(void*): A Cast of Characters

The Synthetic Characters Group at the MIT Media Lab presents (void*) : a cast of characters. The installation, located in the Millennium Motel area of SIGGRAPH99, explores interactions between autonomous and directable characters in a virtual space, and users in the physical space. Through our "buns and forks" interface, users can communicate with the virtual characters in an ever-changing social environment.  The group's aim is to build characters which come alive in the eyes, ears, and hands of the user -- in short, characters with minds of their own. By investing virtual characters with commonsense knowledge and letting their emotional states and personal motivations govern their actions, we can produce lifelike behavior which conveys feeling and intelligence. 

Dynamic, Emotional Characters The characters in the world possess rich behavior systems which govern their actions. Each actor is directable through a physical interface; at the same time, the inhabitants of the virtual world possess their own agendas, which invest their actions with emotional qualities. Unlike traditional video game characters, which have no free will, our characters react emotionally to the user, to their environment, and to each other. As a result, an emotional tension and resolution is present in their interactions which communicates a sense of presence. 

Between Physical and Virtual Evocative interfaces should foster rich, emotional interactions between the user and the characters. Drawing inspiration from the film "The Gold Rush", we have chosen as our interface Charlie Chaplin's famous "buns and forks". Using sensing technology designed by members of the Media Lab's Responsive Environments Group, the system can sense and interpret gestures from the buns, which translate into the characters' movements. But because the characters' actions are affected by their internal motivations and emotions, the interaction takes on a collaborative atmosphere (rather than traditionally one-sided direction). 

Interactive Music and Cinematography The world contains two other autonomous characters which are invisible to the eye: a music creature, dynamically composing a score for the installation, and a camera creature, whose set of desires and tendencies guide the view through the camera. The collection of music for the piece was composed by members of the group. However, the score is arranged in real-time by a character in the world, governed by the same sort of behavior system that guides the three actors. The emotional qualities of the characters in the scene can affect any aspect of the music; because the music creature uses the same information that affects the characters' emotions, the scene can be subjectively scored (ironically, a cinematic technique for which we owe a debt to Chaplin himself).  The camera system, developed by a graduate student in the group, acts as an autonomous cinematographer in the world. Like the characters and the music creature, the camera is governed by a rich behavior system which allows it to reflect the atmosphere of the scene through traditional filmmaking techniques. By putting its internal state on equal footing with those of the world's other characters, we are able to underscore the importance of actions and emotions, heightening the scene's emotional impact. 


  • Prof. Bruce Blumberg
  • Bill Tomlinson
  • Michael Patrick Johnson
  • Song-Yee Yoon
  • Marc Downie
  • Ari Benbasat
  • Jed Wahl
  • Dan Stiehl
  • Dephine Nain
  • Wally Holland
  • Matt Berlin
  • Dr. Joseph Paradiso 



    Appeared in SIGGRAPH '99: The Millennium Motel

Contact: Prof. Bruce Blumberg