17 ms·
Birds make better bipedal bots than humans do
- MegaButts 5y agoThey should really include a video, because without it this article isn't particularly helpful. https://youtu.be/wwH40rYJt9g https://youtu.be/wwH40rYJt9g
- sethammons 5y agothat is really, really cool. Leveraging spring-like "tendons" to do the leg lifting and resulting in 1/4 the power usage of "normal" robot legs modeled after humans. Great visualizations.
- Animats 5y agoThat's been done before. It's just new for Pratt, who previously used series elastic actuators.[1] Those don't do energy recovery; they fake it using a jackscrew and a stiff spring. Running humans have about 70% elastic energy recovery. Cheetahs have around 90%. What you want in a leg muscle is a spring whose spring constant, damping constant, and neutral point you can control. That can be done pneumatically (you need compressed air), hydraulically (you need hydraulic accumulators), mechanically (two springs operated by separate actuators), or electrically (a fast back-driveable motor drive that generates power during compression). All those options have been tried. There's no really good way to make a muscle-like actuator with power to weight ratios comparable to biology. Systems with a fixed spring work, but under a narrower range of conditions. [1] http://www.ai.mit.edu/projects/leglab/robots/Spring_Flamingo/misc_info/faq.html http://www.ai.mit.edu/projects/leglab/robots/Spring_Flamingo...
- garbagetime 5y agoHello, do you have a source for running humans elastic energy recovery being 70%?
- darkteflon 5y agoBattleTech nailed this decades ago. Watching this took me right back to my childhood. Edit: AT-ST Walker, too.
- duskwuff 5y agoIt's interesting that most fictional depictions of legged robots (outside of explicitly humanoid robots) use digitigrade legs. Did the artists model their art after animals which happened to have these legs, or did they subconsciously realize that this would be more effective?
- marcosdumay 5y agoIsn't it obvious? After you see an ostrich running, there is little doubt about its efficiency. Now, actually capturing that efficiency in a real system takes some really hard engineering work. Fictional robots do not need to conserve energy, compensate for impacts, etc.
- beaconstudios 5y agoNow you have me imagining mechs with human legs and it's making me uncomfortable. A bit like those "birds with human arms" photo edits.
- girvo 5y agoIt really does look exactly like a BattleMech from one of the MechWarrior video games doesn't it! Thats fascinating. Reminds me most of the Locust: https://www.sarna.net/wiki/Locust https://www.sarna.net/wiki/Locust https://sites.google.com/site/fineartofmechcombat/_/rsrc/1468738697145/home/general-guide/locust/xctl.jpg https://sites.google.com/site/fineartofmechcombat/_/rsrc/146...
- hef19898 5y agoWouldn't a Spider be the better scout 'Mech? It has jump jets!
- 5y ago
- ahaferburg 5y agoLooking at the video I can't imagine this thing achieving balance while walking. It would fall to the side immediately if you removed the guide that held it upright. This is not a walking robot yet, it's a leg design. The movement looks plausible from the side, but not from the front. It does look promising, but putting "achieves energy-efficient gait" in the title of their publication seems a bit disingenious. Putting out pictures of the thing standing - but not moving - in nature enviroments also doesn't help. Balance is the hard part. Has anybody been able to find a download link for the actual publication?
- loonster 5y agoI do wonder if it can walk backwards or handle uneven terrain. The bird likely has a muscle to extend the foot when needed, the bot does not.
- regularfry 5y agoWell yes, and they say why in the article. It doesn't yet have the degree of freedom in its hips to balance properly. That's not especially hard though - a pivot around the main spring axis would do the trick, and the dynamics of that part are well-understood at this point.
- ncmncm 5y agoTIL birds make robots. :) I always thought making robots with legs like humans was a dumb idea. Birds clearly have the right idea.
- rbanffy 5y agoThat’s precisely how I read he title. A shame. It would be a far more amusing world.
- autokad 5y agowe are built and optimized for our respective uses cases. eventually after we figure enough things out, it wont make sense to use any animal as a template. we wont need to take in any of the drawbacks the animal design has because our robot doesnt have to worry about the things animals have to worry about
- Retric 5y agoBirds had a lot longer to optimize for bipedal walking than humans did. If we had stayed bipedal without developing advanced technology it’s likely we would have gotten a lot more efficient at it over 10’s of millions of years.
