From Honda: the Asimo was the "first" robot to walk like a human, and now the same technology is helping people walk on their own. I wonder how long it'll take Honda to realise this into robotic leg replacements.

The real problem is that robtic legs are difficult. Robots that actual walk are exceedingly difficult because the human leg is actually fairly impressive. Even once you get past that, the bigger problem is the DNI required to make it into a cyberleg. DNI is currently very very limited, the number of people with it is likely under a dozen, and the control ability is fairly limited.

So yeah, getting closer, but some notable limits still need dealing with.

Power is also a big concern.

Modern batteries are getting better all the time but the fact remains that it's difficult to cram a lot of battery power into something that's supposed to be light and portable.

But if we could use the power generated by our own system. Some kind of slowburning micro-generators which use up our sugar and stuff... thousands/millions of them.

That is significantly more complicated than you might think.

First there is the issue of building a generator that small, then there is the issue of producing thousands/millions of them cheaply, then there is getting that many things into a human body, then there is the issue of making a generator that can actually run on products from the human body, then there is making a generator that can interact well with the human body.

No, power is going to be another huge limiting issue on any sort of cyberlimbs. I'd imagine that initial versions will force people to carry batteries, much like a powered wheel chair has a battery pack on the back.

They're making some inroads on the DNI, from the looks of an article link that got posted here yesterday. As for the power source...I wonder how much output a pacemaker could give.

Doesn't a pacemaker run on a battery too? I don't see how that would help any.

Yes, that's the point. I'm curious as to its output since those things are typically nuclear-powered for longevity's sake. If the battery's enough to run the limb instead of the heart - hey, power problem's solved.

Umm... yeah, sure they are.

Actually they are powered by a fairly normal lithium ion battery (the same thing in your iPod).

They used to. Cut the condescension.

They've never ever been nuclear powered.

They developed isotope pacemakers in the 60's, and stopped when the Lithiums were developed in '71.

Edit: We can go back and forth on it until someone's got their moral victory, but that's not the point. If the isotope battery or the lithium one has the power for it, I don't care which, you can power the limb with it. That is the point.

Isotope does not mean nuclear powered. But that aside, my point is that it is a lithium battery, which can power your iPod for what? Several hours? (I really don't know, I don't own one) My lithium battery for my laptop is about 8"x3"x.5" and can power my computer for about two hours.

This is tens of times larger than a pacemaker battery, and I would think that my computer uses less energy than running a cyberlimb would. At least a leg while standing/walking. I suppose a leg wouldn't use much energy while sitting down, but when actively being used, I think the energy expenditure would be fairly great. This seems to indicate that a pacemaker wouldn't be able to provide nearly enough power to run a cyberlimb. I do however think that leaves a small battery pack as an option. If you have something a few times thicker than my laptop battery, I'd imagine you could get a full day's use out of a cyberlimb before it needs recharging unless you're running a marathon or something. Now, 8"x3"x2" isn't all that big, and in the case of a leg, might well be able to fit inside the leg itself. So then you'd just need to remember to plug in your leg each night before you go to bed.

I suppose basic energy isn't such a problem, but energy on the level of SR (cyberlimbs have no issues with power at all, and can run constantly for days on end without the need for power)

I'm not sure it would be processing as much as a laptop does, though. That should extend the battery life on it, and you'd be looking for - at most - 24 hours before a charge, likely more like 16 hours. Make the battery pack removable and in a holster on or around the outer thigh so it's not frying your other leg or your hips, and you can swap the pack out for a fresh one when you get home from work. Figure ten hours tops, and I don't think the majority of people would be using it for constant activity for that ten hour stretch.

Pacemakers don't use very much power at all. Its just simulating a nervous signal to the heart; nervous potential is on the order of .1 volt. Amperage is similarly very low. They adapt pacemakers for BRAIN stimulation, so no, your not talking cyber-limb power here, not without scaling up the battery- in which case you get what is effectively a high quality laptop (or EV racing) battery.

