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Photo of Prof. Cassell Virtually Real

Alex Pentland combines reality with virtual reality. One example demonstrated in this story is Silas, an intelligent virtual dog that responds to its environment. Following the premier of the Scientific American Frontiers Special Inventing the Future, Alex answered viewers' questions as part of an Ask the Scientists panel. Here are viewers' questions and his answers.

Q This new stuff is very exciting and wonderful, but what practical use will this be used for in the future?

A The first uses will be in games...imagine that the characters in a video game could really see you and hear you! Disney and similar companies are already working on making games that use this technology. Another use will be in museums; imagine an exhibit that could tell whether you were bored or if you wanted to hear more details.

Q What computer system do you use in the virtually real world?

A We use SGI Indy computers. They are about the same as a 200Mhz Pentium Pro PC, but they also have a place to plug in a video camera.

Q Dr. Pentland, I am a 7th grader in Los Angeles, Ca. I would like to know how long you've been working on your various inventions and research and also, what was your favorite subject in school when you were in the 7th grade?

A I've been working on Smart Rooms, Smart Cars and Smart Clothes for about four years, but I have been doing research for much longer. When I was in 7th grade I thought I would be a physicist, but in high school I thought I would be a psychologist. Then, when I was in college, I changed and thought I would be a mathematician, and later I thought I would be a computer programmer.

It seems that I change what I am interested in about every five years...that way you get to learn new things all the time. I think that everyone should plan to be lots of things in their life, not just one thing.

Q Due to all the discoveries and advancements we *are* able to see and hear in virtual reality, but will we ever be able to smell, touch, or taste in a virtual reality system?

A Smell and taste are hard, because it is difficult to get the chemicals that cause smell and taste onto the right part of the body and then off again in time for the next smell or taste. Touch is much easier, and already there are good virtual reality touch sensors/actuators, that can make you feel like you are touching brick, cloth, or other textures. However they still can't do water or make you think you are sitting in a chair...those are really hard problems.

Q Is it possible to get "stuck" in the virtual world?

A I can't imagine getting stuck in a virtual world anymore than you can get stuck in a book or magazine.

Q What did you use to project the composite image of the dog and Alan Alda?

A We have a big-screen TV that is actually made up of four smaller TV's sandwiched together. We take the camera input (Alan Alda) and use the computer (and SGI Indy) to add graphics to the video. The result then is projected on the big TV. The hard part, however, is to make sure that if Alan is standing where he would be in front of the virtual dog's head, then we don't draw the dog's head...that way it looks as if Alan and the dog are in the same room and that Alan is actually standing in front of the dog. Adding graphics to video is called 'augmented reality' rather than "virtual reality,'' because the real stuff (Alan) is still there...along with virtual stuff (the dog).

Q Why did you pick a dog over all other animals? And how did Silas get his name?

A We thought first about doing a virtual person, but that seemed too hard because people's behavior is too complicated. So first we did a virtual hamster, but the problem was that hamsters don't really do very much...they are too simple. Finally, we tried a virtual dog. Dogs have fairly complex behavior, and everyone likes them, so we kept the virtual dog. His name just came to us...someone started using it, and it stuck.

Q What do you think will be the most important thing to come out of research into virtual reality?

A Better ways of communicating between people. By allowing people to share virtual environments, they can interact in more interesting and complex ways than if we have to build a real environment (office, home, entertainment park) each time, and then physically travel there. Real environments and physical travel are just too expensive for everyone to do...whereas virtual environments will eventually be cheap enough for everyone.


Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.