Crave

A man wearing a costume covered in green LEDs at the Exploratorium for the opening night of the 2nd Skin digital-clothing exhibition.

(Credit: Daniel Terdiman/CNET News.com)

SAN FRANCISCO--A man wearing costumes covered head to toe in LEDs. Another man wearing a suit made of bubble wrap. A woman in a skirt made of Snickers wrappers. And a woman in a dress that generates power when she moves.

This was opening night of the 2nd Skin exhibit, a celebration of "imaginative designs in digital and analog clothing," at the Exploratorium here. And if the best and brightest in clothing embedded with technology and pure cacophony weren't on hand tonight, I can't even imagine where else they might be.

I didn't know quite what to expect at this event. But within minutes of walking through the door of this wonderful science museum, I was participating in one of the oddest group circles I've ever encountered. Known as ok2touch, a project by MIT Media Lab members Jay Silver and Jodi Finch, it was an outfit that was the central element in a circuit that can be made up of almost anything, as long as human skin is a part of it.

The idea, explained Silver, is that the outfit--which is designed with special metallic-based conductive thread--turns people's bodies into musical instruments, along with the bodies of anyone else around who is touched.

That's why Silver organized myself and a bunch of others into a big circle and then proceeded to explain how, as long as we all held hands, our collective movements would produce music on the outfit being worn by a model who was also in the circle.

And it didn't have to be hands: we could bump foreheads, and music would erupt from the outfit.

Adrian Vanallen poses with her dog in a dress that honors 18th-century anatomist Robert Hook

(Credit: Daniel Terdiman/CNET News.com)

"The project is about designing more human-to-nature contact," said Silver, pointing out that it works with water, flowers, and skin-on-skin, and that, for example, the circuit can go through water without any kind of danger. That's why, when I first walked up, Silver was having people run their fingers through some water on the ground, and the model's outfit was breaking out in music.

The larger message behind the project? That it's OK to touch each other.

"We learn so much about when it's not OK to touch," Silver said. But "touch is just such an important part of our humanness."

Next, I wandered over to a different area at the Exploratorium where a photographer was getting those people taking part in the evening's fashion show--the central event of the exhibition--to pose for pictures.

Amisha Gadani shows off her self-inflating dress during the opening of the 2nd Skin exhibition at the Exploratorium on Friday night. The dress is meant to be reminiscent of the actions of a blowfish.

(Credit: Daniel Terdiman/CNET News.com)

As Adrian Vanallen stepped down from the photographer's lights, I grabbed her. That's because she was wearing an outfit adorned with some sort of complex outline of the human anatomy--and she was carrying a small dog whose internal anatomy was also pictured on an outfit it was wearing.

Vanallen explained that her outfit represented an 18th-century anatomy circulation system created by English scientist Robert Hook, whom, she said, theorized that there were mini-humans inside our cells. Her outfit and that of her dog, then, were odes "to the history and the future of anatomy."

Nearby, Amisha Gadani was showing off her self-inflating dress. At least a couple of people seemed to see it as a dress that would autonomously re-enact the famous Marilyn Monroe scene from The Seven Year Itch, but Gadani said it was about something else entirely.

In fact, she said, the dress was based on blowfish behavior.

"Whenever I'm intimidated," she said, speaking in the guise of a human playing a blowfish, "I blow up. And I deflate when I feel like I'm safe again."

She said that someone had told her that the dress--which she actually inflates with a little control button she holds in her hand that operates a couple of fans built into the fabric--might be more like a mating ritual than something that scares people away.

"I'm OK with that," she said, "but it's definitely inspired by a blowfish."

For those interested in people watching, this was an evening to remember. Everywhere you looked there were men, women, and children dressed to the nines in all manner of outlandish outfits. Some were just for fun, and others were for the fashion show.

Some were dressed in various forms of circus attire, while others were adorned in what looked to be many, many, many layers of orange pom-poms.

And then there were the three people walking around together in matching full-body outfits of dozens and dozens of protruding circular foam pieces.

In the fashion show toward the end of the evening, my favorite piece might have been Amanda Parkes and Adam Kumpf's Piezing, a dress that is able to generate its own power based on the model's natural gestures while walking. The way it works, according to the evening's program, is that it "converts mechanical strain into electrical voltage as a person walks."

