The Aspen Project

    Late at night on July 3, 1976,  the Israelis launched an extraordinarily successful strike on the Entebbe, Uganda, airport,  rescuing 103 hostages taken prisoner by pro-Palestinian guerillas,  who were give safe haven by dictator Idi Amin.  By the time the one-hour operation ended,  twenty to fourty Ugandan troops were killed and all seven hijackers were dead.  Only one Israeli soldier and three hostages also lost their lives.  This impressed the American military so much that the Advanced Research Projects Agency,  ARPA,  was asked to investigate electronic ways in which American commandos could get the kind of training the Israelis had had to succeed at Entebbe.
    What the Israelis had done was build in the desert a physical model,  to scale,  of the Entebbe Airport (which was easy for them to do because Israeli engineers had designed the airport when the two nations were on friendly terms).  The commandos then practiced landings and takeoffs,  as well as simulated assaults on this accurate mock-up.  By the time they arrived in Uganda for the "real thing," they had an extraordinarily keen spatial and experiental sense of the place,  alloowing them to perform like natives.  What a simple and terrific idea.
    However,  the idea as a physical embodiment was not extensible,  in that we just could not build replicas of every potential hostage situation or terrorist targets like airports and embassies.  We needed to do this with computers.  Once again,  we had to use bits,  not atoms. But computer graphics alone, like that used in flight simulators, was inadequate.  Whatever system was developed would need the full photorealism of a Hollywood stage set to convery a real sense of place and a feel for the surrounding environment.
    My colleagues and I proposed a simple solution. It used vidoediscs to allow the user to drive down corridors or streets,  as if the vehicle were located in those corridors on those streets.  As our test case,  we chose Aspen, Colorado where the city's grid and size were manageable and where the townsfolk were sufficiently odd that they didn't worry about a homemade film truck driving down the middle of all the streets for several weeks,  during several seasons.
    The way the system worked was simple.  Every street was filmed, in each direction, by taking a frame every three feet. Similarly, every turn was filmed in both directions.  By putting the straight street segments on one videodisc and the curves on the other,  the computer could give you a seamless driving experience.  As you approached an intersection,  say,  disc player 1,  player 2 would line itself up at the intersection, and in the event that you decided to turn right or left,  it would play that segment.  When playing the turn, player 1 would then be free to seek out the straight segment of street onto which you had turned and,  once again,  would seemlessly play it as you ended your turn and started down the new street.
    In 1978 the Aspen Project was magic.  You could look out your side window, stop in front of a building (like the police station), go inside,  have a conversation with the police chief, dial in differnt seasons,  see buildings as they were forty years before, get guided tours, helicopter over maps, turn the city into animation, join a bar scene, and leave a trail like Ariadne's thread to help you get back to where you started.  Multimedia was born.
    The project was so successful that military contractors were hired to build working prototypes for the field, with the idea of protecting airports and embassies against terrorists. Ironically, one of the first sites to be commissioned was Tehran.  Alas,  it was not done soon enough.