mtellin/Flickr.com

Sensing approaching disaster

October 26th, 2011 by Gene

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Unless you’re an engineer, you probably don’t think much about highway bridges. Until one falls down. We’ll think about bridges. Today, on Engineering Works!

We all remember the tragic collapse in 2007 of the I-35 bridge over the Mississippi River. More than a dozen people died and almost 150 were injured. That got people thinking about bridges in a big way. We have a lot of them to think about. Almost 600,000 across the United States. Almost 49,000 in Texas alone.

More than 150,000 – one in four – are in such bad shape that engineers worry about their safety. What to do? We could install sensors to warn us when a bridge gets near actual failure. But wiring up all our bridges would be prohibitively expensive. As much as $200,000 each. Multiply that by 600,000 bridges and things get out of hand in a hurry.

There may be a better way. An engineer in Maryland has developed a new sensor that could solve the problem. It’s wireless and costs about $20 each. They should last at least 10 years, and since they get their power from the sun, they don’t need batteries or wired electricity. You could put 500 of them on the average highway bridge for about $10,000. Still a lot of money, but doable.

He’s been testing them on real bridges in Maryland and they seem to work.

We don’t cross any bridges on our way home, so 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.

http://engineeringworks.tamu.edu

Start the discussion: Now and then somebody comes up with an idea that seems too good not to put it to work. This may be one of them. What other ways could we use to make our bridges safer?

For more:

http://newsdesk.umd.edu/vibrant/print.cfm?articleID=2474

http://www.gizmag.com/wireless-bridge-sensor/19380/?utm_source=Gizmag+Subscribers&utm_campaign=d496aef9ea-UA-2235360-4&utm_medium=email

http://sciencebusiness.technewslit.com/?p=5386

http://www.infrastructurereportcard.org/fact-sheet/bridges

http://www.statemaster.com/graph/trn_bri_tot_num-transportation-bridges-total-number

BNKR Aquitectura

Towering … down?

October 19th, 2011 by Gene

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Engineers in Mexico City are turning the time-tested skyscraper on its head. Literally. We’ll see what it means. Today, on Engineering Works!

If you’re in the business of building big new buildings in a place like Mexico City, you’ve got problems. The city is growing, and that means a big demand for new buildings, without much space to put them. About the only large open space left is the city’s main square, the Zocalo, in the center of town.

It seems ideal, but the Zocalo is important to Mexico City’s history. The National Palace, the Cathedral and important government buildings border it. The Zocalo is really important to a lot of people.

This is still where the architects and engineers want to build their big building. And they’ve come up with an idea they think will work. Build a tall office building – down – into the ground instead of – up – into the air.

Their plans call for the Earthscraper, they call it, to fill the plaza like a big upside-down pyramid and extend 55 stories into the ground. The top 10 floors would be an open museum of Aztec and Mayan artifacts. Then 10 floors of retail and residential space, followed at the bottom by 35 floors of office space.

At ground level, the Zocalo would remain, raised a little and bordered by big glass windows that would provide light to open spaces in the Earthscraper below.

We’ve explored this pyramid long enough for today. 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.

http://engineeringworks.tamu.edu

Start the discussion: We’re not sure about this one. It’s thinking outside the usual building box, but maybe it’s too far outside. What do you think?

For more:

http://www.bunkerarquitectura.com/

http://www.bunkerarquitectura.com/

http://www.archdaily.com/156357/the-earthscraper-bnkr-arquitectura/

Image in processed images/image by BNKR Aquitectura

Scaled Composites

A car that flies … really!

October 12th, 2011 by Gene

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Here’s an idea right out of the 1950s, updated to the 21st century. A flying car. Really. Today, on Engineering Works!

If you’re old enough to remember the 1950s, you’ll remember flying cars. If you’re not, flying cars were one of the technology dreams of those years that never made it into production. A car that flies. In your garage. Fly over that commuter traffic. Didn’t happen.

But now, aircraft designer Burt Rutan and the engineers at Rutan’s company, Scaled Composites, have brought the idea back to life. And it’s pretty cool. If you don’t follow aircraft design, Rutan and his crew designed the airplane that flew around the world in 1986 without stopping or refueling. Plus other imaginative advanced designs.