Another interesting piece in the digital part of the fashion show was Leah Buechley and Hunter Ewan's Reconfigure, a dancing outfit that creates music with the wearer's body motions. As the model wearing the dress strutted her stuff on the catwalk, the outfit broke out in all forms of music, a very odd experience.

Jill Haefele walks around the Exploratorium with her raining umbrella. It is covered with nasturtium, and has a reservoir filled with water on her back, which pumps a spray of rain onto the plants.

(Credit: Daniel Terdiman/CNET News.com)

Back off the catwalk, however, I ran into Jill Haefele, who works in the Exploratorium's living systems department, and she talked to me about her Portable Nasturtium plant, which was doubling as a rain-producing umbrella.

The way this works: Haefele had a container of water strapped to her back, out of which came a tube that was pumping water up into the air. It would then come down as "rain" on her umbrella, which was made with Nasturtium, a lovely green plant.

A man working with electroluminescent wire, otherwise known as EL wire, at the Exploratorium in San Francisco on Friday night. The EL wire was part of a larger creation he was making.

(Credit: Daniel Terdiman/CNET News.com)

As she walked around, the system was producing the rain and she was forced to keep on moving lest the water puddle up around her feet.

All in all, it was an enjoyable evening. Everywhere you looked, someone was wearing an outrageous outfit, often adorned with some form of lighted technology. In many cases, it was electroluminescent wire, or EL wire, a form of thin, battery-powered, wire somewhat reminiscent of neon.

As a longtime Burning Man veteran, I am very familiar with EL wire, and that annual countercultural arts festival is one of the first places the colored wire became well known.

But these days, it is cheaper and much stronger and brighter than it used to be. So all over the place at the Exploratorium, I was almost blinded by the intensity of the EL wire necklaces, hats, and other garments people were wearing.

While the opening night exhibition was a lot of fun, visitors can enjoy some of the pieces from the evening throughout the full 2nd Skin run, which lasts until Sept. 7.

SAN FRANCISCO--If you were at the Exploratorium here the other day, you might well have needed to be wary of flying objects.

That's because, way in the back of the world-class science exploration museum, senior scientist Paul Doherty was giving a primer on why the curveball--one of the most important pitches in baseball--curves.

Of course, being a hands-on kind of scientist, one who had kindly taken time out of his day to explain the physics of baseball, the only way Doherty could explain the science was to demonstrate it. So he was flinging balls everywhere, and boy were they curving.

Exploratorium senior scientist Paul Doherty demonstrates how to put spin on a ball and make it curve. The demonstration was part of a talk he gave on the physics of baseball.

(Credit: James Martin/CNET Networks)

Fear not, however. These were just foam balls, and even the one kid who got hit in the head barely noticed.

What was amazing, though, was that the kid who did take the ball in the head was far, far off the straight-line trajectory the ball began on. In fact, I would say that each time Doherty flung the ball--using a hand-made contraption designed to put a lot of spin on it--it must have curved off that trajectory by at least 45 degrees.

That's unlikely to happen with a real baseball, however, because of its weight. Whereas this foam ball weighed almost nothing.

Click here for video on baseball science: CNET News.com's Kara Tsuboi checks out the sweet spot on the bat and the stitches on the ball with the Oakland A's and with scientist Paul Doherty.

It turns out that for years, there was a whole school of thought that denied that a baseball could curve at all. Some, Doherty said, believed that because a ball falls with gravity, the "curve" was an illusion and wasn't in fact a side-to-side motion but rather a much easier to understand drop.

In 1949, according to an article in Science News, aeronautical engineer Ralph Lightfoot used a wind tunnel and high-speed photography to demonstrate conclusively that a pitched baseball could, in fact, curve.

And not just a little bit, Doherty said: Up to 17 full inches.

But why does the ball even curve in the first place? That's what my colleagues and I were there to find out, and Doherty did indeed learn us.

The answer boils down to the fact that the seams on a baseball "interact" with the air around the ball as it spins.

"It acts like a little rocket motor," said Doherty. "The spinning ball throws air down and behind" it.

