Live sculptures and soft machines

Art has made little use of modern developments in smart materials and biomimetics, leaving a gap in artistic practices that we are starting to fill using electroactive polymer materials, also known as artificial muscles.

These materials are soft, malleable, and aesthetically lifelike. Most importantly, it is capable of lifelike movements, such as the swimming motion of a fish or the beating of a heart.

This project exploits artificial muscle actuation and sensing technologies to inject the breath of life into art through motion. And not just simple motion, but rather multi-degree of freedom deformations that can respond to external stimuli, including human  interaction in various forms. As a result, this active art is capable of considerably richer behaviours than most previous kinetic art.

Maori believe in wairua, or lifeforce, and the idea of an artwork potentially containing its own literal ‘lifeforce’ is new and exciting. Assessing the philosophical and spiritual ramifications to the Maori of having their art objects and patterns imbued with artificial life is an important part of this project.

This work also contributes to the advancement of a particular type of EAP^[?] technology known as dielectric elastomer actuators, whose performance is comparable to that of natural skeletal muscle, and better in some respects. It is focused on channelling that performance through self-sensing, control, and coordination of actuator arrays. These are key issues for many applications including lightweight and mobile robotics, as well as prosthetics. There is still much to learn about the emergent behaviour of multi-actuator artificial muscle systems, making this a fertile area for knowledge expansion.

The primary outcome of this project will be an active sculpture for public exhibition. The artwork, with complex motions that are to be partially controlled by human input, is intended to explore the boundaries of lifelike behavior and its interaction with people. The aim is to excite New  Zealanders about art through personal interaction and to engage with artists about the possibilities of using artificial muscles to add a new dimension to kinetic sculptures. We also believe that it would be interesting to observe how people of disparate ages and backgrounds engage with the art through action and reaction. For this reason, we foresee that it will be valuable to record the interactions between the art and the public during exhibitions.

Secondary to the creation of a piece of art, we believe that it will be beneficial to create and maintain a blog site for recording the project’s journey. We anticipate that through its comments function the blog will act as a forum where the artist can share and engage with other people about their experiences, experiments and results. More importantly, it serves as a different medium for the general public to participate in the project in both an active and passive manner.

The artist

Our lead  collaborator for this project is a young Maori artist, Katharine Ngatai a.k.a. KatyPie. She is a graduate from the Elam School of Fine Arts, specialising in kowhaiwhai design with stencilling and spray paint on wood, Perspex, resin and metals.

Funding

Phase I of this project is supported by the Smash Palace Fund, which is a partnership between Creative New Zealand and the Ministry of Research, Science and Technology. The fund has been designed to promote collaboration between New Zealand artists and scientists.

Kowhaiwhai

In Aotearoa, meeting houses are places of great symbolic significance to the Maori people. Each house personifies an ancestor, with the heke (rafters) of the meeting house representing that ancestor’s ribs.

The artwork inside the meeting house including whakairo (carving), tukutuku (panels), and kowhaiwhai (painted designs) illustrates the stories of the ancestors of the iwi (tribe) and different elements of nature.

It is the art of kowhaiwhai that interests our lead artist and drives her artistic inspiration. She wishes to focus on the natural depictions of kowhaiwhai (animals, fish, and plants) and extend them to her own original organic designs (see examples of traditional kowhaiwhai by downloading this word doc 91KB).

The koru, the basic design element of kowhaiwhai

Electro-active polymers

Polymers are generally lightweight, inexpensive and relatively pliable materials that can be configured into almost any conceivable shape. Polymers that shrink, expand or change shape when electrically stimulated are classified as electro-active polymers (EAP) and are also known as artificial muscles EAP are being actively studied for applications in bio-engineering and bio-robotics because of their potential for mimicking the movements of live beings.

One of the most important features of EAP is that they are capable of far larger and more complex motions than other smart materials. There is a wide range of different EAP, but we intend to focus on a particular type known as dielectric elastomers (DE) or electrostrictive polymer artificial muscle (EPAM). DE are solid-state, excel in terms of strain, speed, and energy density. Their electrically-induced strains can exceed 100%, that is over twice their original dimensions. Their performance is comparable, if not better in some respects, to that of natural skeletal muscle. DE are also functionally flexible as they can provide actuation, sensing and power generation in a single package.

When a high enough voltage is applied between the compliant electrodes, electrostatic forces produce large through-thickness compression and in-plane expansion of the dielectric elastomer.

(upper) Simulation of stages in the erection of a dielectric elastomer bending actuator, where changes in the dielectric elastomer membrane tension cause it to curl up. (lower) Testing of a dielectric elastomer bending actuator driven by a sinusoidal electrical signal with an amplitude of 2500 Volts.