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They were building a very ambitious Biped Walker out of wood a while back but it seems to have been scrapped now.

From TFA:

Scientists have developed an ultra-light limb that they claim can mimic the movement in a real hand better than any currently available.

Not to detract from the good work these guys are doing to restore mobility to the disabled, but... They can claim all they want about "any currently available," doesn't make it any less b*llsh*t. The Shadow Dextrous Hand has been available since 2002 and has way more degrees of freedom (they have all five DoF on the thumb for starters, not just two). The only things these guys have got going for them is that theirs is powered electrically (Shadow's is pneumatic) and they have a bio-interface to trigger their electronics from muscle contractions.

A far better analog to the human hand is located here. The robotics folks over at Shadow really know what they're doing (check the videos). As anyone who checks the Shadow site will see, TFA's "clever artificial hand" does not win the prize for "the first artificially-made opposable thumb." Interesting nevertheless..if only we could see some realworld applications..

There are plenty of robot hands that are far better than this. e.g. #1 e.g. #2.

http://www.shadow.org.uk/index.shtml ? Of course this thing is pneumatic and not gonna work in deep space out of the box.

No problem on the extra hands...

Like I said before, some of the DoF are rather obtuse or tend to run 'coupled'. I know several people who can totally independantly control the final joint on their fingers, though. Even most 'normal' people can if they do this:

1) hold fingers out straight
2) bend at 'middle' joint, trying to keep the 'final' (third) joint straight
3) once there, try to bend the final joint (should be easy enough, since that's the normal 'grip' position)
4) play with it a bit and you should be able to demonstrate some rudimentary control over those last joints

Okay, now for the thumb....

Hooboy. ;-)

The Middle2 they refer to is a 'tilting' motion, similar to the one you mentioned between fingers. Make a gesture like you're holding a guitar neck. Now hold on to the base of your thumb, HARD, and try to move the rest of your thumb over as if you were operating a click pen. Move back and forth and you'll notice that there's about a 10 or 15 degree rotation orthogonal to the primary bending direction. In this image, there's a metal post through the middle joint of the thumb. That's the axis of rotation for this effect.

Keep in mind that, unlike the fingers, the thumb's base isn't fixed to the wrist, but has 2 DoF all of it's own.

So, we have one bend for the 'last' (distal) joint, one bend and a perpendicular tilt for the 'middle' (medial) joint, and two more rotational components for the 'base' (proximal): a roll to point your thumb, and a bend to open/close the whole thumb arrangement. That's 5 DoF. *phew*

Anyway, I'll reiterate: most of these DoFs are essentially useless for UI purposes. 10 per hand is plenty. The face has tons more, the shoulders have 5 each (vertical and horizontal translation, rotate out, rotate up and rotate the whole arm), etcetera. Humans have a ridiculously large number of ways to move. All I want is to tap into 16 or so of them at a time, rather than 2 or 6 continuous (mouse and SpaceOrb, respectively) or 108 discrete (keyboard) axes....

Of course, dancers, sculpters, musicians and so on will always want more, but they don't read SlashDot, do they?! =D

I ended up buying a metal lathe and high temp welding gear after years of frustration trying to find/adapt parts. Metal lathes can be had (for very small parts) for around $150, see the Clisby Lathe. It's easy to spend more than that and you should always count on spending 150% of the price of the machine on tooling for it.

Casting small parts is also feasible for some solutions, check out the small parts casting info at Micro Mark. It's conceivable that you could use Lego parts as the model for parts you cast in metal (zinc and aluminum are easy but there are lower temp alternatives.)

The really cool anatomical robot stuff is being done with Air Muscles which can be home brewed with a little ingenuity.

http://www.shadow.org.uk/movies/HandA-beer.mpeg

The Air Muscle consists of a rubber tube covered in tough plastic netting which shortens in length like a human muscle when inflated with compressed air at low pressure.

From the company site


* Stock x86 PC running Debian GNU/Linux with RTAI real-time system.
* Shadow's own GPL'd robot code will be shipped, permitting initial setup and evaluations. PC will have CAN interface provided.

The "Air Muscles" are a bit more complex, since they need a supply of compressed air, and all the associated support mechanisms (relief valves, air lines, control valves, etc), but you can make them from dirt cheap materials (the one I built cost me about $1.00, though I had to buy more materials than I ended up using -- however, I can still use those extra materials to make more muscles).

The Air muscles are also a bit easier to scale. The Shadow Robot Co. people claim that four of their larger air muscles can provide enough pull to lift a car. They also have a Usenet post that makes a lot of interesting claims about possibilities for the air muscles. Of course, these claims were made six years ago, and I personally haven't seen the air muscles being used in any of these applications, so there may be some complications that the Shadow Robot people aren't telling us about.

Here is a good site that gives a good reference on what are, and how they work.

The are electric linear actuaters as well, that work on a telescoping lead screw rod type system, as well as solenoid based, and SMA (shape memory alloy) actuators - however, none of these have as fast response times, and waste more power.

Even air muscles aren't perfect, but they are interesting...

But I've been downloading trans-oceanic quicktimes for the past couple of hours (at 28.8) and I still think it's a hoax.

Depictions of robots in sci-fi movies have always had the problem that they skip over the 'intermediate forms' between obviously-not-human and much-too-realistically human-with-a-few-small-flaws. And as far as I can see Honda's materials commit the same sin-- where are the intermediate forms???

A real example of an intermediate form

If you see a demo that in every detail resembles a person crouched in a special suit... what does Occam's razor say you should conclude?

Why did they need to give it a humanoid torso and arms? Why do these also move exactly like the human versions? Why is the head concealed in a visor, if not to give their actor a way to look around? Why do the P3 quicktimes show only the cliched, anonymous box-with-blinking-lights inside, instead of showing off the real high-tech in the legs?

PROVE ME WRONG, PLEASE!

My page of robotics links if you're interested.

Nitinol is cute, but very limited. It needs a huge power to generate a small force - most is wasted in heat.

Mondotronics have a cute project book and kit for Nitinol, which is a splendid birthday present for any geek larvae you might know. Milford Instruments sell it in the UK.

If you want a more workable muscle for small robots, look at the Air Muscle from Shadow Robots. These are interesting because they generate a pull action from air pressure, yet in a small package.