Month: March 2008

Airplane on a Treadmill Definitive Analysis

I was late to the Airplane on a Treadmill party, so maybe you were too. Not since the famous Monty Hall and the Goat problem has so much hot air been generated by an online puzzler. Stated briefly, here is the problem:

Imagine a plane is sitting on a massive conveyor belt, as wide and as long as a runway. The conveyer belt is designed to exactly match the speed of the wheels, moving in the opposite direction. Can the plane take off?

What’s your answer? I must confess that I was seduced by the wrong conclusion for a while. This problem has now been around so long that the Myth Buster guys have had the time to demonstrate it on TV. Even if you have been aware of this problem for a few years, I recommend the writeup on the eponymous airplaneonatreadmill.com site entitled Airplane on a Treadmill Definitive Analysis. It’s a nice piece of writing about physics, and it does what so much of good science writing does: reframe the question using clearer terminology. In particular, look at his rewording of the problem into three separate but related problems.

Simply put, cars grab onto the ground to pull themselves forward. If you move the ground, they can’t go anywhere. Planes, in contrast, grab onto the air to pull themselves forward. If you move the ground, they really don’t care so much.

The Electric Company’s “Sign Song”

From my earliest TV-watching years, I remember we had a movable antenna on the roof that you could orient based on which channel you wanted to watch. You had your pick of three or four channels, depending on your appetite for static and snow.

By the time we got cable TV, thereby enabling our local PBS affiliate, I was already past the Mister Rogers and Sesame Street years. But I was in the demographic sweet spot for The Electric Company. And because nothing ever goes away anymore, I now have the pleasure of sitting in front of YouTube with my daughter and dredging up my favorite bits of 1970s educational TV.

For example, I was trying to remember all the words to the Sign Song that starts off like this: I like fish food, you do too. Don’t look now your hair is blue. Doesn’t sound so clever, eh? Well, here it is. Judge for yourself.

Just you try not humming that later on today.

In fact, looking back years later, I’m amazed at the talent they drummed up for that show. Morgan Freeman was a regular on the show. And although I knew that Tom Lehrer wrote the LY song for The Electric Company, I was surprised to learn via YouTube that he actually wrote a handful of other tunes, including the Silent E and the charming N Apostrophe T number that I only just discovered.

It’s amusing to think that my daughter is watching this on a small screen with low quality video, just like I did in the 70s, only for her it’s a TCP/IP feed to a small corner of my computer monitor.

BotJunkie and BigDog

I’ve started following the BotJunkie blog for fun stories and videos about robots. It reminds me how close I came to a career in robotics. I like the blog’s tag line: “From the folks who brought you OhGizmo.com, BotJunkie obsessively chronicles Man’s inevitable descent into cybernetic slavery.”

BotJunkie has plenty of weird stuff like snake-like locomotion (“Robot Snakes Crawl Up Your Pants”) and a robotic tennis ball slingshot for your pet dachshund, but every now and then I see a video that really knocks me flat. Look at the latest video from Boston Dynamics of the packbot BigDog.

Gott im Himmel! Did you see that great beast slip on the ice? What a piece of work! You can’t help but feel sympathy for the thing.

Robots really have turned the corner in the last few years. You can, for example, watch that dandified piece of clockwork, QRIO, mincing around on rollerskates. That was impressive, but it was really just a tarted-up excerpt from the film version of the Future. QRIO wouldn’t last five minutes in the real future, the one where you and I are headed. But BigDog… BigDog is from the future. The real future where he might have to kick ass in a Klondike barroom after humping over the Chilkoot Pass.

I don’t need a little Roomba with a vacuum attachment. I want a BigDog with a stick.

Evolution and geology

I just finished reading Sean Carroll’s book The Making of the Fittest. Subtitled “DNA and the Ultimate Forensic Record of Evolution”, it’s the follow-on book to Endless Forms Most Beautiful. In this book Carroll devotes several chapters to demonstrating how, against our natural intuition, there really is enough time (given a few hundred million years) for DNA to mutate bit by bit and still make amazing new structures like eyeballs, wings, and that pink dangly thing that hangs at the back of your mouth.

