Sunday, 20 September 2009

Walking machines

The world of mechanics and robotics proved to contain some interesting analogues and even inspiration for speculative biological creations. That worked for flying animals, both of the heavier than air and of the lighter than air variety. No wonder that the thought came up that walking and other terrestrial modes of transportation could undergo the same treatment.

So, are there interesting mechanical contraptions out there that deserve to be 'biologified'? (I just invented that word but checked it on Google to be certain. Unfortunately, I was not the first: 'biologify' has 3 hits and its derived noun 'biologification' already has 91. Oh well...).

Well, the result of my search is a bit less dramatic than held for the flying animals, but there are some intriguing inventions out there. If you type in words such as 'walking machines' or 'robot insect' into Google, you will find many hits. Most concern toys with usually a high number of legs, of which only a few are lifted at a time. Most are not at all sophisticated in the sense of having integrated sensory and motor systems with balancing reflexes. No neural control at all, sadly. Instead there is just a motor and some mechanical bits and pieces that turn a rotary motion into steps. If you look at them, you realise how complicated and advanced biological walking really is. Still, that does not mean that people cannot have fun with these machines, and watching them is good fun as well. Just have a look at the following clunker:

I found it on YouTube, where it is labelled as a walking machine at "Burning Man '07" You can see that there are at least four legs on the ground at any time, so no delicate balancing tricks here. There doesn't seem to be much in the way of a suspension either, so it might pay to bring a soft cushion.

A more advanced machine is the so-called 'walking tractor'. From what I read, it was a design by a Finnish company meant for the logging industry, but the company apparently no longer exists. You can see they followed the double tripod design, in which three legs are always on the ground. This one apparently had advanced computerised controls. Here it comes:

A walker that really is beginning to look like an animal is the 'Big Dog' by Boston Dynamics. It is supposed to help soldiers cross difficult terrain. A very convincing demonstration occurs halfway in the video: someone kicks it, and it obviously has the reflexes to deal with that. If it steps in a hole, it can even deal with that without falling too. It is lengthy, but worthwhile:

I found it extremely impressive. Well, for a machine, that is. It is not impressive for an animal, which shows how much cybernetics still have to catch up...

None of these machines provide new inspiration in the sense of something that biology hasn't come up with yet. Surely there is something of interste for those who do speculative biology? Yes, there is: in the first place, machines such as the clunker shown above do hold some interest, as their legs work as 'pantographs': there is a system of bars linked together with movable joints, and no biological leg works like that. I will keep that subject for another entry, and that will also deal with Theo Jansens 'standbeesten'.

I will close with something for which I do not think there is a biological analogue, and I rather doubt the design idea lends itself will for biologification. It is a tripod walk. You will probably be disappointed know, seeing that tripod walkers go back as far as HG Wells in 'The war of the worlds'. (By the way, walking with odd numbers of legs might also merit a blog entry one day: there are pentapod walkers on Furaha, not to mention Epona!) But the design here has a twist. Almost literally, in fact. Its home page is here It is very creative and very crazy at the same time, so I cannot help but like it! Does anyone think it makes sense for an animal to move like this?


Pavel Volkov said...

"It's nothing new under the moon" - as proverb says. In XIX century Russian inventor Paphnuty Chebyshev made walking mashine. Here it is 3D reconstruction of it:

Pavel Volkov said...

Here it is better link:

Pavel Volkov said...
movie here

Sigmund Nastrazzurro said...

Hi Pavel,

Thanks for the links. That is an intriguing machine, and the animations are excellent!

Anonymous said...

I once came up with a tripod design for a speculative biology species. It supported the majority of its weight on its front two legs, and had a third in the back. When it ran, it used this third leg to push itself forward, leading to its movement resembling a galloping mammal, or maybe a weird rabbit. When it walked, the third leg only took a half-step for each full step of the forelimb, allowing the hind limb to keep up.

Birdy said...

Wow! Uncanny valley much? The Big Dog- the buzzing noise doesn't help- and the tripod especially.
Interesting, but creepy.

Sigmund Nastrazzurro said...

Dear Anonymous,
Hold on: I will be getting back to that subject...

dear Birdy,
Ahem; you've lost me. I had no idea of what 'uncanny valley much' meanst I just typed that into Google, and found something that probably indicated what you were alluding to.

And there I was, thinking that English is so much more easy than almost any other language. Would you care to elaborate?

Uncephalized said...

SN: the "_____ much?" idiom is an American/Internet sarcastic shorthand for "this thing I am describing has the specified characteristic '_____' in plentiful quantity, wouldn't you agree?"

So Birdy is saying s/he finds the robots creepy because of their lifelike movements juxtaposed with their otherwise obvious artificiality/alienness.

Y'know, in case you were still curious after 4+ years. :-D

Loving this blog! I just stumbed across it doing research for a science fiction series I'm working on. Currently reading through from the first post.

I have several thoughts regarding your series on walking tentacles/extensile muscles, as well as on the possible physics and ecologies of ballontypes in various atmospheric conditions (I'm a mechanical engineer with an amature passion for evolution and biology, so this stuff is right up my alley). But I'll save those for when I've caught up on your archive...

Sigmund Nastrazzurro said...

Hello Uncephalized, and welcome. As far as Birdy's comment was concerned, I was not surprised by the 'much' part of the comment -although I had not realised it was specifically American-, but by 'uncanny valley', which I had never heard before or since.

It is probably the first time an engineer took an interest in my blog, so I look forward to your comments. I might have a question or two for you as well!