straight up
"This extraordinary project brought together sixty-three American and Japanese artists, engineers and scientists."
E.A.T. Pepsi Pavilion


Great Big Mirror Dome film

Pepsi Pavilion <1970>

The last project I will describe in detail is the Pepsi Pavilion. In late 1968, Pepsi-Cola approached E.A.T. to design and program a Pavilion for Expo '70 in Osaka, Japan. Robert Breer and I chose Robert Whitman, Frosty Myers and David Tudor to work on the first design.

The roof of the Buckminster Fuller style geodesic dome was covered by a water vapor cloud sculpture, designed by Fujiko Nakaya. When fully operational, the fog system was capable of generating a 6 foot thick 150 foot diameter area of fog. And on the terrace are seven of Robert Breer's Floats, six-foot high sculptures which moved around at less than 2 feet per minute, emitting sound.

The cloud was produced when water under pressure of 500 psi was pushed through jet-spray nozzles and broken up into the water drops small enough to remain suspended in air. Strands of nozzles were installed in the ridges and valleys on the top section of the roof. The system used 2520 jet-spray nozzles.

The three legged black poles are part of Frosty Myers' Light Frame sculpture. Four such poles of different heights, were set in a square 130 feet apart at each corner of the Pavilion plaza. At the top of each pole were two 500-watt, high intensity xenon lights. Each light was directed toward the light of the neighboring tower, creating a very narrow pencil beam of light between each tower. This created a well-defined tilted square of white light framing the pavilion at night.

Robert Breer's Floats moved slowly around the plaza. When they hit an obstacle or were pushed they would reverse direction. A battery-operated tape recorder inside each Float played low sounds like sawing, a group of people describing a view in English, a truck starting up and driving away, humpback whale songs. The kids loved them, as you can see from the slide on the left.

The visitor entered through a tunnel and descended into a dark clam-shaped room lit only by moving patterns of laser light. The Clam Room is where people first entered the pavilion. Lowell Cross designed the laser deflection system which used the four colors from a krypton laser. The highly sensitive mirrors in the system could vibrate up to rates of 500 cycles per second and were activated from the sound system in the mirror dome.

Upstairs the main space of the Pavilion was a 90-foot diameter 210-degree spherical mirror made of aluminized mylar. The artists conceived of this space as performance area that could be used by many visiting artists during Expo '70.

The mirror fulfilled all our expectations. Our architect John Pearce devised an ingenious way the mylar mirror could be fitted inside an air tight cage structure. A slight vacuum of less than 1/1000 of an atmosphere, which could be handled by a couple of good sized fans, would be sufficient to hold up the mirror. By having a negative pressure air structure, there was no need for cumbersome air locks.

This optical effect in a spherical mirror of producing a real image resembles that of a hologram. The difference is that because of the size of our mirror, a spectator looking at an image could walk around the image and see it from all sides.

The space in the mirror was gentle and poetic, rich and always changing. It was complex in spite of its simplicity. We discovered new and complicated optical effects every day. The slide to the right is projected upside down. Once the visitors could see themselves as a real image in the mirror, the reaction was incredible. It created much more excitement than we ever could have expected.

David Tudor designed the sound system as an "instrument" with 32 inputs and 37 speakers arranged in a in a rhombic grid on the surface of the dome behind the mirror. Sound could be moved at varying speeds linearly across the dome and in circles around the dome. Sound could be shifted abruptly from any one speaker to any other speaker, creating point sources of sound. All speakers were capable of giving out the same sound. The lights and sound could either be pre-programmed or controlled in real time by the artists from a console at one side of the dome.

The floor was divided into 10 areas made up of different materials, such as astroturf, rough wood, slate, tile, asphalt. Through handsets, like the one held by the boy in the left slide, visitors could hear specific sounds on each different floor material. On the tile floor: horses hooves and shattering glass; on the astroturf: ducks, frogs, cicadas and lions roaring. These sounds were transmitted from wire loops embedded in the floor.

Twenty 100-turn wire coils or loops 1 foot in diameter were embedded under each of the floor sections and were fed by tape recorders. The low frequency magnetic field they generated was picked up and amplified through handsets the visitors carried. The innovation in this system was the use of a large number of coils for each area to obtain an even distribution of the sound and not have sound spill over to another area.