't necessarily mean better. Why not eight, like the last guy said? There's an advantage to redundancy but like you said there are disadvantages as well. It just seems to me like six would be a happier medium between the two.

You need three points on the ground to remain relatively stable without getting into balance issues. Of course a good robot could balance itself on two - hell even a Segway can do it - but lets say in a complex situation like trying to climb a steep rocky hill in Afghanistan in a hurry you want as much stability as possible (note a person in that situation will be using their hands for additional stability too). To move while doing that requires at least one more limb, for a total of four. If there is have a failure in just one limb, you've reduced the robot's stability by quite a bit. I just seems to me like six would be worth it in varied terrain - I mean, if all you're going to do is bound across the plains all day like a gazelle the extra limbs may not be useful, but I'm imagining these things in more steep, mountainous areas as well, where extra footing could be a huge asset.

Re:Why four legs? (1)

biryokumaru (822262) | more than 4 years ago | (#31209590)

Well, the way in which a Segway balances is not exactly comparable to the manner in which a biped balances. What with the wheels and all.

Re:Why four legs? (1)

Dachannien (617929) | more than 4 years ago | (#31209604)

but lets say in a complex situation like trying to climb a steep rocky hill in Afghanistan in a hurry you want as much stability as possible (note a person in that situation will be using their hands for additional stability too)

This, of course, is why mountain goats have six legs.

Re:Why four legs? (1)

argent (18001) | more than 4 years ago | (#31209668)

There is no evolutionary mechanism for mountain goats to acquire additional legs.

Re:Why four legs? (1)

timeOday (582209) | more than 4 years ago | (#31209776)

Debatable. But there certainly is an evolutionary mechanism for animals to lose 2 legs - simply by standing erect - and many have.

Re:Why four legs? (1)

argent (18001) | more than 4 years ago | (#31209990)

We're not talking about re-purposing limbs, we're talking about changing the number of limbs completely. There are a few examples of animals that HAVE completely lost limbs, but there are still occasional cases of vestigial limbs in snakes and whales. There's no examples or evidence in genetic or archeological history of any species derived from the earliest land animals with more than four limbs, so the evidence is overwhelming that the number of limbs was genetically set long before there were any land vertebrates... large six limbed animals have not even been (metaphorically) "tested" by evolution.

Re:Why four legs? (1)

timeOday (582209) | more than 4 years ago | (#31216118)

We're not talking about re-purposing limbs, we're talking about changing the number of limbs completely.

I'm not. Arms are not legs. The fact that some large land animals (us & our near relatives) went from 4 to 2 casts doubt on the idea that 6 would be better than 4.

Re:Why four legs? (1)

Nivag064 (904744) | more than 4 years ago | (#31216932)

We have 4 limbs same as a horse, but in our case two are specialised legs and the other two can be used as legs or as specialized manipulation devices.

As has been said elsewhere, evolution of land mammals and reptiles occurred after 4 legs had become the maximum. For such complicated organisms, evolving six legs would have meant a prohibitive number of individuals in vastly uncompetitive configurations for lots of generations, so much so that the probability of winning your favourite lottery every year by chance for your life would be much more likely!

Re:Why four legs? (1)

argent (18001) | more than 4 years ago | (#31217510)

The issue is not "are there circumstances where fewer legs are better". There are circumstances where NO legs are better (whales and dolphins, for example), and there are circumstances where at least four legs are necessary (any climbing animal, where there's a need for a 'moving tripod' gait) and more would be desirable (look at all the animals, including our relatives, with prehensile tails).

It is "if there are circumstances where six or more legs would be better, why don't we see large six-legged land animals". The answer is "there's no mechanism by which they could evolve".

Re:Why four legs? (1)

Dachannien (617929) | more than 4 years ago | (#31210146)

True, but if having only four legs while clambering around on a mountain was truly that great a deficiency, then mountain goats would not have evolved to include mountains as part of their habitat.

Re:Why four legs? (1)

argent (18001) | more than 4 years ago | (#31213456)

Evolution is not a directed process. It finds local optima, an organism can't arbitrarily jump from one local peak to another, can only (and ironically in this case) climb the hill it finds itself on. It's not that four legs are a deficiency, it's that downplaying the possibility that six may be an advantage because an algorithm that wasn't able to experiment with six legs in a particular problem space didn't develop it is likely short-sighted.