- ncmncm 5y agoWe really are not optimal in any particular way. We started out as monkeys, and have done the best we could from a bad starting point. Turning the spine vertical really did not work out well at all, and knees are unfortunate at best. Probably worse than all that is how we go all to hell when we don't get exercise. Cats can sleep 18 hours a day without ever getting out of shape. Bears can can get super fat and then sleep for months, and be fine. A lot of birds can go a week without drinking or eating, working out the whole time with no sleep or even rest breaks.
- gherkinnn 5y agoYou just watch cats get fat once they hit their post-industrialisation phase.
- GauntletWizard 5y agoHow will this scale to quadrupeds? It seems novel, but birds are lightweight and topheavy, with significant active balance redistributing their weight front-to-back. Look at how much head movement is involved in a bird walking. For light loads, this may work very well, but most robotic walkers are being developed as pack animals and I think that's the clear niche for bipedal robots.
- raylad 5y agoThe head movement of birds is a mechanism for depth detection since they do not have binocular vision. By moving their heads back and forth, they can determine distance based on the rate of size increase of an object. See for example: https://www.loc.gov/everyday-mysteries/zoology/item/why-do-pigeons-bob-their-heads-when-they-walk/ https://www.loc.gov/everyday-mysteries/zoology/item/why-do-p...
- tuatoru 5y agoHave you heard of ostrich races and emu races? Birds can carry reasonably heavy loads. Quickly. Edit: much more energy-efficient than a drone delivery service, and probably not that different in speed for medium distances. The difficult problem, as with any mechanical replica of a biological mechanism (tensegrity energy recovery locomotion in this case), will be long term reliability.
- regularfry 5y agoAnd safety for bystanders.
- makeitdouble 5y agoWouldn't quadrupeds be a separate problem space with pretty different solutions ? In particular, most quadrupeds have a strategy to keep two legs touching as much as possible, which fundamentally changes the balance game.
- enasterosophes 5y agoYou seem to presume that this specific technology should scale to quadrupeds. Other people are already working on quadrupeds. You may have heard of Boston Dynamics. Not everything needs to do the same thing as everything else.
- RhysU 5y agoIs this the same mechanism/geometry of the BattleTech Marauder? https://www.sarna.net/wiki/Marauder https://www.sarna.net/wiki/Marauder
- romseb 5y agoOr Star Wars' AT-ST.
- sandworm101 5y agoBecause birds have been walking on two legs for several hundred million years, back to long before they learned to fly. Humans... not so much. It is no suprise that a bipedal prey animal would be a better runner than an ape that started standing up yesturday. We are basically the only animal that walks the way we do. The bird bodyform was already the proven betatest winner long before robots were a thing.
- ramblerman 5y agoIt's an interesting thought. I guess that also implies that the way our hindlegs bend is optimized for quad-pedal movement.
- DoingIsLearning 5y agoI don't have the evidence at hand but I am very sure from previous reading that our gait is still more energy efficient than other birds/animals. It is not about years of evolution it is about purpose. The downside is that our gait is basically a process of controlled falling, this need a really complex proprioceptive and neural control. The advantage is that we can travel _extremely_ long distances with minimal caloric intake when compared with other animals. So the claim from these researchers is that this system is efficient without the need for complex control systems (like in a human model). In practice a bird locomotor system is easier to control than a human one, it does not make the bird system more efficient because birds have been on earth longer.
- deleted 5y ago[deleted]
- deleted 5y ago[deleted]
- kayodelycaon 5y agoOur gait isn't the reason humans can travel long-distance. It's that humans have more effective cooling and don't overheat in high temperatures. In cold climates, gray wolves have advantage in ultramarathon distances, provided they don't overheat. They can maintain 5~6mph on rough surfaces. Humans maintain 4~5 mph on prepared surfaces. (Wolves are lighter and their four clawed feet have significantly better traction than our two feet.) Any surprise we domesticated dogs? They can keep up with us. :)
- awinter-py 5y agobipedal bird to beat is the ostrich anatomy of the intermediate palaeotis weigelti shows that if we're serious about this biped project, we need to move the pelvis around, fuse the shoulderblades, and reduce the # of toes + bones in the foot. (weigelti has 3, modern ostriches have 2) unclear if we'll be able to climb trees or throw things at that point -- might be able to use the neck as a sort of trebuchet https://pterosaurheresies.wordpress.com/2018/01/15/palaeotis-a-tiny-eocene-flightless-ostrich/ https://pterosaurheresies.wordpress.com/2018/01/15/palaeotis... https://palaeovertebrata.com/Articles/sendFile/270/published_article https://palaeovertebrata.com/Articles/sendFile/270/published...
