The Science Behind Sid the Science Kid

For the past two months PBS has been treating us to the next wave of computer animation, without most viewers having the slightest idea. The show is Sid the Science Kid , and it’s produced by the Jim Henson Company. We’ve had digital puppetry on shows like The Wonder Pets and 3rd and Bird, we’ve had motion capture on a legion of feature films and shows like The Backyardigans, and we’ve had instantaneous digitally rendered backgrounds on Lazy Town. Where the Henson folks have now pressed ahead is in the instant rendering of motion captured animated characters/puppets. What that means in lay terms is that there are live performers filming on a set, but the recording is producing animated characters, right there in real time. This allows for improvisation, multiple takes, new angles, and other perks that usually are not the domain of the animated film. (This is not the Henson Company’s first foray into CGI animation, by the way, as they are responsible for the new television adaptation of Frances and the short film The Tortoise and the Hare.)

In the November issue Popular Science Gregory Mone interviewed Brian Henson. The interview is unfortunately not online, but here are some notes I took:

Brian Henson said, "I went through a spell in my teenage years where I absolutely was going to be an astrophysicist." That scientific bent says a great deal about why he participated in creating this new show.

They say "it brings an innovative mix of motion-capture technology and digital animation to the television world." 
"Typically, digital TV 'toons are computer-generated, because motion-capture-based animation takes too long to produce, but Henson's technology saves months of production time. It also allows for more lifelike scenes. The real-time rendering lets the puppeteers improvise and play off one another, creating a less scripted feel. As a result, Sid is visually crisp, but with interactions that can be just as nuanced as real life."

Henson says that typically Americans don't think about teaching science until 4th grade, but his curriculum developers stress we have to get to kids before age seven.

The show, like other science shows, is designed to teach kids to explore and become comfortable with the scientific method (as opposed to the rote memorization of scientific facts).

Answering a question on how they control characters, Henson said: "Two puppeteers control one character. A motion-capture arena outfitted with cameras and tracking devices records the movements of the puppeteer controlling the body and transfers those movements to the skeleton of the animated character. Then another puppeteer controls the head, face and voice of the character using a system initially developed for animatronics." ... "We came up with the idea in the mid-1990s, but we had to wait for processors to get cheap and fast enough. Creating an animation engine that can generate 24 frames per second with no delay so that a puppeteer can perform and see what the character is doing on the screen in real time was really difficult."

The result: "Sid is much more like the Muppets, where things can get a little wilder and sloppy. That's part of what's fun. ... With this technology, they [our puppeteers] can ad lib, they can improvise, which is a kind of energy that you don't see in animation because animation is normally carefully plotted."

"With our technique, the computer's not allowed to move anything. Anything that moves has either been moved by a performer or by a camera operator."

Similar information can be found in this Minneapolis Star-Tribune article and this post from the Muppet Newsflash blog. Here is the technical explanation from the Jim Henson Creature Workshop.


Dancer and actress Misty Rosas plays Sid's body. She’s seen here in her mocap suit, featuring four-foot feet that frankly remind me of the Teletubby costumes. Puppeteer Drew Massey is Sid's voice and face; he uses an animatronic glove to manipulate the face in real time (like having your hand in a puppet's face).

Here are a few more pictures of the puppeteers in action. And here is the show’s official PBS webpage.

Here’s another look at how they did it:




And here’s an example of the result: