Researchers at the University of California, San Diego report a breakthrough in technology that could pave the way for digital systems to record, store, edit and replay information in a dimension that goes beyond what we can see or hear: touch.
“Touch was largely bypassed by the digital revolution, except for touch-screen displays, because it seemed too difficult to replicate what analog haptic devices – or human touch – can produce,” said Deli Wang, a professor of Electrical and Computer Engineering (ECE) in UC San Diego’s Jacobs School of Engineering. “But think about it: being able to reproduce the sense of touch in connection with audio and visual information could create a new communications revolution.”
In addition to uses in health and medicine, the communication of touch signals could have far-reaching implications for education, social networking, e-commerce, robotics, gaming, and military applications, among others. The sensors and sensor arrays reported in the paper are also fully transparent (see optical image of transparent ZnO TFT sensor array at right), which makes it particularly interesting for touch-screen applications in mobile devices.
Digital replay, editing and manipulation of recorded touch events were demonstrated at various spatial and temporal resolutions. The researchers used an 8 × 8 active-matrix ZnO pressure sensor array, a data acquisition and processing system (sensor array reader circuit, computer, and actuator array driver circuit), and a semi-rigid 8 × 8 polymer diaphragm actuator array.
The ability to digitize the touch contact enables direct remote transfer of touch information, long-term memory storage, and replay at a later time. “In addition, with the ability to reproduce and change the feeling of touch with both temporal and spatial resolutions make it possible to produce synthesized touch,” said UC San Diego’s Wang. “It could create experiences that do not exist in nature, as we have done with computer-generated imagery and synthesized music.”
While Wang and his colleagues recognize that the touch revolution is still in its infancy, and human trials will probably be needed to calibrate the optimal actuator response needed to conform to the human perception of pressure strength, which depends on actuator displacement (amplitude), frequency, and how much time the actuator spends in its on- or off-state (duty cycle). Yet, say the researchers, there is every reason to believe that their experimental system, by adding an extra dimension to existing digital technologies, could extend the capabilities of modern information exchange.