Rutan’s flying car features two cockpits, one for flying and one for driving and storage for the wings while it’s on the highway. It’s designed to take off and land in short distances, flies at 200 miles an hour and has a range of 700 miles. On the ground, it can maintain freeway speeds, handle in city traffic and stores in a garage.

Part of what makes it work is that its two engines drive generators that power electric motors that actually spin the propellers and drive the highway wheels. It has lithium-ion batteries to give extra power for takeoff and in emergencies.

Our truck doesn’t fly, but we’re still driving it home. 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.

http://engineeringworks.tamu.edu

Start the discussion: Rutan’s version of a flying car seems to be a lot closer to real life than the ideas we saw in the 1950s, but it’s still a big step from a prototype to production and sales. Anybody think they’re going to make it? Let us know.

For more:

http://www.aviationweek.com/aw/blogs/aviation_week/on_space_and_technology/index.jsp?plckController=Blog&plckBlogPage=BlogViewPost&newspaperUserId=a68cb417-3364-4fbf-a9dd-4feda680ec9c&plckPostId=Blog:a68cb417-3364-4fbf-a9dd-4feda680ec9cPost:ce084daa-4385-40ee-9664-b29f4a0cfecb&plckScript=blogScript&plckElementId=blogDest

http://www.scaled.com/images/uploads/news/BiPod_NewsRelease.pdf

http://en.wikipedia.org/wiki/Rutan_Voyager

http://www.gizmag.com/bipod-hybrid-flying-car/19258/?utm_source=Gizmag+Subscribers&utm_campaign=6297683929-UA-2235360-4&utm_medium=email

Michael Sharman/Flickr.com

A mystical side of engineering

October 5th, 2011 by Gene

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Engineers are hard-headed, practical folks. Not much given to mysticism. Sometimes, they might be. Come along, grasshopper. Today, on Engineering Works!

Today’s trip to engineering mysticism focuses on a Himalayan musical instrument called a Tibetan singing bowl. Singing bowls are bowl-shaped bells made of bronze alloy. When they’re hit or stroked with a mallet, they produce rich, ringing tones. They’re used in some meditation rituals.

What makes the bowls interesting to researchers is that unusual things start to happen if a bowl is struck or stroked while it has water in it. The bowl vibrates and the vibration causes tiny waves to form on the surface of the water.

Technically, these are called edge-induced Faraday waves. These Faraday waves are only the beginning. At a point, the waves become chaotic. They lose whatever pattern they have. Now, tiny droplets of water break loose from the surface and bounce across it.

The researchers used high speed cameras to record how the waves and droplets behave so they could measure and give it numbers. Then they worked out a mathematical model of what’s going on. Folks like us probably find it hard to see what’s important about what’s going on, but if you work with fluid dynamics, it’s just the thing.

It’s not just nifty science. Understanding what’s going on could be useful for engineers working with aerosols – everything from perfume sprays to fuel injection.

Our head feels like a Tibetan singing bowl, so we’re done. 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.

http://engineeringworks.tamu.edu

Start the discussion: This is a cautionary tale. We need to remember that sometimes things that seem outlandish can be pretty important.

For more:

http://content.usatoday.com/communities/sciencefair/post/2011/06/the-fluid-mechanics-of-tibetan-singing-bowls/1

http://blogs.physicstoday.org/newspicks/2011/07/the-fluid-dynamics-of-tibetan.html

http://iopscience.iop.org/0951-7715/24/8/R01

http://content.usatoday.com/communities/sciencefair/post/2011/06/the-fluid-mechanics-of-tibetan-singing-bowls/1?csp=34&utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+TP-ScienceFair+%28Tech+-+Science+Fair%29

To watch video od Faraday waves in a Tibetan singing bowl or listen to audio of what a singing bowl sounds like, check out these links:

http://www.youtube.com/watch?v=oob8zENYt0g&feature=player_embedded

http://www.freesound.org/tagsViewSingle.php?id=793

image in processed images Michael Sharman/Flickr.com