- freediver 5y agoOstrich chasing cyclists https://www.youtube.com/watch?v=kotWv4MCxNI https://www.youtube.com/watch?v=kotWv4MCxNI
- bryanrasmussen 5y agoI guess it's the opposite of a dog chasing a car, that ostrich knows exactly what it will do if it catches them.
- jpm_sd 5y agoAgility Robotics has been building similar robots for about 5 years now. They have recently commercialized a full humanoid for warehouse applications. https://www.agilityrobotics.com/news https://www.agilityrobotics.com/news
- prox 5y agoWhy do these big standing robots usually have tiny tiny feet? It seems counter intuitive.
- smegsicle 5y agomaybe a smaller contact point means a simpler model that doesn't have to take the orientation of a larger foot into account?
- d--b 5y agoThat's weird, warehouses have flat floors, so robots on wheels would be much simpler.
- emteycz 5y agoOnly until something falls down on the floor or the robot needs to use stairs etc. Loading into smaller vehicles is also not done with wheels but with hands and feet.
- proc0 5y agoHmm, so birds have an AI research department now? Title could be fixed by adding "anatomy", so "bird anatomy makes better bipedal bots". Anyway, it seems reverse knee legs aren't great for upright bipedal walking, especially if you want hands to do something else. Bipedal animals with reverse knees have either wings or very small hands (kangaroo), and I would guess it's because the center of gravity with reverse knees has to be relatively low. Humans evolved to walk upright for purposes of using hands at the same time.
- olodus 5y agoAll this time we were too focused on automation stealing our jobs that we didn't realize the birds were stealing our automation-creation jobs!
- aimor 5y ago"Reverse knees" is a funny term for ankles. Penguins are another unique animal, they have very low ankles (and high knees, hence the waddling) and also seem to use their hands more than other birds. https://images.fineartamerica.com/images/artworkimages/mediumlarge/2/gentoo-penguin-skeleton-millard-h-sharp.jpg https://images.fineartamerica.com/images/artworkimages/mediu...
- iggldiggl 5y agoAnd kangaroos? Okay, so their knees are possibly somewhat more inconspicuous, but looking at a kangaroo skeleton, what to my eyes looks like their ankles also actually is their ankles. Whereas with birds the confusion comes in because a) they're walking on their toes, so what to us looks like an ankle is in fact a toe joint, and then moving further up what we think looks like a "reverse knee" is in fact the actual ankle, and b) their true knees are usually hidden somewhere beneath their feathers
- usrusr 5y agoAnd even we humans switch to "heel up" for high intensity bipedalism. Are we are secret members of the reverse knees club?
- luismedel 5y agoWe're nearer to get an ED-209 in our streets.
- daleco 5y agoIHMC has been working on various legged robots for a long time. Back in 201X, my sister team worked on a running robot inspired by Ostriches (while I was on the Exoskeleton). Looks like they are mostly focusing on humanoid and Exo now. http://robots.ihmc.us/fastrunner http://robots.ihmc.us/fastrunner Here is a video from 2017 https://www.youtube.com/watch?v=q4nvpZ6WL3U&list=PLj0k5lmLZgZbFQnrNbg5l0ruRbmRKDzUZ&index=7 https://www.youtube.com/watch?v=q4nvpZ6WL3U&list=PLj0k5lmLZg...
- tucosan 5y agoMaybe someone here has access to the related paper and could share it with the community. It's not on scihub yet. https://www.science.org/doi/10.1126/scirobotics.abg4055 https://www.science.org/doi/10.1126/scirobotics.abg4055
- ahaferburg 5y agoOne of the authors has a link on his homepage. https://www.science.org/stoken/author-tokens/ST-383/full https://www.science.org/stoken/author-tokens/ST-383/full https://is.mpg.de/person/sprowitz https://is.mpg.de/person/sprowitz
- deleted 5y ago[deleted]