One thing that's clear is that the ball must be spinning really fast, Doherty said. That explains why not everyone can throw a good curveball: It takes a lot of strength in a pitcher's arm and wrist to make the ball spin so quickly.

In actuality, the theory behind the curveball is quite simple. And if you extrapolate, it explains other pitches, and even rules in other sports, Doherty explained.

For example, he said that it is illegal, in golf, to use a ball that only has dimples on the sides because the ball will self-correct in flight and won't, in the end, curve way off track. Being able to control a tee shot, then, is what separates the pros from the weekend duffers. Really being able to control tee shots is what separates Tiger Woods from the rest of the pros.

But what about a knuckle ball or a spit ball?

Doherty said that a proper knuckle ball is thrown in such a way that the ball barely rotates at all--maybe one-and-a-half times between the pitcher and home plate.

With little spin, he added, the air goes turbulent as it encounters and flows around the ball and gets deflected to the side. And that means it's rather impossible to predict what the air will do and how the ball will move. A good knuckleball, in other words, wobbles all over the place and can be nearly impossible to hit.

Ah, but throw the knuckleball wrong and trouble happens to a pitcher.

"If you get it wrong," Doherty warned, "then you get a nice, fat, slow pitch that goes right across the plate."

In the big leagues, that's the recipe for a home run.

Speaking of home runs, the best way to hit one is to hit a pitch with the "sweet spot" on the bat.

So Doherty also spent some time explaining what that is, and why it matters.

Doherty also explained the physics of the 'sweet spot' on a baseball bat. To do so, he showed what happens when you hit a bat in various places with a mallet. Depending on where you hit the bat, energy goes to different places. When you hit the sweet spot, the energy goes straight into the ball.

(Credit: James Martin/CNET Networks)

Essentially, the sweet spot is the one area on a wooden baseball bat where, if the ball hits it there, the bat won't jump at all in the hitter's hands and where all the energy of the collision between the bat and the ball goes into the ball.

If the ball hits anywhere else on the bat, he explained, at least some of that energy is directed into the batter's hands, meaning the ball won't be hit as hard and also that there might be some pain involved.

"When you hit a ball with a baseball bat," he said, "sometimes it stings your hand and other times the ball just flies off the bat."

In other words, sometimes you don't hit the sweet spot, and sometimes you do.

To explain why hitting a ball sometimes hurts, he held a bat by the knob and smacked it over and over with a mallet. Where he hit it affected how the bat flew out of his hand.

When he hit the bat right in the center of its mass, he showed how the bat doesn't spin. And that results in the energy transferring to the batter's hands.

That's in part, he said, because the collision between the ball and the bat produced 8,000 pounds of force for a thousandth of a second, much of which goes into the hands.

The final score of a game, like this one between the Oakland A's and the Cleveland Indians often depends on who has more success, a pitcher trying to throw good curveballs or a hitter trying to hit pitches with the sweet spot of the bat.

(Credit: James Martin/CNET Networks)

If, on the other hand, the ball--or in this case, the mallet--hits the bat at the bottom of its barrel, it does spin.

So over and over, he smacked the mallet on the bat, and the bat flew, spinning, out of his hand. It must have been a rather odd sight for any passers-by.

This doesn't produce Hall of Fame hitters, he suggested. Instead, lots of ground outs.

But somewhere in between the barrel and the center of mass, there's a small point where, when hit by a ball--or a mallet--the bat produces a loud, satisfying "crack" and either the ball flies off it, or the bat shoots off the mallet without spinning, dropping directly away.

"It's the center of percussion," he said, "the place where you hit it, and it doesn't jump in your hands. There's a couple of inches to hit that home run."

The trick is, Doherty explained, the sweet spot is different on every bat. So in order to find it, it takes trial and error. We know it's between the center of mass and the end of the barrel, but where exactly depends on the individual bat.

But, regardless, the message is clear: "If you want to hit that home run on opening day," Doherty said, "hit that sweet spot."

The Pi string has more than 4,000 colored beads on it, each color representing a digit from 0 to 9, and added at the exact place in the progression of digits in Pi. The string is the creation of Exploratorium employee and Pi Day creator Larry Shaw.

