Archive for July, 2003

Keep your eye on the chip

July 30th, 2003 by dstmartin

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Everywhere you look these days, there’s a computer chip. Today, we’re going to see how these bits of silicon are going to help blind people see, on Engineering Works!

First, a quick anatomy lesson. We see things in front of us because our eyes focus images of what they’re looking at onto specialized cells inside. Sort of like focusing a camera. These cells pass on the image to the optic nerve at the back of our eye, which connects to our brains. Simple, right?

Normally, this works pretty well. But sometimes, because of diseases like macular degeneration and retinitis pigmentosa, those cells stop working. You can’t see any more.

This is where the computer chip comes in. Scientists and engineers have come up with a nifty little device that replaces those malfunctioning cells with a tiny computer chip. Combine it with an equally tiny video camera and it’s like seeing. Almost.

The computer chip floats inside your eye, right in front of those malfunctioning cells. A bundle of electrodes connect it to the optic nerve. The video camera rides on a frame that you’d wear like spectacles. It transmits its images to the chip by radio.

Some real engineering went into this thing. The computer chip is designed to have the same bouyancy as the fluid inside your eye. That means that it stays put where it needs to be, even when your eye moves. And the chip gets its power from the radio signal that carries the video image. No batteries to change.

It won’t be exactly like seeing, at least at first. But it will be a lot better than seeing nothing at all. The first versions should be available in a year or two. And the designers expect new versions now on the drawing board will be better. So, keep your eye on the chip.


Focus on digital photography

July 23rd, 2003 by dstmartin

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In the world of photography, digital is the magic word these days. But there’s no magic in digital cameras, just good engineering. We’ll focus on digital cameras, today on Engineering Works.

That new digital camera you used to take those snapshots of your kids at the Grand Canyon looks kind of like your old point-and-shoot film camera, but it’s not. It’s the difference between chemistry and physics.

Your old film camera used chemistry to catch Uncle Steve with the lamp on his head at his birthday party. Light coming through the lens changed chemicals on the film to record the scene in your viewfinder. That same light in your digital camera causes tiny sensors on a computer chip to record a series of ones and zeros. Different colors and tones give you different sequences. A tiny computer in the camera converts those numbers into pictures you can see on a screen.

Unlike your old snapshots, you can e-mail your digital photos to the whole family. And you can print them yourself at home instead of sending them off to be developed.

The ideas behind that new camera go all the way back to 1951, when the first video tape recorder captured images from TV. NASA started using digital technology to record signals from space probes in the 1960s. It was even used in spy satellites.

The first electronic camera was patented by Texas Instruments in 1972, and Sony sold the first commercial electronic camera in 1981. But the first real digital camera to work with your home computer didn’t appear until 1994. Thank you, Apple.

Now, digital cameras are as common as, well, ones and zeros. Say cheese!


High-tech, portable emergency room

July 16th, 2003 by dstmartin

Hurting yourself is never fun. We’ll learn how emergency medical care a long way from the emergency room can get better, today on Engineering Works.

Close your eyes and picture this. A desert landscape as seen from a trail high in the Chisos Mountains in West Texas’ Big Bend National Park. Nothing but miles and miles of rocks and sun. Beautiful. Then a pebble rolls under your boot and you’re tumbling down a near-vertical slope. When the dust settles, you’re at the bottom and you’re hurt – bad.

If that happened to you today, it could be a grim picture. The nearest clinic is more than 90 miles away, and it’s more than three-hundred miles to the closest level three trauma hospital with a top emergency room.

Engineers and computer scientists are using high-tech electronics to paint a brighter picture for sick or injured people in remote areas like wide-open West Texas. They’re combining high-speed wireless data transmission with real-time video and audio links into a portable package that will ride in an ambulance.

Emergency medical technicians will be able to confer directly with trauma specialists in the far-away emergency room. They won’t have to wait ’til they get to the hospital to begin treating severe injuries or illness. Eventually, the system will tie medics on far-flung oil platforms or orbiting space stations to expert advice from the emergency room.

It will be a while before this system is up and running, but emergency medics are already field-testing the idea in several Texas counties.

Food irradiation

July 9th, 2003 by dstmartin

Everybody does it. Nuke it! Today on Engineering Works, we’ll find out how the biggest microwave oven you ever thought of makes food and other things safer.

Microwave ovens and food just seem to go together. They’re pretty handy. A minute or so and last night’s leftover fried rice turns into a tasty lunch today.

Food engineers are using a device sort of like a microwave on steroids to rid all kinds of food of unpleasant bacteria like salmonella and E-coli that can make us sick. It’s called irradiation.

Irradiation is causing quite a stir in the world of food. Some people think it’s a great idea. In one simple process, they say, food can be made safe from contamination by bacteria. And you can store irradiated food almost forever.

Other people think it’s scary. As soon as you say irradiation, they start thinking about things that glow in the dark.

Actually, we’ve been irradiating food for a long time; more than 90 years, in fact. And no one’s been contaminated yet by irradiated food. All the food the astronauts eat while flying the space shuttle or circling the globe on the international space station has been irradiated. And you’ve been using irradiated spices and cosmetics for years.

So the next time someone mentions irradiated food think of fried rice and astronauts and dig in. You’re in good company.

Global Positioning System

July 2nd, 2003 by dstmartin

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You’ve seen the commercials on TV. You’re driving your car and you’re lost. Push a button on the dashboard and you’re found. We’ll figure out how they do that today on Engineering Works.

It starts with a herd of orbiting satellites and something called the Global Positioning System. About 11-thousand miles above us, 24 satellites are circling the globe. They’re positioned so that if you could see that far, you could always see at least six of them, no matter where you were standing.

Because radio signals travel in a straight line, like light, that means that a GPS receiver in your hand or in your car will always be able to get signals from those six satellites. Your receiver can measure how far away each satellite is, and then put together all the measurements and calculate almost exactly where you are.

It works no matter where you are, deep in the Brazilian rain forest or across town from home. Engineers building the Chunnel from France to England used GPS to make sure both ends of the tunnel met in the middle.

The people who first thought up the Global Positioning System expected it would be used by the military. You can see how important it is for soldiers to know where they are. Anywhere. Any time. In any kind of weather. And very accurately.

It works. The military bought about a thousand GPS receivers at the beginning of the Gulf War in 1991. The system works so well that by the end of the conflict, more than nine-thousand were being used, by foot soldiers; in airplanes, ships, tanks.

Now we can use it to keep from getting lost or to get found if we do get lost. And without having to ask for directions.