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Supernumerary Robotic Limbs

76 points3 yearsdarbelofflab.mit.edu
codeulike3 years ago

I think four extra arms would be better, with some sort of onboard AI to co-ordinate their movements. You'd need some sort of inhibitor chip to stop the AI in the arms taking over the mind of the wearer though.

croon3 years ago

I'm 80% sure this is a Doc Ock reference, but not completely.

noindiecred3 years ago

Came here to see this exact comment. Was not disappointed :)

karmicthreat3 years ago

But will they be good enough to let me play T. C. Vilabier's 26th String-Specific Sonata For An Instrument Yet To Be Invented?

amarant3 years ago

Probably not, but you might be able to pull off a Lords of Excrement cover by yourself

adolph3 years ago

Certainly one would help with stealing the Heart of Gold

perilunar3 years ago

This is cool, but at the same time the discussed applications are so boring. The most obvious and exciting application (to me, anyway) would be to use the extra limbs as wings. i.e. an exoskeleton wingsuit.

paulluuk3 years ago

I think that an engine+battery that is both powerful enough to power the wings, and lightweight enough to be able to take off, is the real challenge.

brippalcharrid3 years ago

You simply await the development of nuclear isotope batteries (up to a five-order-of-magnitude improvement on chemical batteries) as a mature technology: https://apps.dtic.mil/dtic/tr/fulltext/u2/a433348.pdf

(And hope that the technology doesn't lead to a new era of arms proliferation with the use of non-fission primaries)

perilunar3 years ago

No need — regular hydrocarbons have a high enough specific energy to do the job.

The largest pterosaur, Quetzalcoatlus, had a wingspan of ~10 meters and an estimated mass of 200–250kg [1]. I don’t know how much power they could produce, but it can’t have been more than a few horsepower given they weighed less than a half a horse.

A 30cc petrol motor will easily output 2–3 horsepower, and weighs less than 10 kg. Combine it with wings from a hang glider (similar wingspan, weight ~30kg), and as long as the powertrain isn’t too heavy (compressor + pneumatic artificial muscles?), it seems possible to build something light enough to carry a human.

1. https://en.wikipedia.org/wiki/Quetzalcoatlus

brippalcharrid3 years ago

Yep, there was I under the impression that this was more of a marginal endeavour than it really is; I was probably thinking along the lines of human-powered aircraft. I'd imagine that a lot of safety problems and requirements for a very skilled pilot could be reduced in the future with computer control/brain-computer interfaces and exoskeletons.

smaddox3 years ago

What are the odds that this went classified and is already working and being used in the field?

fsloth3 years ago

I think it's exciting to first get mass production going with as many boring and mundane tasks as possible. Then those more relevant and interesting applications are easier to invent since the base population that can afford these is much larger.

jagger273 years ago

I wonder how hard it would be for a human brain to adapt to controlling 2 extra limbs? This kind of tech coupled with something like Neuralink seems like an excellent field of study.

shezi3 years ago

According to the recent article on an extra robotic thumb, people got used to it very quickly. And that one wasn't even controlled by neural link, but by sensors on the user's toes.

https://news.ycombinator.com/item?id=27218940

colordrops3 years ago

We adapt to controlling countless complex things; I'd imagine we'd adapt very quickly to controlling these.

idiotsecant3 years ago

I'm not so sure. We're good at controlling things with lesser degrees of freedom than our bodies naturally possess. I am not sure wed be very good at controlling things with more dof unless it was very high level octopus arm type control (arm, get the red ball and drop it here)

ipsum23 years ago

FPV drones are good counter-example to this.

idiotsecant3 years ago

A quadcopter has 6 degrees of freedom. A single human arm has 30 degrees of freedom.

eru3 years ago

I'm sure people will adapt, but probably not very quickly.

Of course, it depends on the level of proficiency you want to reach. But it's already hard enough for people to eg learn to play Tennis, or learn to play Tennis with their left hand, when they normally use they right hand.

jagger273 years ago

I think so too.

miej3 years ago

i believe it would be quite difficult. if you actually look at the structure of the human brain (eg the homonculus model of the cortex) you will note that a very large portion of the brain is dedicated to just the hands/manual dexterity. Many of the current neural prosthetics seem to act by attempting to leverage the brain's use of already-existing neural pathways being used for other functions. Sort of a "turn on my microwave when i open my refrigerator"-type dependence. I think a good sign of truly independent supernumerary prosthetics would be if some users reported phantom limb sensations in their absence

crooked-v3 years ago

Lots of humans adapt to fine control of cars relatively quickly, and that's through the clumsy mechanisms of steering wheel, pedals, and shifter.

JoachimS3 years ago

The human ability to adapt and incorporate tools, objects and use them naturally to perform complex tasks is so impressive and interesting.

Driving, cars, flying airplanes (including sitting 10m+ off the ground in cockpit in a 747). Things like playing ice hockey, kite surfing etc. Highly complex activities (including interacting with several others and even plan ahead), often performed at speeds way beyond what a human can move about.

jaqalopes3 years ago

Only a few more pairs until the world’s best Doctor Octopus cosplay becomes possible.

themanmaran3 years ago

Snake-like robots are already quite effective: https://www.youtube.com/watch?v=eMop3wyGC_Y

eru3 years ago

For a light hearted take on controlling a snake, try https://en.wikipedia.org/wiki/Snake_Pass_(video_game)

It's available on eg Nintendo Switch and a blast to control.

wyldfire3 years ago

Just one more pair. Doc Ock has four artificial limbs.

kleiba3 years ago

Finally, the party problem solved: one arm for holding your drink, one arm for holding a plate, and one or two arms to put some food from the plate into your mouth.

saivan3 years ago

Oh, I want to be first in line to become the first official General Grievous

theshadowknows3 years ago

First thing I thought of was “wow that would make boxing matches way more interesting.”

Baeocystin3 years ago

As seen in https://en.wikipedia.org/wiki/Megalobox :D

Sorta. Good series, though.

fnord773 years ago

there was some old movie or show where an opponent had four arms. He just grabbed the two arms of the human with two arms then started pummeling his face with his other two arms.

at the time it seemed pretty clever

modeless3 years ago

This definitely happens in Mortal Kombat (1)

fnord773 years ago

yes, that was it!

layoutIfNeeded3 years ago
fnord773 years ago

Uncanny valley vibes

kovacs_x3 years ago

Tail anyone? :D

bserge3 years ago

Ha, I've always been saying I'd like to have 4 arms like Goro from Mortal Kombat.

I guess some people actually working in this field had similar ideas :D

Though tbh having those arms on an independent robot would be much more versatile.

Alternatively, they need to have their own support (so basically, an exoskeleton) because the human body is not up to the task of supporting all the extra weight.

just_one_time_3 years ago

Guys, I was in a dark place when I saw this but the ray of sunshine this article sparked I'm feeling better than ever about the human Race!!!!!