Carroll also points out that while almost everything is in flux, genetically speaking, there are some stretches of DNA so crucial to life that they never change. Which is to say, they can’t change because any variation would be fatal. Here, for example, is a six amino acid stretch that has been found in every single living thing: KNMITG. It’s an immortal sequence, unvarying across more than a billion years.

The last chapter deals with the controversies associated with teaching evolutionary theory in public schools. This is well-traveled ground, but it got me thinking about how much the opponents of evolution focus on man, monkeys, and biology class. But shouldn’t they be attacking geology too? Some of them do, insisting, for example, that the Grand Canyon formed during Noah’s flood. But it seems that a serious and consistent creationist ought to stick those little “this is only a theory” labels in every science book on the shelf. The astronomy book, the geology book, the physics book, they should all be thrown out the window along with The Origin of Species. Why is poor old Darwin always taking the heat?

Need your comics restored?

Got a 1938 Action Comics #1 sitting in a box in the attic? It might be worth half a million dollars. I learned that last Saturday.

My son recently turned nine, and at his birthday party I happened to be talking to another parent, talking the party talk, as one does. Talkety-talk-talk. What sort of work do you do? I inquired blithely. I am the pre-eminent restorer of high-value comics on the planet she replied serenely. NOTE: She didn’t actually say this. She was very casual and modest about it. But in fact she is the pre-eminent restorer of high-value comics on the planet. Her name is Susan Cicconi, and her site is called The Restoration Lab.com. If you have a weatherbeaten comic book that needs sprucing up, she is the person you need to talk to. Trained in Paris as a restorer specializing in high art, she eventually made the shift into pop culture, and business has been good.

I love having interesting neighbors.

More and more money has been pouring into comics collecting. Susan was the one who told me about the current price being fetched by Action Comics #1 (she has restored several of them over the years). Interestingly, she said that a recent trend may start to impact her business: you get more money for a valuable old comic that has never been restored. It reminds me of those appraisers on Antiques Roadshow: “If you hadn’t just scrubbed the filth off of this ugly-ass chair, it would be worth $1.4 million. But now all I can offer you is $3.50 and a couple of scratch tickets.”

Now that I think about it, there would be a big market for a new show called Antique Comics Roadshow.

The pestilence

No blogging last week because the pestilence, by which I mean the dread stomach bug, went through my house last week like a big stinky freight train.

As it happens, my four year old daughter and I have been watching (and re-watching) a DVD of Miyazaki’s My Neighbor Totoro, which is just about the ideal movie for a father and daughter to watch together, let me tell you. It’s also given us an opportunity to talk about other cultures, how they write in Japan, and what life is like there. Pursuant to this last, we took in a few YouTube videos, and as you can imagine, there is no shortage of weird Japanese YouTube videos, even among those that specialize in teaching basic Japanese.

I mention all this because we happened across this video that combined the two recent trends sweeping through our household: intestinal distress and Japanese cultural studies. For the record, this is a real video for teaching Japanese travelers useful phrases in English.

Don’t skip out before you see the aerobics section in the second half. If you’re anything like me, you’ll soon have new song to sing to yourself throughout the day.

Hum it a few times. It’s catchy.

Next: Print your furniture

In the latest issue of Dwell magazine I saw a short article on how a Dutch design firm called Freedom Of Creation is making furniture by printing it out. Three-dimensional printing is increasingly common as a tool for prototyping and design assessment, but that doesn’t go far enough to suit the folks at Freedom of Creation. They are actually printing out the final piece that gets delivered to the customer using a great big EOSINT polyamide laser sintering machine (a.k.a. the magic 3-d printer). Since the design goes directly from computer to product, no paper sketches or printouts are involved at any point. That’s just as well, because what they’re printing out, the Trabecula Table, is so complex (being modeled on the fine bone structure of bird bones) that drawing it wouldn’t be worth the trouble.

This is a good example of the future that is here but not yet widespread. At 12,500 euros, you might not jump at the chance to buy yourself a Trabecula Table. But other products, cheaper products, like this will follow soon enough.