'Jack' Project explores technology

The Annenberg Center was transformed into a virtual cyberworld as the American Music Theater Festival presented Crosswaves, a "festival of performance of technology" that began yesterday. The exhibit will continue through Sunday. Graduate students from the University's Center for Human Modeling and Simulation -- a lab within the School of Engineering and Applied Science -- demonstrated how to capture human motion using a virtual computer model known as "Jack." According to Engineering graduate student Sean Sheridan, the Jack Project began at the University about 20 years ago, when students developed the model of a human combining computer graphics with realistic motion. The students currently working on the project became involved with Crosswaves when AMTF contacted them looking for local graphics expertise and computer ability, Sheridan said. In yesterday's motion-capture demonstration, six magnetic sensors were placed on certain points on a human volunteer's body. As the subject moves, Jack also moves through a process called inverse kinematics, Engineering graduate student Rama Bindiganavale explained. Harold Sun, also an Engineering graduate student, explained that a large magnet creates a magnetic field, and the computer tracks the movement of the sensors in relation to the large magnet. The tracking process allows the movements of the virtual human to reflect those of the actual subject. "It's a good platform for experimenting with human models," Engineering graduate student Barry Reich explained. "It's the best software for accurately representing human movement." Sheridan explained that Jack's frame is made up of many polygons that each took a long time to create. "He doesn't look as human as he could because we are limited by technology," he said. "We can create a human that looks extremely realistic, but he couldn't move. "To make him move, we need to keep the polygon count as low as possible," Sheridan added. The graduate students are now in the process of creating an improved Jack who moves, yet looks more human-like, Sheridan said. But he added that they are still several years away from creating a "truly realistic human." The Jack Project has many practical applications, according to Sheridan. For example, Jack can be used to train surgeons. By performing virtual operations using Jack, doctors can perfect their surgical skills without actually working on a person. "By tracking motion and studying on a computer, you can become better at whatever you do," Sheridan said. Sheridan noted that a major automobile manufacturer has also used Jack. The computer model can be scaled to different heights, so the company can determine before building a car whether someone who is 6'5" could fit into the vehicle without hitting his head. "It saves money to study things in a virtual world," Sheridan explained. In addition to the motion-capture demonstration, Crosswaves includes other exhibits such as a "noise floor" and a Cyber Loft where experts help visitors explore the World Wide Web. There are also performances, including Graham Nash, of Crosby, Stills and Nash, singing with digital puppets portraying historical and imaginary characters.