# AIR & WATER

Ping-Pong balls are suspended by 12 air streams via Bernoulli’s principle. The balls interact with each other in a chaotic fashion, each of them affecting the air stream around its neighbors. The behavior of the system can be adjusted by varying the number of balls and the air velocity. At certain settings the balls move gently toward and away from each other in a kind of dance. At other settings the balls jump over each other, seemingly juggled by invisible hands.

Unlike a regular kaleidoscope in which the three mirrors form a triangular prism, the mirrors in the polyhedral kaleidoscope form a truncated triangular pyramid. This results in the replicated images no longer being coplanar (as in a regular kaleidoscope), but rather meeting each other at an angle. In this version of the polyhedral kaleidoscope the angles are calculated to create a virtual icosahedron—one of the five Platonic solids—formed by 20 equilateral triangles.

Ping-Pong balls are carried aloft by three geysers on which they balance and spin . When a ball falls out of one geyser, the sloped mesh surface encourages it to roll counter-clockwise to the next geyser. When a ball enters a geyser, it interrupts the flow of water, thus releasing the geyser’s current ball, which then moves on to the next geyser. This action continues around in a circuit of endless feedback so that each ball is affected by its own previous actions. At times the balls seem to be fighting over access to the geysers, thus the name “My Turn”. The behavior of the system can be adjusted by varying the number of balls, and the height and angle of the geysers.

Ping-Pong balls are supported by 12 geysers via Bernoulli's principle. The geysers are spaced so that the balls are somewhat stable in a single geyser, but can also be drawn over to the neighboring geyser at random intervals. The balls also interact with each other, trading places, spinning around each other, or knocking each other out of the geyser. The behavior of the system can be adjusted by varying the number of balls, and the height and angle of the geysers.

The direction and velocity of the water changes according to the fish's location. A micro-controller uses data from multiple light sensors to determine the fish's position, and adjusts the water-control gates accordingly.