ShapeTex

Introduction
Research in smart textiles and garments has mostly focused on the integration of sensing technologies. In order to make garments that are truly interactive it is necessary to develop technologies for actuating smart garments and textiles. ShapeTex is a thermal shape changing fabric for application on smart textiles. ShapeTex has a three layer structure: a copper/aluminum layer with certain heating pattern; a fabric layer as the substrate; an ultra high molecular weight layer as the transformation and protection layer. The principle by which actuation is achieved is based on the principle of laminate thermal expansion: The thermal coefficient of polythene tape and fabric are very different. When a current is put through the metal layer, ShapeTex will be heated and deform. The speed of transformation depends on the current, the overall weight of the piece, and the thickness of the polythene tape.

Why we made this?
In shape changing interfaces users can provide input by modifying the shape of these devices or can receive output through some form of actuation. However, research on shape changing interfaces with very few exceptions has considered the use of actuation on garments.

Traditional wearable shape-changing interfaces rely on external mechanism such as motors, shape memory alloy and soft robotics to provide the force for shape transformation. These actuation routes hinder the flexibility, efficiency and are difficult to conceal but also hard to control. Furthermore the fabrication of such constructions requires still a lot of handwork, which makes it harder for designers to prototype such solutions and use them in their designs. To improve the performance and to lower the threshold for prototyping wearable shape-changing interfaces, new mechanisms are needed that will provide unobtrusiveness and wearability sufficient for their integration in smart garments.

How can it help fashion designers expressing their creativity?
From an aesthetics perspective, we can make a lot of improvements on the metal pattern to make it less technical-looking. For example inspired by paintings of Mondrian we made a grid pattern that looks more rhythmic and abstract, but not strictly geometrical. Alternatively, a nature inspired pattern e.g. as leaves can be created to decorate a textile or garment. Although it does influence the engineering performance to a degree, applying different patterns is justified given the aesthetic qualities and freedom it offers to designers.

From an interaction design perspective, the pattern can create a complete interactive system comprising of a fabric circuit board with input (copper or aluminum foil as capacity sensor or NFC coil), processor (SMD microcontrollers soldered on the pattern) and the output (ShapeTex as the actuator). This structure makes the fabric circuit board seamlessly attached with aesthetical patterns.

We cooperated with a few fashion designers in this project by helping them making their own shape changing design. The designs have been exhibited in Eindhoven and Amsterdam and got a lot of interest from other fashion designers. We are now funded by the EU WEAR Sustain foundation and trying to show it in Dutch Design Week for more attention.