- My name is Hod Lipson. And I am a professor of engineering here at Columbia University. One of the big trends in robotics now is moving away from these mechanical hard rigid robots to soft robots. The ones that are made of compliant materials, soft materials that are much more sort of life-like and have a lot of advantages. But one of the key challenges to making soft robots is how do you make a soft motor, a soft activator, something like a muscle that can expand and contract and move that will be made entirely out of soft material. So what we've developed here in the lab is a new kind of synthetic muscle. It's material that's composed of silicone and ethanol, combination of 80 percent silicone 20 percent ethanol. You mix these two things together, and you heat it up and it expands almost nine times its volume. That's a very, sort of, convenient fore factor allows this muscle to expand and contract and can be used for lots of soft robotics applications. So the way this muscle works is that you have these very small bubbles of ethanol trapped in the silicone matrix. These microscopic bubbles are liquid. When you heat the material up, these tiny bubbles, essentially liquid, evaporate and form into gas. So they associate lots of these small pistons, if you like, that expand. Once you stop passing current, or heating this material, they condense and shrink back into liquid. So you have this basically phase transition from liquid to gas back to liquid, and that allows the material to expand and contract, that produces enormous forces and strength for its weight. In fact, 15 times more than natural muscle. And yet it's a very simple material that you can sort of make even at home. We're excited to see how it's gonna be used. This particular material is very easy to 3D print, to cast, to form, into any shape you want. So you can really, unlike let's say a motor that you have to pick and choose from standard sizes, you can't take a motor and cut it into half and place it in a tight space. This kind of material you can really shape and cast, 3D print into any shape that you want. So it's a... Now the question is, how are we going to use it? We've used it in a couple of different ways. We've created a robotic gripper. We've put a pair of them in sort of antagonistic coupling like we have in the human arm. We've used it to lift weights and things like that. But really, there's sort of no end to how it can be used. We don't know how it's going to be used. All we know is that it's going to unleash a lot of potential designs for soft muscle that were not possible before. And we'll see where it goes. One of the biggest challenges for robotics today that most people aren't aware of, I think, is something we call the body problem. And that's the idea that we see our divisiontologists moving forward by leaps and bounds. Every day you hear about a new accomplishment that AI can do, but when it comes to physical robots, we're in the dark ages. Digital manufactured technologies and 3D printer are really opening the door to creating new kinds of robots. When you look at Hollywood, it's always about these sort of robots that are made of, you know, hard components that are bolted together. But the way things are moving increasingly will probably move to more organic looking robots that are made of lots of different materials that are coal fabricated at the same time. And they're very free form function. We're seeing this more and more, even if you look at things like drones. A lot of the more novel research in drones involves 3D printed parts that are much more you know, have a better weight to strength ratio and so on. So I think we'll see more and more of that kind of fabrication. These fabrications qualities, these new materials, permeate lots of engineering fields from aerospace to robotics. I think that robotics in general has been held back, if you like, by the fact that we can only use standard size motors. We can only build limbs that use conventional motors that have certain requirements, and we couldn't shape motors into any full factor that we want. With this kind of technology and sort of derivatives of it, it really frees us up to make limbs that have arbitrary shapes, muscles that conform to the limb they're in. Very much like biology does. Every one of our muscles looks different, is optimized to particular tasks it needs to do the particular context it's in. And that has to be the case for conventional robotics up until now. So I think we're about to see this sort of change in the shape and size of robots because we're sort of unleashing ourselves from this very strict constraint that we had to deal with for many years.