New technology developed at the Intelligent Material Systems Lab at Saarland University and at ZeMA (Center for Mechatronics and Automation Technology) in Saarbrucken enables buttons to appear and disappear at any point on the touchscreen of an IT device.
By generating vibrations, pulses or individual jolts that are felt by the user’s fingertip, the screen can guide the user’s finger to a virtual button at any required location on the display. This functionality opens up a whole range of options for computer games, internet searches and for satnav devices.
The material the film is made from is known as a dielectric elastomer.
The engineers in Seelecke’s team print an electrically conducting layer onto an extremely thin polymer membrane on to which they apply an electric voltage. Because the film is ‘electroactive’, it contracts in one direction and expands in the other when a voltage is applied to it.
"As a result of electrostatic attractive forces, the polymer film can, for example, be squeezed vertically, causing it to expand outwards," explained Steffen Hau, a PhD engineer working in Seelecke’s team.
If the researchers alter the electric field, the film responds by performing complex choreographies and produces tactile signals that range from high-frequency oscillations to pulsing motions like a heart beat or continuous variable flexing motions.