(Credit: Daniel Terdiman/CNET Networks)

SAN FRANCISCO--If ever a mathematician could be excited about a date, today would be it.

That's because it's Pi Day, March 14, or, for you Americans, 3/14. And since pi--the ratio of a circle's circumference to its diameter--is casually said to be 3.14159, today's the big day.

That's why I spent a big part of my day at the Exploratorium here for the science museum's 20th annual Pi Day celebration.

The brainchild of longtime Exploratorium employee Larry Shaw, the day's festivities celebrated the popular irrational number with a series of pi-related activities and events, mainly aimed at kids, and even one very small special guest.

Click here for more photos.

(Credit: Daniel Terdiman/CNET Networks)

Among the items on the agenda Friday was an "ask a scientist's Pi Day puzzle" session, a Pi procession, a "why Pi" lecture, and a demonstration by a world-champion pizza tosser.

So I thought I'd start my day at the Exploratorium by asking Shaw, a longtime Exploratorium employee and the originator of Pi Day in 1988, why pi means so much to so many people.

"It's how to get from one dimension to another," said Shaw, referring to the fact that the formula for determining pi involves both a two-dimensional object, a circle's circumference, and one with only one dimension, the circle's diameter.

He added that pi means a lot to so many because of its metaphysical properties. It's irrational, he said, and transcendental, and while there's a procedure for how to calculate it, it's also infinite.

"You can find the next number," Shaw added, "but you can't predict it."

Later, I asked Paul Doherty, the Exploratorium's senior scientist, why he thought pi is so exciting to so many people.

"There are people in the world who are interested in rock and roll and who are interested in sports," Doherty said. "We're just interested in mathematics, and we want to provide really good, interesting information for those people who have a deep interest in mathematics...and for those who don't know they might."

Doherty said pi is "this amazingly simple-to-define thing that produces a number that's just never ending, and this idea that something so simple can generate a number that's never ending is just amazing."

In part, pi's popularity has to do with its randomness, Doherty said. He pointed to other infinite numbers, like one-third or the square root of 2. But he argued those numbers are boring.

Robyn Barker holds her son, Pi Barker. She and her husband named Pi because of the "infinite possibilities" in his life.

(Credit: Daniel Terdiman/CNET Networks)

"With pi," he said, "it not only never ends, but it never repeats."

Of course, in some places, pi actually does repeat. Doherty pointed out that somewhere, hidden in the first 2 billion digits of pi, there's eight eights in a row, as well as a sequence of 1, 2, 3, 4, 5, 6, 7, 8, and 9.

But, he pointed out, those are just pure coincidences, a function of the probability of getting any kind of sequence of numbers in a string currently over a trillion digits long.

And speaking of strings, the term means different things to Shaw. Among the attractions he offered Friday was the "Pi string," a long string of colored beads that represents the first 4,000-plus digits of pi.

Over the years of doing Pi Days, Shaw has had participants add more beads to the string, and on Friday, he had set up 10 cups with beads for people to add to the string based on a print-out of thousands and thousands of digits. Each cup contained a single color bead and each color represented a single digit.

One year, he said, someone put one of the wrong colored beads on, but he was able to fix the string before anyone else noticed.

As to how anyone would have the attention to detail to notice something like that, well, that's another matter. But for people like Shaw--and mathematicians in general--it's precisely this detail that matters when dealing with something as both exact and inexact as pi.

One Pi Day attendee who may not yet appreciate the significance of the number is Pi Barker, the son of Chad and Robyn Barker.

The two named their new son--he was born December 6, 2007--Pi because of what they saw as the metaphysical meanings associated with the number.

"Since pi is an infinite decimal," said Robyn Barker, "it's a gift for us to give him. So wherever he is, it's a reminder of his infinite possibilities."

Pi's father, Chad, who is a manager in Google's strategic partnerships group, added that he and his wife appreciated giving their son a name that calls to mind the circular nature of life as well as the never-ending nature of life.

As to whether their families and friends appreciate the name Pi, that may still be to be determined. Especially when little Pi makes it to school and has to contend with the inevitable cruel nature of little children.