Archive for December, 2006

Car Data

December 21st, 2006 by Gene

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Everybody knows about the flight data recorders in commercial airliners. They’re the black boxes accident investigators use to help figure out why airplane crashes happen. What you probably don’t know is that your car has a black box a lot like them.

Automakers in the United States began installing data recorders in the 1970s when the first air bags became available. These tiny computers sense when your car slows down suddenly, like in a collision. Then it sends a signal that pops your airbag. It all happens in an instant — so fast that your airbag stops you from slamming into the steering wheel.

Starting in 1999, more-complex recorders began collecting more information — your speed, how fast the engine is turning, how hard you’re pushing the accelerator; if you’re pushing on the brake pedal and how hard; whether your seatbelt is fastened. If you have a crash, engineers can put together this information with injury reports to help improve performance or in recalls of faulty equipment.

Right now, these recorders store data from five seconds before a crash. That’s enough to tell the engineers what they want to know. Some people think collecting and storing more than five seconds’ worth of information would be a good idea. Others aren’t sure it’s necessary.

Anyway, it’s time to take our data and drive on out of here.


Slow Space Vehicle

December 6th, 2006 by dstmartin

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That’s a new space vehicle on the way to the moon. We’ll find out why it’s got engineers so excited, today on Engineering Works!

That hiss is a new spacecraft engine. An ion drive engine, just like on Star Trek. Except this one is real. It’s what boosted the European Space Agency’s Smart-1 space vehicle from Earth orbit to the moon.

The Smart-One’s engine is completely unlike the rocket engines that took astronauts to the moon and back. A regular rocket got Smart-1 into orbit, but then the ion drive engine took over. The ion drive used electrons from xenon gas to push the spacecraft through space. Electricity from solar panels rips the electrons loose from xenon atoms and they fizz out a nozzle in the back and push the spacecraft along with a force of about five-grams. That’s not much. Strike a match and blow it out. Congratulations! You just produced more thrust than Smart-1’s engine. But over a long trip those five grams add up to a lot of speed. In fact, engineers say that ion drive may be faster than regular rocket engines for long trips.

The best part may be that ion engines don’t need heavy tanks of propellants. Most of the weight conventional rockets carry into space is fuel and oxygen. All the fuel Smart-One carried to the moon weighed 176 pounds.

It’s time to fire up our engines and get out of here. See you next time.