Archive for August, 2009

You and the terrorist

August 25th, 2009 by Gene
 
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Photo:EPA/islamizationwatch

Here’s a strange thought to start your day: You probably have something in common with a terrorist. We’ll think about that, today on Engineering Works!

We usually don’t think of terrorists as firing up the grill for a backyard barbecue. That’s something folks like us do. But the chances are pretty good that when you hit the switch to light your gas-fired grill, you’re using technology terrorists use for what they do.

Sounds scary, huh? It’s not, really. Here’s what’s going on. When you push that button to ignite the gas to grill your steak, the pressure from your finger bends a small crystal down in the switch. Just a little. Engineers call it a piezoelectric crystal. That bending causes stresses in the crystal and out comes an electric current. Enough to make a spark to touch off the gas.

One of terrorists’ favorite weapons is a rocket launcher called an R-P-G. If you were an explosives expert, you could take apart the warhead of an R-P-G rocket. Don’t try this at home, kids. Inside, there’s a thing called a detonator that makes the explosive explode when the rocket hits something.

Inside the detonator is a piezoelectric crystal, a lot like the one in your gas grill. When the rocket hits something, the force bends that crystal, and the electricity it makes touches off the warhead.

Our crystal has taken about all the pressure we can stand, so we’re out of here. We’ll see you next time.

Engineering Works! is made possible by Texas A&M Engineering and produced by KAMU-FM in College Station. Learn more about engineering. Visit us on the World Wide Web. Engineeringworks.tamu.edu.

Flywheel power

August 19th, 2009 by Gene
 
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Photo: Beacon Power Corp.

One of the newest ideas for storing a lot of electricity is also an old idea. We’re going around in circles. Today, on Engineering Works!

Everybody knows about electricity, even if all you know is that we use a lot of it.

Here’s the problem. We use a lot more electricity at two in the afternoon than we do at two in the morning. This means we need enough generators to give us the electricity we use during the day. At night, when businesses are closed and most of us are asleep, we use a lot less electricity and we need a lot fewer generators. But they’re still there and they’re not doing anything. That’s expensive and wasteful.

Power engineers think we can use some old technology to solve the problem. It’s called a flywheel, and the idea has been around a long time. Think potter’s wheel. The engine in your car has a flywheel, too. It stores some of the energy the engine produces to help it run smoothly, especially at slow speeds.

The new flywheels are really high-tech. And really heavy, more than a ton each. They spin on magnetic bearings. At twice the speed of sound. The idea is to spin them up when power demand is low and use the energy they store to turn generators when demand is high. That should help even out the load on generating systems.

Our flywheel is running down, and it’s time to leave. See you next time.

EngineeringWorks! is made possible by Texas A&M Engineering and produced by KAMU-FM in College Station. Learn more about engineering. Visit us on the World Wide Web. Engineeringworks.tamu.edu.

The incredible shrinking camera

August 11th, 2009 by Gene
 
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Photo: Euchiasmus/Wikipedia

Sometimes, they say, life imitates art. So does engineering — sort of. We’ll see how, today On Engineering Works!

If you’re a fan of campy science fiction movies, you might remember the 1966 flick, Fantastic Voyage. In the movie, a submarine with a crew of medical experts is shrunk and injected into the bloodstream of a guy in a coma. Except for Raquel Welch, the movie is pretty forgettable. Of course, shrinking the submarine is pretty neat, too.

Now, biomedical engineers have pulled off something like the shrinking submarine, except it’s real. This time, it’s a miniature camera in a capsule. No Raquel Welch. Sorry, guys. Doctors use this camera capsule to examine the inside of the small intestine, one part of the body that’s hard to reach with more conventional diagnostic tools. The capsule is bigger than the fictional submarine — about the size of a big vitamin capsule. It carries a camera on a computer chip, light source, radio transmitter and a battery.

Here’s how it works. You swallow the capsule and it passes through your stomach to your small intestine, taking pictures as it goes. The images are transmitted to a receiver on a belt, powered by its own battery pack. In a day or so, the capsule passes on through the rest of your digestive system and your doctor collects the images from the receiver and analyzes them. Pretty cool.

Our capsule has gone where all capsules go, and we’re done. See you next time.

EngineeringWorks! is made possible by Texas A&M Engineering and produced by KAMU-FM in College Station. We’re on the World Wide Web, too. Visit us at engineeringworks.tamu.edu.

Running water

August 4th, 2009 by Gene
 
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Photo: Chaim Zvi/Flickr.com

Turn on the tap and the water comes out. No big deal. We’ll drink to that. Today, on Engineering Works!

Most of the time, most places, in the United States, getting enough water is no big deal. Kitchen sink, bathroom shower – turn them on and the water comes out. Making that happen is more complicated – and less certain – than you think.

Consider this. It takes a million miles of pipe to get the water to everyone who takes that drink. Plus 24,000 storage tanks and more than 14 million valves. Almost seven million fire hydrants. And water experts estimate that there are about 25 breaks in every hundred miles of water main. At an average cost of $3,000 each, fixing those breaks is an expensive job.

Getting the water to you is only the beginning. It has to be clean and good to drink. Water spends a lot of time in storage before it gets to you. And the longer between when it’s purified and you drink it, the more opportunity it has to pick up germs and other nasty stuff.

Water quality engineers are working hard to come up with the best ways to get that water to you and be sure it’s clean when it gets there. But it’s a truly complicated problem. Solving it involves everything from construction and understanding how water behaves as it moves to chemistry and microbiology.

Somebody just closed our tap and we’re through. See you next time.

Engineering Works! is made possible by Texas A&M Engineering and produced by KAMU-FM in College Station. Learn more about engineering. Visit us on the World Wide Web. Engineeringworks.tamu.edu.