Re:Why four legs? (1)

Patch86 (1465427) | more than 4 years ago | (#31209636)

Erm, well there are lots of animals which have different numbers of legs (crustaceans and insects 6, arachnids and cephalopods 8, etc.). Over the course of billions of years, most designs have been given a chance at competing in most areas.

I don't think it can be a coincidence, completely outside of the mechanics of evolution, that more than 4 legs are prolific in small animals (crabs and large bugs at the largest) while most larger animals have gone for 4 or less. Arguing that this has absolutely nothing to do with natural selection would be a difficult standpoint.

Re:Why four legs? (1)

argent (18001) | more than 4 years ago | (#31209696)

I don't think it can be a coincidence, completely outside of the mechanics of evolution, that more than 4 legs are prolific in small animals (crabs and large bugs at the largest) while most larger animals have gone for 4 or less.

The reason that large land animals all have four legs is likely nothing more than chance.

All large land animals are evolved from a common ancestor that acquired the traits allowing them to become large land animals (such as an internal skeleton) BEFORE they came onto the land. One of the traits that they brought with them onto the land was the four fins of the ancestral fish.

Re:Why four legs? (1)

nameer (706715) | more than 4 years ago | (#31212040)

A pogo-stick is effectively a balanced 1-leg system. Marginally stable, but doable.

Re:Why four legs? (1)

Nivag064 (904744) | more than 4 years ago | (#31216898)

I agree that having 6 legs would be good, armoured cars have 6 wheels rather than just 4 for the same reason for improved redundancy (ege better able to operate with one or more wheels/legs out of commission). Also as you have said, it would make it easier to cope with rugged terrain.

I think that normally 8 would be overkill, also more legs are not necessarily be better as they would have to be lighter and more easily damaged by enemy activity. However, I think 4 legs is too few.

I have thought about this problem on and off since I was about 6, when I saw a picture of a six legged vehicle and wondered how it moved.

Re:Why four legs? (1)

AmericanInKiev (453362) | more than 4 years ago | (#31231112)

Uh, Evolution has had plenty of experience with hexapods (spiders) and a plethra of arrangements, some less than symmetrical (crabs).
Very often, extra limbs are more valuable for manipulating food, than for motivation and become "arms", "claws", etc...

I'll bet they could have offered a prize of 1/10th that amount and got 10 better designs.

Re:Why four legs? (1)

DoninIN (115418) | more than 4 years ago | (#31212318)

4 Limbs is a good number, I'm not going to dispute that part.
But the way you say "Evolution has settled on 4 limbs" you make it sound like there's been a lot of trail with 5 6 7 13 or whatever. Your fishy little tetrapod (Someone who knows the right terms should bail me out here.) pre-amphibian ancestors just got lucky. They, and the whole suite of their adaptations were found to be suitable to flop in and out of the water and survive. This is not to say that there's anything superior about 4 limbs as opposed to 6, 8, 5, 3, whatever. The single most dominant animal on the planet primarily gets around on 2. There's a tremendously successful type of things running around with 2 legs and 2 wings. There are almost certainly far more little tiny 6 and 8, and even more legged critters than 4 legged ones... Well you get my point.

Hexapodia as the key insight. (1)

argent (18001) | more than 4 years ago | (#31209654)

Crypto: 0
As-Received-By: OOB shipboard ad hoc
Language-Path: Arbwyth->Trade 24->Cherguelen->Triskweline, SjK units
From: Twirlip of the Mists
Subject: Blighter Video thread
Keywords: Hexapodia as the key insight
Distribution: Threat of the Blight
Approved: yes
Date: 8.68 days since Fall of Relay

I haven't had a chance to see the famous video from
Straumli Realm, except as an evocation. (My only
gateway onto the Net is very expensive.) Is it true
that humans have six legs? I wasn't sure from the
evocation. If these humans have three pairs of legs,
then I think there is an easy explanation for
--MORE--

Re:Why four legs? (2, Informative)

Animats (122034) | more than 4 years ago | (#31223702)

No, four legs are better for a large machine. There's a tradeoff between leg working envelope, vehicle length, and top speed.

There was a big fad for six-legged insect robots in the 1990s, led by Rod Brooks at MIT. Those were very slow, very dumb, and had a very wide stance. Six legs don't scale up well. One big issue is inertia.

