The problem is that you can’t comfortably anchor it to the body in a way that lets you put so much force on it. Putting weight on an amputation stump hurts.
Exoskeletons, on the other hand, are in development. They have working ones, but they don’t work well enough for general use yet. And there’s the problem of safety: you need to make sure you don’t exceed the limits of the user.
I’ve seen some pretty gnarly prosthetics that attach to nerves and are manipulated just like your real limbs (not as dexterous tho) and they could make you stronger than before but they tend to limit the actuation limits so you don’t accidentally squeeze too hard. You are also still limited by your meat that it attaches to. Have you ever seen the OG Ghost in the Shell? Remember the end when the Major is breaking into that tank? You wouldn’t want to rip your arms off again trying to lift something your flesh and bone shoulders, back and legs couldn’t handle.
Yeah, regardless of how ‘strong’ a prosthetic may be, biomechanics is still very much a limiting factor.
On the other metallic hand: I wouldn’t want someone with any kind of posthesis to punch me with it.
We’re not really close to the point where any prosthetic is an upgrade on any human limb. Prosthetics you can control with your mind do exist, but are severely limited compared to human limbs. I’ve yet to see any prosthetic that’s stronger than a human limb.
There are two big limitations to consider:
- Even if you could attach a more powerful machine to a person, the attachment point is always going to be the weak point.
- How do you power it? Battery technology just isn’t there yet. You’d be lucky if you got 2hrs of super arm followed by several hours of charging.
I’m no expert, but I do have an interest in prosthetics and have been following the news and have seen lots of conversations that have no solutions for those two problems.
the main benefits from prosthetics are usually due to properties that the prosthetic have that a normal limb wouldn’t have (or vice versa) - like specialized prosthetic limbs for rock climbing
still, I would expect most people would be able to use a tool in lieu of a prosthetic … still, the absence of a limb might be advantageous in some situations (even if obviously a downside in others).
This won’t be a full answer to your question, as these aren’t exactly off-the-shelf prosthetic devices, but you should really check out Ian Davis on YouTube…
If I remember correctly, I think another major hurdle is the feedback loop part (prosthetic inputs to neural connections). We have some relative understanding of having machines to act in how we intend, but without that loop, still leads to a lot of errors. I don’t mean full simulation of the sensorium to mimic having your arm back, but the minimal amount necessary for fluid movement without conscious visual monitoring.
