Dennis Hong: My 7 species of robot

138,128 views ・ 2010-04-07

TED


Please double-click on the English subtitles below to play the video.

00:16
So the first robot to talk about is called STriDER.
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It stands for Self-excited Tripedal Dynamic Experimental Robot.
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It's a robot that has three legs, which is inspired by nature.
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But have you seen anything in nature, an animal that has three legs?
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Probably not. So why do I call this a biologically inspired robot?
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How would it work?
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But before that, let's look at pop culture.
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So, you know H.G. Wells's "War of the Worlds," novel and movie.
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And what you see over here is a very popular video game,
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and in this fiction, they describe these alien creatures and robots
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that have three legs that terrorize Earth.
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But my robot, STriDER, does not move like this.
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This is an actual dynamic simulation animation.
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I'm going to show you how the robot works.
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It flips its body 180 degrees
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and it swings its leg between the two legs
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and catches the fall.
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So that's how it walks.
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But when you look at us human beings, bipedal walking,
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what you're doing is,
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you're not really using muscle to lift your leg and walk like a robot.
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What you're doing is, you swing your leg and catch the fall,
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stand up again, swing your leg and catch the fall.
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You're using your built-in dynamics, the physics of your body,
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just like a pendulum.
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We call that the concept of passive dynamic locomotion.
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What you're doing is, when you stand up,
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potential energy to kinetic energy,
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potential energy to kinetic energy.
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It's a constantly falling process.
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So even though there is nothing in nature that looks like this,
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really, we're inspired by biology and applying the principles of walking
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to this robot.
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Thus, it's a biologically inspired robot.
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What you see here, this is what we want to do next.
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We want to fold up the legs and shoot it up for long-range motion.
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And it deploys legs -- it looks almost like "Star Wars" --
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so when it lands, it absorbs the shock and starts walking.
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What you see over here, this yellow thing, this is not a death ray.
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(Laughter)
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This is just to show you
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that if you have cameras or different types of sensors,
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because it's 1.8 meters tall,
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you can see over obstacles like bushes and those kinds of things.
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So we have two prototypes.
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The first version, in the back, that's STriDER I.
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The one in front, the smaller, is STriDER II.
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The problem we had with STriDER I is, it was just too heavy in the body.
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We had so many motors aligning the joints
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and those kinds of things.
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So we decided to synthesize a mechanical mechanism
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so we could get rid of all the motors, and with a single motor,
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we can coordinate all the motions.
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It's a mechanical solution to a problem, instead of using mechatronics.
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So with this, now the top body is lighted up; it's walking in our lab.
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This was the very first successful step.
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It's still not perfected, its coffee falls down,
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so we still have a lot of work to do.
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The second robot I want to talk about is called IMPASS.
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It stands for Intelligent Mobility Platform with Actuated Spoke System.
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It's a wheel-leg hybrid robot.
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So think of a rimless wheel or a spoke wheel,
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but the spokes individually move in and out of the hub;
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so, it's a wheel-leg hybrid.
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We're literally reinventing the wheel here.
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Let me demonstrate how it works.
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So in this video we're using an approach called the reactive approach.
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Just simply using the tactile sensors on the feet,
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it's trying to walk over a changing terrain,
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a soft terrain where it pushes down and changes.
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And just by the tactile information,
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it successfully crosses over these types of terrains.
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But, when it encounters a very extreme terrain --
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in this case, this obstacle is more than three times the height
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of the robot --
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then it switches to a deliberate mode,
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where it uses a laser range finder and camera systems
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to identify the obstacle and the size.
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And it carefully plans the motion of the spokes
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and coordinates it so it can show this very impressive mobility.
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You probably haven't seen anything like this out there.
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This is a very high-mobility robot that we developed called IMPASS.
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Ah, isn't that cool?
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When you drive your car,
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when you steer your car, you use a method called Ackermann steering.
