Morphing materials could create shape-changing mobiles

Future smartphones could change shape to fit their users’ hands or purpose, according to new research.

Scientists at Bristol University have proposed developing shape-changing mobile computing devices or ‘morphees’ that could, for example, transform when a game is started to make it easier to play, or feature a three-dimensional keyboard that disappears when not being used.

The group have created six prototype shape-changing devices to test different materials and actuation systems that could be used to develop morphees, including dielectric electro active polymers (DEAPs) and shape memory alloys (SMAs).

‘In everyday life we interact with lots of different shapes that tells us how it is to be used, for example a door handle, a bottle mouth. And mobiles are just rectangular, they don’t fit to their functionality,’ research leader Dr Anne Roudaut told The Engineer.

‘There are a lot of different interesting materials that are growing in research labs that we are not especially aware of. We investigated how materials that change shape, expand or shrink when you apply a voltage.’

DEAPs are plastic materials that change shape when they are effectively squeezed by an electric field created between two electrodes, while SMAs are metallic materials that can be worked into a shape and then return to their original shape when heated.

The researchers identified ten properties that could be used to describe the shape resolution of devices, just as mobiles also have screen and touch resolutions, including curvature, stretchability and granularity (the density of points where movement occurs).

One prototype device made from a piece of paper covered in a DEAP had high granularity and flexibility but limited strength and curvature.

Another, made from pieces of wood sewn together with SMA wires, was found to be particularly successful because of its varied curvature and fast speed.

Roudaut said that the next challenges involved in developing morphees would include identifying which shapes were good for users and working on creating flexible component such as batteries.

The project is part of the EU-funded GHOST (generic, highly-organic shape-changing interfaces) programme that aims to design, develop, and evaluate prototype shape-changing computer interfaces.

Roudaut and her research co-leader Professor Sriram Subramanian will present their research to the CHI 2013 conference on human-computer interaction on Monday 29 April.