Teachers' Domain; Physical Science/Engineering; Segway Technology: What's Newton Got to Do with It?

These high school students are experiencing first hand the amazing things that happen when you start to understand the laws of physics and the tools of engineering. They are participants in a national robotics competition sponsored by firsts. Each year First hundreds hundreds of high schools with hundreds of engineering companies. Their goal is to design and build robots to solve an engineering challenge. This year's Challenge was a game called Stack attack. A team whose robots carry push and stack the most boxes at the end of the game. Whims of the competitions founder is physicist mechanical engineer and inventor Dean Kamen. About that year ever since I was a kid my hobby has been thinking I look at the world and there are things about it that I've always thought I wonder why they don't do it this way. And I try to think about ways to change so that we can try it this way. Sometimes the change

requires that you. Take some existing technology. And sometimes it requires that you create some technology so that you can try to make the change. When engineers develop technologies they keep running into the laws of nature to say that you want to learn engineering or doing engineering and appreciate technology without. Understanding basic physics and the laws of nature would be like saying I want to learn to read before I learn the alphabet. The rules of nature are the underpinning of the tools of engineering Caymans mission is to foster innovation through invention. He holds more than 150 patents including life changing innovations like a portable kidney dialysis machine and I bought a mobility system designed for the physically challenged. You start with a problem without a solution. You start you say it's. Too bad that people that can't walk have to sit in a wheelchair because a wheelchair can't get them

up a curb or a flight of stairs. Even more importantly once they lose the ability to walk. Look at. Their colleagues eye to eye when they come down the hallway. I need to stand up to sign it. They can't get water from the sink. We need to fix that. We need to create something that will allow people that couldn't walk to enjoy the same basic freedoms that you and I take for granted. That would be a big innovation for the disabled community. The technology came and developed for I bought is also used. Way a vehicle designed to be a car alternative for short distances. These sophisticated machines employ the laws of physics to accomplish the goals of motion. And balance. Both. And Segway stay balanced using tilt sensors and a high tech version of the gyroscope. Once a gyroscope starts to spin it resists forces that try to

change the orientation of its spin axis. That gyroscopic effect the interaction between the spinning mass and the force is applied to it is very well understood and through the laws of nature we create tools in engineering so that we could create a miniature version of one of these gyros and say if the base of that Segway were that I but Tip's the motion of that gyro will give us indications about what's happened. And we can then take that information feed it to our computer which feeds those amplifiers that drive those wheels that keep us upright. Segues five gyroscopes monitor the driver center of gravity about 100 times per second. This keeps Segway upright and balanced. But for segue to actually move the technology must also account for Newton's

Laws of Motion. The greatest idea in the world if it requires that you violate Newton's laws that great elegant idea is going to see the brutal reality of the laws of nature it will work. When you combine Newton's laws you literally have a method by which you can understand how mass will react against other masses when forces are applied. Say break celebrates as Newton said a Acceleration is the ratio of f to M F over m. The force is applied by the wheels to the ground. The mass is you and the Segway and the acceleration that comes from your tipping your body forward which causes the torque of the wheels accelerates you in the same way. In some sense there's nothing about analyzing how a Segway works that's different than analyzing how central.

Gravity is pulling it down so it accelerates until it gets to the bottom. Now that it's at the bottom gravity isn't. Able to pull it any more in fact it starts going up the other side and Gravity is working in the opposite direction pulling it down. So for half the trip gravity accelerates it's changing its velocity and it gets to its highest velocity when it's at the bottom its highest speed is when it has no exhilaration. THEN it. Up and finally it comes to a stop. It has no velocity but it has the highest acceleration because it's hanging way out there and gravity accelerates and gives it more speed and that cycle repeats and it just keeps oscillating up and back it's called an oscillator. Well take that pendulum and turn it upside down. The mass that with the pendulum is now the driver on the Segway. When the driver leans forward or backward the gyroscopes detect the change in the center of gravity. They send signals to the motors to provide a force to move the wheels.

Or door backward in order to stay under the mass of the driver. All the laws that explain exactly how a pendulum works. Replied to sign a control system to make a Segway work here using the fact that there's a S.. It needs to be accelerated and you need a force in the pendulum the forces gravity and the Segway the forces come from the motors to the tires against the ground by leaning how mass forward for changing her center of gravity. She moves forward. And when her center of gravity is directly over segue she stops. The technology works on smooth or rough surfaces and even going up hills. After we finally process all the information we get a lot of power to make those wheels move. Where we going to get all that energy. We didn't want to use internal combustion engines because people use AI bots and segues inside buildings. We want it to be smooth and clean and quiet so the obvious way to run these devices was with electric motors and the electric

motors need batteries. The electric motors are powered by two rechargeable batteries that account for about a third of the weight of Segway. That sounds like a lot of battery but it takes only about a nickel's worth of electricity to operate Segway all day. If a few million people start getting around cities every day. With Segway technology instead of cars it would have a dramatic impact. On global fuel consumption and global pollution global warming congestion and is just fine. It's a neat way to get around short distances. If we do our job right and the world accept that we do. That's an innovation and that's exciting.