BEYOND COMPUTATION: A TALK WITH RODNEY BROOKS

If we—or more probably, other people—are successful at this, and can get to a real understanding of how all of these different pathways inside a living system interact to create a living system, then we'll have a new level of technology that can be built on top of that. We will in a principled way then be able to manipulate biological material in the way that we've learned in the last couple of hundred years to manipulate steel and then silicon. In 50 years our technological infrastructure and our bodies may be quite indistinguishable in that they'll be the same sort of processes.

I have several interesting robotics projects underway. One of the robots I must say was inspired by Bill Joy, probably to his dismay. We have a robot now that wanders around the corridors, finds electrical outlets, and plugs itself in. The next step is to make it hide during the day and come out at night and plug itself in. I'd like to build a robot vermin. Once I started talking about this, someone told me about a science fiction story from the '50s or '60s about a similar creature—The Beast Mark 3, or 4—which I like quite a lot. In the story the robot squeals when you pick it up and runs away. It doesn't have an off-switch, so the only way to get rid of it is to take a hammer to the thing, or lock it in a room where there are no outlets and let it starve to death. I'm trying to build some robots like that as thought-provoking pieces—and just because Bill Joy was afraid of them.

We're also trying to build self-reproducing robots. We've been doing experiments with Fischer Technik and Lego. We're trying to build a robot out of Lego which can put together a copy of itself with Lego pieces. Obviously you need motors and some little computational units, but the big question is to determine what the fixed points in mechanical space are to create objects that can manipulate components of themselves and construct themselves. There is a deep mathematical question to get at there, and for now we're using these off-the-shelf technologies to explore that. Ultimately we expect we're going to get to some other generalized set of components which have lots and lots of ways of cooperatively being put together, and hope that we can get them to be able to manipulate themselves. You can do this computationally in simulation very easily, but in the real world the mechanical properties matter. What is that self-reflective point of mechanical systems? Biomolecules as a system have gotten together and are able to do that.

We've also been looking at how things grow. We, and biological systems, grow from simple to more complex. How do the mechanics of that growth happen? How does rigidity come out of fairly sloppy materials? To address these questions we've been looking at tensegrity structures. On the computational side, I'm trying to build an interesting chemistry which is related to physics and has a structure where you get interesting combinatorics out of simple components in a physical simulation, so that properties of living systems can arise through spontaneous self-organization. The question here is: What sorts of influences do you need on the outside? In the pre-biotic soup on Earth you had tides, which were very important for sorting. You had regular thunderstorms every three or four days which served as very regular sorting operations, and then we had the day and night cycle—heating and cooling. With this thermodynamic washing through of chemicals, it may be that some clays attached themselves to start self-organizations, but you had to get from crystal to this other sort of organization. What are the key properties of chemistry which can let that arise? What's the simplest chemistry you can have in which that self-organization will arise? What is the relationship between the combinatorics and the sorts of self-organizations that can arise? Obviously our chemistry let that arise. We are creating computational systems and exploring that space.

My company, iRobot, has been pushing in a bunch of different areas. There's been a heightened interest in military robots, especially since September 11. By September 12 we had some of our robots down at Ground Zero in New York trying to help look for survivors under the rubble. There's been an increase in interest in robots that can do search and rescue, in robots that can find mines, and in portable robots that can do reconnaissance. These would be effective when small groups, like the special forces we've seen in Afghanistan, go in somewhere and they don't necessarily want to stick their heads up to go look inside a place. They can send the robot in to do that.