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The front wheels rotate like this.
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For most small-wheeled robots,
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they use a method called differential steering
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where the left and right wheel turn the opposite direction.
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For IMPASS, we can do many, many different types of motion.
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For example, in this case,
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even though the left and right wheels are connected
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with a single axle rotating at the same angle of velocity,
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we simply change the length of the spoke, it affects the diameter,
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then can turn to the left and to the right.
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These are just some examples of the neat things we can do with IMPASS.
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This robot is called CLIMBeR:
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Cable-suspended Limbed Intelligent Matching Behavior Robot.
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I've been talking to a lot of NASA JPL scientists --
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at JPL, they are famous for the Mars rovers --
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and the scientists, geologists always tell me
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that the real interesting science, the science-rich sites,
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are always at the cliffs.
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But the current rovers cannot get there.
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So, inspired by that, we wanted to build a robot
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that can climb a structured cliff environment.
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So this is CLIMBeR.
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It has three legs.
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It's probably difficult to see, but it has a winch and a cable at the top.
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It tries to figure out the best place to put its foot.
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And then once it figures that out,
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in real time, it calculates the force distribution:
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how much force it needs to exert to the surface
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so it doesn't tip and doesn't slip.
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Once it stabilizes that, it lifts a foot,
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and then with the winch, it can climb up these kinds of cliffs.
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Also for search and rescue applications as well.
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Five years ago, I actually worked at NASA JPL
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during the summer as a faculty fellow.
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And they already had a six-legged robot called LEMUR.
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So this is actually based on that.
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This robot is called MARS:
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Multi-Appendage Robotic System.
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It's a hexapod robot.
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We developed our adaptive gait planner.
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We actually have a very interesting payload on there.
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The students like to have fun.
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And here you can see that it's walking over unstructured terrain.
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(Motor sound)
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It's trying to walk on the coastal terrain, a sandy area,
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but depending on the moisture content or the grain size of the sand,
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the foot's soil sinkage model changes, so it tries to adapt its gait
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to successfully cross over these kind of things.
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It also does some fun stuff.
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As you can imagine, we get so many visitors visiting our lab.
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So when the visitors come, MARS walks up to the computer,
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starts typing, "Hello, my name is MARS.
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Welcome to RoMeLa,
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the Robotics Mechanisms Laboratory at Virginia Tech."
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(Laughter)
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This robot is an amoeba robot.
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Now, we don't have enough time to go into technical details,
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I'll just show you some of the experiments.
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These are some of the early feasibility experiments.
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We store potential energy to the elastic skin to make it move,
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or use active tension cords to make it move forward and backward.
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It's called ChIMERA.
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We also have been working with some scientists and engineers
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from UPenn
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to come up with a chemically actuated version of this amoeba robot.
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We do something to something,
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and just like magic, it moves.
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"The Blob."
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This robot is a very recent project.
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It's called RAPHaEL:
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Robotic Air-Powered Hand with Elastic Ligaments.
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There are a lot of really neat, very good robotic hands
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out there on the market.
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The problem is, they're just too expensive --
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tens of thousands of dollars.
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So for prosthesis applications it's probably not too practical,
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because it's not affordable.
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We wanted to tackle this problem in a very different direction.
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Instead of using electrical motors, electromechanical actuators,
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we're using compressed air.
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We developed these novel actuators for the joints, so it's compliant.
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You can actually change the force,
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simply just changing the air pressure.
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And it can actually crush an empty soda can.
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It can pick up very delicate objects like a raw egg,
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or in this case, a lightbulb.
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The best part: it took only 200 dollars to make the first prototype.
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This robot is actually a family of snake robots
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that we call HyDRAS,
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Hyper Degrees-of-freedom Robotic Articulated Serpentine.
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This is a robot that can climb structures.
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This is a HyDRAS's arm.
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It's a 12-degrees-of-freedom robotic arm.
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But the cool part is the user interface.
