Archive for October, 2007

Precision agriculture

October 31st, 2007 by Gene

Old McDonald’s farm was never like this. We’ll spy on how satellites and other new technology are helping farmers keep track of their cows and corn — today on Engineering Works!

McDonald never heard of the global positioning system – GPS. But if he was farming these days, he’d probably be using global positioning system technology to keep track of his cows and all the other animals. GPS satellites, computers, new sensors and other high-tech tools are helping farmers “harvest” information from their fields – information they can use to harvest more crops.

Sensors in this cornfield, for instance, are measuring how fertile the soil is.

GPS satellites overhead read where the sensors are, and the farmer’s computer puts the data together and draws a map to show which areas need more fertilizer, and what kind.

Other sensors “see” where pests are chowing down on tasty crops, and map out where to apply insect killers. It’s all about making farming more efficient, doing the right things at the right time.

If you know exactly how much fertilizer and pesticide you need, and where you need it, you can be sure you’re applying enough without putting down too much. The same technology can also warn you about water pollution and other environmental problems before they get out of hand.

Bet Old McDonald wishes his farm was high-tech.

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 at

Shrinking camera

October 26th, 2007 by dstmartin

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

High Mileage

October 10th, 2007 by Gene

Hybrid cars get good gas mileage, but you ain’t seen nothing yet. We’ll look, today on Engineering Works!

If high gas prices are squeezing your budget, consider the engineers that design NASA space vehicles. These guys worry about the cost of fuel, but what’s really important is how much that fuel weighs. They’re always looking for ways to go farther on less.

They’ve outdone themselves this time with the Dawn mission that’s headed for the dwarf planet Ceres and the asteroid Vesta. If the engineers are right, the Dawn spacecraft will make the three billion mile trip on less than 72 gallons of fuel. That’s almost 42 million miles to the gallon. Move over, hybrids.

What’s important is that 72 gallons of Xenon weighs about a fifth of the conventional fuel the trip would need.

Of course, the fuel that’s driving Dawn wouldn’t work very well in your earth-bound car. It’s an exotic gas called Xenon. Dawn’s engine uses solar-generated electricity to pop electrons loose from Xenon atoms. An electrically charged screen pulls the electrons out the engine’s nozzle and that thrust pushes the spacecraft along. Gently.

Hold out your hand and lay a piece of paper on it. That’s the amount of force the Dawn’s Xenon-powered engine produces. It would take Dawn four days to accelerate from zero to 60. But by the time it gets to Vesta, it’ll be streaking along at 68 thousand miles an hour.

We’re about out of gas, so we’re shutting it down. 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

Measuring Disasters

October 10th, 2007 by Gene

When something bad happens, we like to know how bad it is. We’ll look at the numbers, today, on Engineering Works!

No disaster is good, but some are worse than others. For instance, most of us know that Hurricane Katrina started out as a category 5 hurricane, but was only a category 3 when it swamped New Orleans. And when we hear about tornadoes on the weather report, sometimes the meteorologist tells us that it was an F-1 or an F-3. It’s the same with earthquakes. The Richter scale lets us know how badly it shook things up.

Most of us know about the Richter scale, but you might not know that meteorologists measure hurricanes on the Saffir-Simpson scale, and tornadoes on the Fujita scale. Now nuclear engineers have come up with a scale to rate nuclear-related incidents. It’s called the International Nuclear Event Scale, or INES. It runs from zero – a deviation with no safety significance – to seven – a major accident. The 1979 accident at Russia’s Chernobyl reactor would have been a seven.

We started using the INES in 1992, and no sevens – major accidents – have occurred since then. Ten less serious incidents happened at U.S. nuclear plants last year. Two involved reactors. Most of the rest were spills of radioactive materials, some more serious than others. All of the incidents rated twos on the INES seven-point scale.

Our scale is the clock, and it’s ticking down to nothing. 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 at