Figure 2. Morpho Tower, 2006.

Figure 3. Morpho Tower/ Two Standing Spirals, 2007.

information from the environment or living beings through physical devices. However, it can be stated that there has been little work on expression through flexible changes of the surface texture controlled by a computer.

The goal of my project is to create organic shape-changing art forms and figures whose 3D form, surface structure, and color change dynamically and lively as if to reflect echoes of environmental music, light, and human communication. To create such 3D organic forms and surfaces, in 2000 I started using ferrofluid in my interactive art project Protrude, Flow (see Figure 1).

Ferrofluids, the shape-changing material used in my works, were invented in the late 1960s in the

Apollo Program of the U.S. National Aeronautics and Space Administration (NASA) and are known to be used for forming liquid seals and in electronic devices for computers, audiovisual equipment, and other industrial applications. Recently, they have been employed in medical research.

Ferrofluids, which appear as a black fluid, are prepared by dissolving nanoscale ferromagnetic particles in a solvent such as water or oil and remain strongly magnetic even in a fluid condition. Therefore, they are more flexibly transformable as compared to iron sand. It is well known that ferrofluids form spikes along magnetic field lines when the magnetic surface force exceeds the stabilizing effects of the fluid weight and surface tension [ 1]. In my work, organic shapes are produced by these spikes under a magnetic field that is controlled by electromagnets. Sensing technology and computers are used to make the fluid change its shape according to environmental information. The transformation of the shape and rhythm of the movement are important aspects of the work.

My first project, Protrude, Flow, used six electromagnets. In this work, the electromagnets sometimes prevented people from viewing the moving liquid. To solve this problem and to simplify the work, I discovered a new technique called ferrofluid sculpture. This technique enables artists to create more dynamic sculptures with fluid materials. One electromagnet is used, with an extended iron core that is sculpted into a particular shape. The ferrofluid covers the sculpted surface of the 3D iron shape. The movement of the spikes in the fluid is controlled dynamically on the surface by adjusting the power of the electromagnet.

The Morpho Tower series in 2006 was my first realization of a ferrofluid sculpture. Figure 2 shows the spiral tower covered with numerous ferrofluid spikes. A spiral tower is positioned on a plate that holds the ferrofluid. When the magnetic field around the tower is strengthened, spikes of ferrofluid are generated in the bottom plate and move upward, trembling and rotating around the edge of the iron spiral [ 2].

The movement of the spikes in the fluid is controlled on the surface by adjusting the power of the electromagnet. The shape of the iron body is designed to be helical so the fluid can move to the top of the helical tower when the magnetic field is sufficiently strong. The surface of the tower responds dynamically to its magnetic environment. When there is no magnetic field, the tower appears