Origami-inspired soft artificial muscles
wyss.harvard.edu
wyss.harvard.edu
One of the great benefits of these soft actuators is that you can embed them in soft structures and then get smooth movement in multiple directions. Instead of a rigid robotic arm with a few degrees of freedom, you could build something like a snake or an elephant trunk.
Another exciting area of research (my focus) is that since these actuators are fairly cheap, you could make lots and lots of robots with them. Think thousands. If you had a swarm of 1000 small robots, each of which has minimal power and sensors, what would you do with it? How would they coordinate their behavior? How would they communicate? For that matter, how would you even turn them all on? Swarm algorithms are fun to think about on robots, but are also useful for other problems out in the normal world.
(Don't focus on the "1000x" claim. It's true depending on how you measure, but it's not the exciting part.)
I'm asking because the statement [edit: in the article] that "designing how the skeleton folds defines how the whole structure moves" makes me think that perhaps the range of motions each muscle can perform is limited by construction.
Ahem. That's not to downplay the obvious usefuleness of such a device. As far as I'm concerned t's the first time in ages I find a robotics piece of news cool.
The speed seems much slower than that of an actual muscle. Is this inherent in the technology or just a limitation of the current prototypes?
I wonder also what all this means for more, let's say, traditional robots- like the ones we often see from Boston Dynamics. I guess it's still early to say but if I understand this correctly, people can now make cheap, light robots. Where does that leave heavy, expensive ones?
It's not a rhetorical question- Ferrari and McLaren didn't hang up their spanners just because Toyota and Datsun sell lots of cheap cars...
Do you need to ask? Look around, although many uses positive and negative would be found the primary two would be: espionage and “warfare” in that order.
In addition, pneumatics which this work focused on, are probably not the future. Pneumatics are not that efficient, are noisy, and are limited by the compressibility of air. The compressibility of air limits how fast these devices can actuate, their stiffness, and even how efficient pneumatic systems can get. Efficiency alone might be enough to encourage future robot makers to use something else.
Stiffness is another compelling argument against both pneumatic robots and soft robots. The max rate at which a robot can do stuff and react to things is dictated by its resonant frequency and mass. Sure we can make our robot very light, but we aren't going to be able to change the mass of things we desire the robot to manipulate. So it is still desirable to have robots with higher stiffness.
Really, a number of different technologies could make this obsolete within 50 years. For example, electric artificial muscles, slightly better rotary electric actuators along with rapid robotic assembly enabling stuff to have huge number of moving parts, or even advanced nanotechnology.
You're probably going to say that vacuum pumps are noisy/heavy next. But this doesn't need traditional high-grade vacuum pumps, very low grade will work. And of course it is entirely moot for industrial machines that stand in place.
From what I can tell the trick comes from the pleating to massively increase surface area, giving atmospheric pressure more to work with.
I've been working with robotics (as a hobbyist) my entire life. This is the most exciting thing that I've seen in a while and I'll be building prototype knockoffs all week.
If you want to re-extend one of the muscles QUICK ;)
IMO, the crucial piece of information: how much pneumatic energy is needed per unit force for one of these, compared to that of more naive designs.
They indicate that they've had a 1000x increase, which means that to lift 1kg you only need force to lift 1.001kg instead of 2kg
I'm half serious about this. The other main "artificial muscle" technology is nichrome wire after all.
A lift is not a hold. A human can hold a ton of weight against gravity, but that's not them lifting it. See the squat. You can put a huge amount of weight on your back compared to the amount you can actually move. If you put them on an escalator, they could probably even move a distance with it. But that isn't them lifting it that distance.
The human will be very flat and leaking all over, but it will be holding the containers.
But this is all incredibly silly, and what we all agree on is that they fail to consider the vacuum pump, valves and reinforced vacuum hoses in order to make their invention seem fancier.
3D printing, on the other hand, allows you to build more complex actuators (that don't necessarily apply force in a line). Origami-inspired designs (particularly rigid origami[1]) are related, in that you can design a particular folding pattern and have it fold and unfold to exert force in a particular way.
I was originally inspired by the work on artificial muscles actuated by a phase change (liquid to gas, with attendant increase in pressure) from Columbia[2]. Some combination of the two techniques might be better than either alone, allowing for fast-twitch soft actuators to fill the roles that servos stepper motors have previously occupied. Plus, they're likely to be cheaper in general, customizable to specific tasks, and probably safer in situations where humans might get in the way of the robot's motion.
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0. Most of the time I am working on reinforcement learning theory, and so building an actuator with difficult-to-model dynamics seems strange. However there's a lot RL could offer here, either learning how to control those dynamics from scratch or refining an existing model.
1. Wikipedia and its related/external links have a good overview: https://en.wikipedia.org/wiki/Rigid_origami If you just want a cool example of What Rigid Origami Can Do For You, check out: https://en.wikipedia.org/wiki/Miura_fold
2. See the press release: http://engineering.columbia.edu/news/hod-lipson-lifelike-rob... and the associated paper: https://www.nature.com/articles/s41467-017-00685-3
Paraphrasing Elon Musk's words: This is nothing. In a few years, ...
So 1000x might not be that impressive, because they are very lightweight.
And I guess it requires a big pumping device in addition to the muscle (which weight is not included in the calculation, but certainly should be).
Rather than battery and many motors, its more like motor with many transmissions and clutches. Vacuum is also a bad choice of medium... It requires stronger pumps, stronger hoses, better seals, etc.
I want to see it crush as well.