Dielectric elastomer stack actuators (DESA) promise breakthrough functionality in user interfaces by enabling freely
programmable surfaces with various shapes. Besides the fundamental advantages of this technology, like comparatively
low energy consumption, it is well known that these actuators can be used as sensors simultaneously.
The work we present in this paper is focused on the implementation of a DEA-based tactile display into a mobile device.
The generation of the driving voltage of up to 1.1 kV out of a common rechargeable battery and the implementation of
the sensor functionality are the most challenging tasks.
To realize a large range of tactile experiences, both static and dynamic driving voltages are required. We present a
structure combining different step-up topologies to realize the driving unit. The final circuitry complies with typical
requirements for mobile devices, like small size, low weight, high efficiency and low costs.
The sensing functionality has to be realized for different actuator elements regardless of their actual state. An additional
sensing layer on top or within the actuators would cause a higher fabrication effort and additional interconnections.
Therefore, we developed a high voltage compatible sensing system. The circuitry allows sensing of user input at every
Both circuits are implemented into a handheld-like device.
Dielectric polymer actuators promise to revolutionize user interfaces by enabling surface actuators that can change
surface shape and give tactile feedback from a thin layer. We have realized a programmable surface actuator, based on
non-pre-stretched silicone, which is capable of realizing large freeform surface deformations from relatively thin layers,
while maintaining very good control over the shape of the actuated surface. Moreover, the actuator setup allows the use
of a thin, stiff top layer, which addresses friction and stickiness problems commonly associated with using soft
elastomers in tactile displays. Out-of-plane deformations exceeding 300 μm are possible, facilitating 'tactile exploration'
of the actuated shapes.