Double the dimensions of something, and it gets four times as strong (strength comes from cross-section) but eight times as massive (mass comes from volume.) This is called the cube-square law, and it's why there are no giant insects. For small creatures, forces like surface tension matter, but inertia doesn't. For large, fast ones, inertia dominates.

Before dynamic balance was figured out, robots tended to have very wide stances, and some had too many legs. DARPA built funded the Adaptive Suspension Vehicle [amazon.com] at Ohio State in the 1980s. 28 feet long, six legs, seats one, no cargo capacity. Top speed 3-5 MPH on flat ground. At least three legs were on the ground at all times, and often four, five, or six. The gaits were very conservative. It was supposed to be off-road capable, but that part never worked. A sloping road was as far as they got. There was some computer control, but the thing was mostly driven by an onboard driver, using three joysticks.

With dynamic balance and traction control, the leg geometry doesn't have to be as conservative. BigDog's leg geometry is four legs with three joints each, a narrow stance, and control which allows the leg envelopes to overlap. This is close to the layout of the larger quadrupeds. (BigDog has the size and weight of a medium pony; it's bigger than dog-size.)

With four legs and a long body, pitch stability isn't too hard, but roll stability requires active control. The faster quadrupedal mammals have very narrow stances; a horse's track is less than a foot wide, narrower than its body. BigDog doesn't track quite that narrow, but it gets close. The narrow track makes tight turns possible, and allows sudden changes in yaw when needed for slip recovery or collision avoidance.

With dynamic balance and slip control, the speed can be cranked up. The six-legged machines mostly crawled; the modern four-legged machines trot, and some run. (The usual running gaits, the ones with a moment of suspension, for a quadruped are the trot, pronk, rotatory gallop, and canter. BigDog can trot and pronk; it may be able to do a rotatory gallop.) That's the real reason to go with four legs. Six legs just get in the way at speed.

BigDog's three-joint leg [animats.com] isn't mentioned much, but the third joint lets the control system adjust the ground contact force vector to stay within the friction cone, without changing the foot position. This is a big win when climbing hills, and the hind end needs to come under the body.

It's all about the control algorithms. Don't let the legs collide, prevent slip, recover from slip, support the body, maintain roll balance, provide propulsion, avoid obstacles, stay on course, accomplish the mission. Those are the priorities.

If you want to understand the theory behind BigDog, read Didier Papadoupolis's thesis [martinbuehler.net], "Stable Running for a Quadruped Robot with Compliant Legs". The technology for BigDog came from Martin Buehler's lab at McGill University. Buehler himself quit McGill and went to work for Boston Dynamics as the chief engineer on BigDog. (Once BigDog worked, he went to iRobot.) The theory is out there in the literature. Some of it is mine.

Duplicate story (5, Informative)

ajknott (313187) | more than 4 years ago | (#31208766)

Re:Duplicate story (1, Funny)

beef3k (551086) | more than 4 years ago | (#31208850)

you must be new here... it should be more like:

DUP3!
1. Post dupe on Slashdot
2. ????
3. Profit!

In soviet russia you dupe slasdot!

LC3 = LS3 = Halo-headed-robot-dog; (0)

Anonymous Coward | more than 4 years ago | (#31208900)

that is all

Congratulations (4, Insightful)

srussia (884021) | more than 4 years ago | (#31208966)

from TFS: LC3 is conceived as an autonomous support pack-robot for ground troops that can carry 400 pounds or more of payload, sustain itself for 24 hours and cover 20 miles in almost any kind of terrain

They just specced a camel!

Re:Congratulations (0)

Anonymous Coward | more than 4 years ago | (#31209120)

A bullet proof camel with capacity of carrying 2 rocket launchers and a minigun.

Re:Congratulations (1)

peragrin (659227) | more than 4 years ago | (#31209484)

um I have never seen a bullet resistant camel before.

That is the big difference between this and real animals the ability to survive(or easily repaired) after being shot

No, this thing needs fuel (1)

Colin Smith (2679) | more than 4 years ago | (#31209976)

A camel will eat anything semi green.

(and can be bought for the meagre price of your wife, or $500, whichever comes first)

 

Re:Congratulations (0)

Anonymous Coward | more than 4 years ago | (#31210026)

Get this guy on the team

http://www.youtube.com/watch?v=O3ovrT8pWww

Re:Congratulations (1)

bill_mcgonigle (4333) | more than 4 years ago | (#31212286)

They just specced a camel!