And yeah, Shadowrun batteries are obviously absurdly better than ours. There's freaking hand held portable weaponized lasers and radio jammers, both of which require fair sized generators for power these days.

Cyberlimb users probably wouldn't ever have to "plug in", either. They'd just draw power the same way a grid-guide vehicle (and probably most com's) do. They might upgrade the system they have in their bedroom compared to what a normal user has, but I doubt anybody bothers with cords and wall warts in Shadowrun. That makes battery life much less a concern, at least in urban settings.

I'm curious to know the current battery life of the energy source for the current exoskeletal version of the future cyberlimb. Maybe that would give us hints.

True, it maybe isn't computing much, but my laptop isn't moving 200 lbs of weight either. I figure the energy required to move that much weight is alot more than required for computing. I don't know for sure of course, but basic physics tells me the movement requires quite a bit of energy.

On that train of thought, one wonders what a human body could power if it were plugged in. What kind of output is burning 2,000 calories a day?

Human body generates roughly 81 watts. Although I suspect we use most of that.
Briskly walkign we rev up to over 400 watts.

Lets see, 2000 calories a day is 8373.6 kJ of energy.

A lithium-ion battery has 460 kJ/kg, which means the battery to last half a day (12 hours) would weigh 10 kilos (22 lbs). An interesting point is that it would also be about 5 liters in size, which is bigger than a gallon of milk.

Of course all that energy isn't going towards your legs, but a good portion is, so I'd say a good 7 kilo/4 liter battery would be required to operate both legs for 12 hours or so, which seems like a reasonable operation time. That is a fair chunk of added size/weight though. Might be able to squeeze it into the legs themselves.

Titanium should save weight on construction, and you can run the battery pack as the thigh or even the lower leg, depending on heat issues. I don't think the first gen cyberlimbs would be as large as a regular one - I mean thinner, less flesh and such for muscles and fat insulation. The battery would replace that bulk and could conceivably 'sleep' when the leg isn't being used, such as when you're seated at a desk. A 12-hour battery would be fine, though a 10-hour may save some size. Length of time charging would also be an issue.

Lithium Ion batteries recharge fairly quickly. I'm sure an 8 hour night would be enough to recharge the leg.

There you have it, then. Two ten-hour batteries per leg, and one can wall-charge while the other is active. If weight/space isn't an issue, then 12-hour batteries will handle it.

If it was powered armor - hope we have miniaturized reactors by then.

Isn't another hurdle in the way of cyberlimbs the fact that any sort of transdermal bone anchoring is a flashing neon sign saying "INFECT ME HERE" due to the fact that skin won't bond with metal, outside of still-experimental procedures that haven't been tested on humans?

I don't think that is actually such a bit issue. They have datajacks (kinda) now and those don't seem to be particularly susceptible to infection.

Sounds resonable

Umm, why not use some ideas from Nikola Tesla and simply build in ambient power accumulators that recharge the batteries (or simply power the limb directly) from the amount of energy that is being broadcast into the environment? Especially in the age of the Wireless world.

Besides it not working?

I recall Mythbusters attempting something like this and it required 150 feet of stretched out wire to get about the equivalent of a watch battery.

It does work, but it certainly doesn't provide enough power for something like cybernetic limbs. There was a 100' string of LED christmas lights on the wall outside my bedroom a couple years back that kept glowing very faintly even while unplugged, just drawing off of the EMI generated by all my electronics.

You... haven't been getting any headaches while in that room, have you?





-karma

Right, it does work, but only if you have a long spread out wire. You had 100' (likely more because I think a string of LED lights goes both ways with the wire) and had enough power to maybe fully power an LED or two. So yes, it works but it isn't something that could be applied usefully to something like this.

I suppose I shouldn't have said 'doesn't work'. It just isn't useful.

Exactly my point. It works, it's just not useful for anything beyond something like very dim safety lighting - which, in all honesty, can be powered by nearly anything you can pull a bit of current from.


Nothin' a 440mg dose of naproxen sodium couldn't fix. Better living through chemistry!