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Many animals are actually over-engineered. Just copy only what’s necessary.

Posted by: adonis49 on: October 23, 2017

Many animals are actually over-engineered. Just copy only what’s necessary.

Insects and animals have evolved some amazing skills — but, as Robert Full notes, many animals are actually over-engineered. The trick is to copy only what’s necessary. He shows how human engineers can learn from animals’ tricks.

This talk was presented at an official TED conference, and was featured by our editors on the home page.

Robert Full · Biologist. studies cockroach legs and gecko feet. His research is helping build tomorrow’s robots, based on evolution’s ancient engineering.

00:13

Contrary to calculations made by some engineers, bees can fly, dolphins can swim, and geckos can even climb up the smoothest surfaces.

Now, what I want to do is to try to allow each of you to experience the thrill of revealing nature’s design.

I want to try to share just a little bit of that with you in this presentation. The challenge of looking at nature’s designs — and I’ll tell you the way that we perceive it, and the way we’ve used it.

The challenge is to answer this question: what permits this extraordinary performance of animals that allows them basically to go anywhere? And if we could figure that out, how can we implement those designs?

many biologists will tell engineers, and others, organisms have millions of years to get it right; they’re spectacular; they can do everything wonderfully well.

the answer is bio-mimicry: just copy nature directly.

We know from working on animals that the truth is that’s exactly what you don’t want to do — because evolution works on the just-good-enough principle, not on a perfecting principle.

And the constraints in building any organism, when you look at it, are really severe. Natural technologies have incredible constraints. Think about it.

If you were an engineer and I told you that you had to build an automobile, but it had to start off to be this big, then it had to grow to be full size and had to work every step along the way.

Or think about the fact that if you build an automobile, I’ll tell you that you also — inside it — have to put a factory that allows you to make another automobile.

And you can absolutely never, absolutely never, because of history and the inherited plan, start with a clean slate.

So, organisms have this important history. Really evolution works more like a tinkerer than an engineer.

And this is really important when you begin to look at animals. Instead, we believe you need to be inspired by biology. You need to discover the general principles of nature, and then use these analogies when they’re advantageous.

It is a real challenge to do this, because animals,when you start to really look inside them — how they work — appear hopelessly complex. There’s no detailed history of the design plans, you can’t go look it up anywhere. They have way too many motions for their joints, too many muscles. Even the simplest animal we think of, something like an insect, and they have more neurons and connections than you can imagine.

How can you make sense of this? Well, we believed — and we hypothesized — that one way animals could work simply, is if the control of their movements tended to be built into their bodies themselves.

What we discovered was that two-, four-, six- and eight-legged animals all produce the same forces on the ground when they move. They all work like this kangaroo, they bounce. And they can be modeled by a spring-mass system that we call the spring mass system because we’re bio-mechanists. It’s actually a pogo stick.

They all produce the pattern of a pogo stick. How is that true? Well, a human, one of your legs works like two legs of a trotting dog, or works like three legs, together as one, of a trotting insect, or four legs as one of a trotting crab. And then they alternate in their propulsion, but the patterns are all the same.

Almost every organism we’ve looked at this way — you’ll see next week, I’ll give you a hint, there’ll be an article coming out that says that really big things like T. Rex probably couldn’t do this, but you’ll see that next week.

what’s interesting is the animals, then bounce along the vertical plane this way, and in our collaborations with Pixar, in “A Bug’s Life,” we discussed the bipedal nature of the characters of the ants. And we told them, of course, they move in another plane as well. And they asked us this question.

They say, “Why model just in the sagital plane or the vertical plane, when you’re telling us these animals are moving in the horizontal plane?”

This is a good question. Nobody in biology ever modeled it this way. We took their advice and we modeled the animals moving in the horizontal plane as well. We took their three legs, we collapsed them down as one. We got some of the best mathematicians in the world from Princeton to work on this problem.

And we were able to create a model where animals are not only bouncing up and down, but they’re also bouncing side to side at the same time. And many organisms fit this kind of pattern.

Now, why is this important to have this model? Because it’s very interesting. When you take this model and you perturb it, you give it a push, as it bumps into something, it self-stabilizes, with no brain or no reflexes, just by the structure alone. It’s a beautiful model. Let’s look at the mathematics.

The animals, when you look at them running, appear to be self-stabilizing like this, using basically springy legs. That is, the legs can do computations on their own; the control algorithms, in a sense, are embedded in the form of the animal itself.

Why haven’t we been more inspired by nature and these kinds of discoveries? Well, I would argue that human technologies are really different from natural technologies, at least they have been so far.

Think about the typical kind of robot that you see.Human technologies have tended to be large, flat, with right angles, stiff, made of metal. They have rolling devices and axles. There are very few motors, very few sensors.

Whereas nature tends to be small, and curved, and it bends and twists, and has legs instead, and appendages, and has many muscles and many sensors. So it’s a very different design.

However, what’s changing, what’s really exciting is that as human technology takes on more of the characteristics of nature, then nature really can become a much more useful teacher.

And here’s one example that’s really exciting. This is a collaboration we have with Stanford. And they developed this new technique, called Shape Deposition Manufacturing.

It’s a technique where they can mix materials together and mold any shape that they like, and put in the material properties. They can embed sensors and actuators right in the form itself.

For example, here’s a leg: the clear part is stiff, the white part is compliant, and you don’t need any axles there or anything. It just bends by itself beautifully. So, you can put those properties in.

It inspired them to show off this design by producing a little robot they named Sprawl. Our work has also inspired another robot, a biologically inspired bouncing robot, from the University of Michigan and McGill named RHex, for robot hexapod, and this one’s autonomous.

Let’s go to the video, and let me show you some of these animals moving and then some of the simple robots that have been inspired by our discoveries. Here’s what some of you did this morning, although you did it outside, not on a treadmill. Here’s what we do.

This is a death’s head cockroach. This is an American cockroach you think you don’t have in your kitchen. This is an eight-legged scorpion, six-legged ant, forty-four-legged centipede. Now, I said all these animals are sort of working like pogo sticks — they’re bouncing along as they move.