Can a camel be stored in containers, air-dropped from autonomous under-radar aircraft and fitted with remote controls, heavy weaponry, and multi-spectral vision?

OK, that would probably get DARPA funding too, but I think the point stands.

Re:Congratulations (1)

couchslug (175151) | more than 4 years ago | (#31213538)

"They just specced a camel!"

I put my assigned camel in War Reserve Material (WRM) storage, properly wrapped with desiccant packs, then charged the container with dry nitrogen.

When my unit deployed, we opened the box, but camel was all wrinkly, very quiet, and wouldn't get up. Attempts to jump start it off a slave cable from my truck were unsuccessful. The design needs work.

quirks of language (0)

Anonymous Coward | more than 4 years ago | (#31209176)

"Wheeled-vehicles"? Do those resemble wheeled vehicles? Curious, I just saw that bizarre twitch of reflexive hyphenation on Boing Boing. You're outed, Timothy. You're Cory Doctorow.

Get English lessons.

the better to (thou shalt not?) kill you with? (0)

Anonymous Coward | more than 4 years ago | (#31209488)

just what we need? more&more impersonal methods to destroy each other, & a world that does not belong to us. eases some of the potential guilt involved.

it would seem the self-serving 'laws' of man'kind' are not quite aligned with the process of the big flash. there will NEVER be a better time to consult with/trust in your creators (maybe even your parents/elders).

no need to confuse 'religion' with being a spiritual being. our soul purpose here is to care for one another. failing that, we're simply passing through (excess baggage) being distracted/consumed by the guaranteed to fail illusionary trappings of man'kind'. & recently, (about a 2000 years ago) it was determined that hoarding & excess by a few, resulted in negative consequences for all.

the lights are coming up all over now. see you there?

boeing, boeing, gone.

needs a ton more work (0)

Anonymous Coward | more than 4 years ago | (#31209570)

no - one is going to wait for that mincing donkey to catch up in a combat environment, plus it would be a prime target and a sitting duck for anyone with any foresight

crpl Jones: hey sarg! our packmule machine thingy just got shot up, it's stuck out there in the open with all our gear and ammo, and the radio...

Sarg: well volunteered Jones, bring back the radio first and I'll send for a mechanic...

crpl Jones: duh!.

useful? more use if it could do the combat and the soldiers stay in cover and issue orders, fit some guns to it.

Re:needs a ton more work (1)

Spatial (1235392) | more than 4 years ago | (#31210252)

No shit it needs more work. What do you think the money is for?

Re:needs a ton more work (0)

Anonymous Coward | more than 4 years ago | (#31211304)

Hopefully the money will get that Battle Integrated Tactical Contrivance Hauler prototype going from a silly looking pokey canter to a decent trot. If they can get it to gallop and leap like a gazelle, then it would also be worth putting a gun on. I'm sure military geniuses can imagine a wheeled support vehicle driving up somewhere adjacent to rough terrain, and having a dozen of these things unfold and deploy from the sides to quickly do an area sweep instead of regular soldiers.

Seems obvious they got the stability part down, but the mobility part seriously needs more work. I'm curious as to whether $32M is enough to foot the bill. But as it is now, it seems a long way off from being kill-bot material.

"Legged Squad Support System" == LC3? (1)

tqk (413719) | more than 4 years ago | (#31211654)

... prototype phase of its Legged Squad Support System (LS3) program. ... LC3 is conceived ...

LC3? Where'd that come from?!? Why do so few of you submitters ever bother to re-read your own submissions? Assuming you can read.

Is Forth behind this robotics explosion?? (1)

dukesterr (1750080) | more than 4 years ago | (#31211956)

Just wondering if Forth - or the so-called "Toilet Flushing Forth", to the Forth community's friend -- "werty" - is the programming language enabling these modern day robots? It would be about time after a 30 year hiatus from moving a telescope in Arizona. Better late than never, I guess. ;)

I am scared. (1)

dadelbunts (1727498) | more than 4 years ago | (#31212224)

I hope you have all seen the big dog vidoes. If not here. http://www.youtube.com/watch?v=W1czBcnX1Ww [youtube.com] Imagine waking up in the middle of the night to the loudest bee sound you have ever heard. Only its not bees its thousands of those things with guns strapped on their back. This is what i dream about at night.
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