Archive for February, 2007

Digital Traffic

February 21st, 2007 by Gene

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It seems like cell phones connect us with everybody. Engineers have come up with something else your cell phone can do. We’ll listen in. Today, on Engineering Works!

It’s happened to everybody who’s ever driven in a city. You look ahead and you can see the traffic starting to thicken. What if there was a way to find out if that traffic ahead was just a slowdown or the beginning of gridlock? City planners and computer engineers have come up with an idea that someday may do just that.

An ambitious experiment on the crowded streets of Rome is tying together signals from cell phones with GPS devices on buses and taxis to see where vehicles and pedestrians are. Sophisticated signal processing methods help the researchers tell the difference between a cell phone signal from someone stuck in traffic and someone else just wandering down the sidewalk.

City planners are using the information to learn more about how Rome works. Traffic engineers use it to study how traffic flows in the city, especially during special events like the city’s annual White Nights festival or celebrations after the World Cup.

So far, the plots of these signals are just projected on big-screen maps in laboratories, but the engineers say that eventually you could get real-time updates on traffic around you so you could bypass congested areas.

Our traffic is beginning to slow down, so we’ll get off the street. See you next time.


Space Junk

February 14th, 2007 by dstmartin

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We’re going to talk trash like you’ve never seen — space junk. Today, on Engineering Works!

The next time you go outdoors, stop a minute and look straight up in the air. You can’t see it from here, but there’s a whole junkyard floating up above your head. It’s the stuff we’ve left behind from almost 50 years of space exploration.

Think about it. There’s so much junk in orbit up there that nobody knows for sure how much there really is. At least 100,000 pieces of stuff, maybe millions. More than 7,000 of them the size of a baseball or bigger. Some as small as chips of paint. In fact, a lot of it is chips of paint, from rockets and satellites. A few – broken down or worn-out satellites – are as big as washing machines.

Don’t snicker at those orbiting paint chips, either. They don’t sound like much, but they’re moving at more than 17,000 miles an hour. Anything moving that fast can do real damage if it hits something. One chip hit a window on the space shuttle. It gouged a crater as big as your thumbnail. Imagine what one of those dead satellites could do.

Engineers are designing shields to protect against collisions with orbiting junk. It’s a tough assignment – shields have to be strong enough to stop the junk before it hits anything important and light enough to lift into orbit.

Time to take out our trash. See you later.

Photo from


Bionic Arm

February 7th, 2007 by Gene
Bionic Arm

Courtesy of IEET


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It used to be that you could only find the bionic man or woman in science fiction. Biomedical engineers are changing that. Stay tuned.

If you wanted to see bionic arms or legs in action, you used to have to look back to 1970s television shows or Star Wars movies. Now, those fantasies are moving off the screen and into real life.

A young woman who lost an arm at the shoulder in a motorcycle accident is using a computer-controlled, electric-powered arm to do almost everything her own arm could do. Peel and eat a piece of fruit. Fold clothes. Even wash the dishes. And maybe best of all, all she has to do is think about what she wants to do, and it happens.

It works like this. Doctors moved the ends of the nerves that used to connect to her mangled arm to her chest. Electrodes on a harness detect tiny electric signals from those nerves and transmit them to a miniature computer. The computer translates them into signals that control small electric motors in her new arm and hand. When she wants to pick up an apple from the kitchen table, she thinks it and her arm, hand and fingers do it.

One problem — the arm and hand have no sense of touch. But everything else seems to be working fine.

Our arm isn’t computer controlled, but it’s still time to close the mike and leave. See you next time.