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The cable over there, that's an optical fiber.
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This student, it's probably her first time using it,
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but she can articulate it in many different ways.
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So, for example, in Iraq, the war zone, there are roadside bombs.
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Currently, you send these remotely controlled vehicles that are armed.
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It takes really a lot of time and it's expensive to train the operator
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to operate this complex arm.
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In this case, it's very intuitive;
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this student, probably his first time using it,
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is doing very complex manipulation tasks,
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picking up objects and doing manipulation, just like that.
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Very intuitive.
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Now, this robot is currently our star robot.
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We actually have a fan club for the robot, DARwIn:
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Dynamic Anthropomorphic Robot with Intelligence.
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As you know, we're very interested in human walking,
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so we decided to build a small humanoid robot.
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This was in 2004; at that time,
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this was something really, really revolutionary.
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This was more of a feasibility study:
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What kind of motors should we use? Is it even possible?
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What kinds of controls should we do?
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This does not have any sensors, so it's an open-loop control.
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For those who probably know, if you don't have any sensors
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and there's any disturbances, you know what happens.
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(Laughter)
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Based on that success, the following year we did the proper mechanical design,
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starting from kinematics.
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And thus, DARwIn I was born in 2005.
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It stands up, it walks -- very impressive.
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However, still, as you can see, it has a cord, an umbilical cord.
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So we're still using an external power source
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and external computation.
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So in 2006, now it's really time to have fun.
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Let's give it intelligence.
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We give it all the computing power it needs:
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a 1.5 gigahertz Pentium M chip, two FireWire cameras,
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rate gyros, accelerometers, four forced sensors on the foot,
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lithium polymer batteries --
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and now DARwIn II is completely autonomous.
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It is not remote controlled. There's no tethers.
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It looks around, searches for the ball ... looks around, searches for the ball,
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and it tries to play a game of soccer autonomously -- artificial intelligence.
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Let's see how it does.
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This was our very first trial, and ...
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(Video) Spectators: Goal!
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Dennis Hong: There is actually a competition called RoboCup.
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I don't know how many of you have heard about RoboCup.
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It's an international autonomous robot soccer competition.
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And the actual goal of RoboCup is,
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by the year 2050,
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we want to have full-size, autonomous humanoid robots
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play soccer against the human World Cup champions
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and win.
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(Laughter)
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It's a true, actual goal.
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It's a very ambitious goal, but we truly believe we can do it.
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This is last year in China.
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We were the very first team in the United States that qualified
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in the humanoid RoboCup competition.
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This is this year in Austria.
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You're going to see the action is three against three,
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completely autonomous.
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(Video) (Crowd groans)
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DH: There you go. Yes!
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The robots track and they team-play amongst themselves.
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It's very impressive.
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It's really a research event,
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packaged in a more exciting competition event.
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What you see here is the beautiful Louis Vuitton Cup trophy.
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This is for the best humanoid.
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We'd like to bring this, for the first time, to the United States next year,
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so wish us luck.
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(Applause)
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Thank you.
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(Applause)
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DARwIn also has a lot of other talents.
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Last year, it actually conducted the Roanoke Symphony Orchestra
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for the holiday concert.
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This is the next generation robot, DARwIn IV,
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much smarter, faster, stronger.
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And it's trying to show off its ability:
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"I'm macho, I'm strong."
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(Laughter)
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"I can also do some Jackie Chan-motion, martial art movements."
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(Laughter)
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And it walks away. So this is DARwIn IV.
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Again, you'll be able to see it in the lobby.
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We truly believe this will be the very first running humanoid robot
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in the United States.
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So stay tuned.
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All right. So I showed you some of our exciting robots at work.
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So, what is the secret of our success?
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Where do we come up with these ideas?
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How do we develop these kinds of ideas?
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We have a fully autonomous vehicle
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that can drive into urban environments.
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We won a half a million dollars in the DARPA Urban Challenge.
