Recording and replaying human touch: the next user-interface revolution?
September 9, 2013
“Touch was largely bypassed by the digital revolution, except for touch-screen displays, because it seemed too difficult to replicate what analog haptic [touch] devices can produce,” said Deli Wang, a professor of Electrical and Computer Engineering (ECE) in UC San Diego’s Jacobs School of Engineering and senior author of a Nature Scientific Reports paper (open access) on this research.
“Being able to reproduce the sense of touch in connection with audio and visual information could create a new communications revolution.
“Communication of touch signals could have far-reaching implications for health and medicine, education, social networking, e-commerce, robotics, gaming, and military applications, among others,” said Wang.
The sensors and sensor arrays reported in the paper are also fully transparent, making them useful for future touch-screen applications, especially in mobile devices.
Prototype touch recording/playback system
The researchers developed a prototype system for electronic recording of touch contact and pressure using an an 8 × 8 active-matrix pressure sensor array made of transparent zinc-oxide (ZnO) thin-film transistors (TFTs).
The touch recording data was then sent to a data acquisition and processing system and from there to a tactile feedback display, which used an 8 × 8 array of diaphragm actuators made of an acrylic-based dielectric elastomer with the structure of an interpenetrating polymer network (IPN). The polymer actuators’ force and level of displacement are modulated by adjusting both the voltage and charging time.
Human trials will probably be needed to calibrate the optimal actuator response needed to conform to the human perception of pressure strength, said Wang.
Creating synthetic touch experiences
“One of the critical challenges in developing touch systems is that the sensation is not one thing. It can involve the feeling of physical contact, force or pressure, hot and cold, texture and deformation, moisture or dryness, and pain or itching. It makes it very difficult to fully record and reproduce the sense of touch.”
In addition to simply playing back touch, the touch data can be stored in memory and replayed at a later time or sent to other users. It is also possible to change the feeling of touch, or even produce synthesized touch by varying temporal or spatial resolutions,” said Wang. “It could create experiences that do not exist in nature.”
The project is partially supported by a Qualcomm Innovation Fellowship.