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MegaButts

They should really include a video, because without it this article isn't particularly helpful.

https://youtu.be/wwH40rYJt9g

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BattleTech nailed this decades ago. Watching this took me right back to my childhood.

Edit: AT-ST Walker, too.

It'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?

Isn'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.

Now you have me imagining mechs with human legs and it's making me uncomfortable. A bit like those "birds with human arms" photo edits.

It 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://sites.google.com/site/fineartofmechcombat/_/rsrc/146...

Wouldn't a Spider be the better scout 'Mech? It has jump jets!

Oh for sure! It just reminded me of exactly how the Locust’s legs are animated in MW5

ED209 too. But how will they handle stairs? https://youtu.be/mRDl5_-wJ0Y

Another thing that we are going to see in combat vehicles in the next decades, IMHO, is something like OmniMechs. Meaning that future weapon systems, e.g. fighters or tanks (not the upcoming generation but those after that, F-35's successor' successors) will feature LRUs (line-replaceable units) that carry different mission capabilities. That way, a fighter can land as a ground support fighter or drone controller and lift of as air superiority fighter by swapping a hand full of modules out.

It certainly sounds terrifying having an adversary that can pivot into superiority based on the situation, but I wonder how practical it would be when faced with an opponent who simply brought the right amount of non-modular vehicles in the first place?

If you have to pivot to gain air superiority, there's a really good chance that you've already lost.

I feel like in theory you’d be able to adjust the mix across the battlefield throughout the battle and it would be less about one plane’s ability to pivot.

And in theory, theory is identical to practice ;)

Everyone has a plan until they get punched in the mouth.

- Mike Tyson

Sounds super expensive and nothing a javelin can’t take care of

Like bazookas took care of Panzer IVs? I like how everyone just heard about Javelins and now thinks they rendered all armored vehicles obsolete over night.

EDIT: You now what takes care of a Javelin, or rather the guy using it? A bat or a knife.

From everything we’ve seen in warfare over the last few decades javelins and other shoulder mounted anti-tank weapons do render heavy armor highly vulnerable. New armor solutions that are even more expensive than existing ones but no more resilient against these weapons is throwing money down the drain. Sorry it fractures cherished anime fantasies.

And there I was convinced the best anti-tank weapon was a sharp Katana... Combined arms are a thing, and tanks were never well suited for urban environments. And vulnerable is the opposite of obsolete, everything and everyone is vulnerable on a battlefield.

The race between armor and anti-armor is as old as armor, it is what gave us Javelins in the first place. I don't see any reason why that is going end, ever.

Which is why nobody is going to produce something that is shiny and impressive but offers no added strategic advantage against existing counter-measures in this old struggle.

France/Germany, the US, South Korea / Turkey are launching new MBT programs at the moment, whether or not you believe the entry into service dates of 2035 for the Franco-German or US programs or not.

Not to forget that the existing models are constantly being upgraded.

That being said, shiny and impressive is usually enough to get expensive and job creating military programs of the ground, isn't it?

Looking 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?

I 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.

Well 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.

that 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.

That'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...

Hello, do you have a source for running humans elastic energy recovery being 70%?

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