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We also have the world's very first vehicle that can be driven by the blind.
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We call it the Blind Driver Challenge, very exciting.
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And many, many other robotics projects I want to talk about.
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These are just the awards that we won in 2007 fall
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from robotics competitions and those kinds of things.
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So really, we have five secrets.
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First is: Where do we get inspiration?
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Where do we get this spark of imagination?
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This is a true story, my personal story.
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At night, when I go to bed, at three, four in the morning,
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I lie down, close my eyes, and I see these lines and circles
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and different shapes floating around.
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And they assemble, and they form these kinds of mechanisms.
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And I think, "Ah, this is cool."
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So right next to my bed I keep a notebook, a journal,
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with a special pen that has an LED light on it,
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because I don't want to turn on the light and wake up my wife.
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So I see this, scribble everything down, draw things, and go to bed.
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Every day in the morning, the first thing I do,
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before my first cup of coffee, before I brush my teeth,
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I open my notebook.
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Many times it's empty; sometimes I have something there.
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If something's there, sometimes it's junk.
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But most of the time, I can't read my handwriting.
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Four in the morning -- what do you expect, right?
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So I need to decipher what I wrote.
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But sometimes I see this ingenious idea in there,
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and I have this eureka moment.
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I directly run to my home office, sit at my computer,
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I type in the ideas, I sketch things out
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and I keep a database of ideas.
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So when we have these calls for proposals,
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I try to find a match between my potential ideas
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and the problem.
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If there's a match, we write a research proposal,
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get the research funding in,
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and that's how we start our research programs.
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But just a spark of imagination is not good enough.
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How do we develop these kinds of ideas?
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At our lab RoMeLa, the Robotics and Mechanisms Laboratory,
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we have these fantastic brainstorming sessions.
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So we gather around, we discuss problems and solutions and talk about it.
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But before we start, we set this golden rule.
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The rule is:
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nobody criticizes anybody's ideas.
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Nobody criticizes any opinion.
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This is important, because many times, students fear or feel uncomfortable
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about how others might think about their opinions and thoughts.
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So once you do this, it is amazing how the students open up.
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They have these wacky, cool, crazy, brilliant ideas,
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and the whole room is just electrified with creative energy.
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And this is how we develop our ideas.
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Well, we're running out of time.
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One more thing I want to talk about is,
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you know, just a spark of idea and development is not good enough.
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There was a great TED moment -- I think it was Sir Ken Robinson, was it?
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He gave a talk about how education and school kill creativity.
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Well, actually, there's two sides to the story.
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So there is only so much one can do with just ingenious ideas
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and creativity and good engineering intuition.
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If you want to go beyond a tinkering,
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if you want to go beyond a hobby of robotics
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and really tackle the grand challenges of robotics
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through rigorous research,
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we need more than that.
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This is where school comes in.
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Batman, fighting against the bad guys,
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he has his utility belt, he has his grappling hook,
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he has all different kinds of gadgets.
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For us roboticists, engineers and scientists,
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these tools are the courses and classes you take in class.
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Math, differential equations.
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I have linear algebra, science, physics --
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even, nowadays, chemistry and biology, as you've seen.
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These are all the tools we need.
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So the more tools you have, for Batman,
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more effective at fighting the bad guys,
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for us, more tools to attack these kinds of big problems.
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So education is very important.
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Also -- it's not only about that.
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You also have to work really, really hard.
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So I always tell my students,
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"Work smart, then work hard."
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This picture in the back -- this is three in the morning.
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I guarantee if you come to our lab at 3, 4am,
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we have students working there,
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not because I tell them to, but because we are having too much fun.
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Which leads to the last topic:
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do not forget to have fun.
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That's really the secret of our success, we're having too much fun.
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I truly believe that highest productivity comes when you're having fun,
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and that's what we're doing.
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And there you go.
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Thank you so much.
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(Applause)
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About this website

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