Disney tech lets users ‘feel’ 3D objects on a touchscreen

The technique relies on a specially developed algorithm that sends tiny vibrations through the display to let people feel the shallow bumps, ridges and edges of an object. The more pronounced the feature, the greater the vibration is needed to mimic its feel. "Our brain perceives the 3D bump on a surface mostly from information that it receives via skin stretching," said project leader Ivan Poupyrev, head of Disney's interaction research group in Pittsburgh. To validate the approach, the researchers used an electro-vibration based friction display to modulate the friction forces between the touch surface and the sliding finger. They first determined a psychophysical relationship between the voltage applied to the display and the subjective strength of friction forces, and then used this function to render friction forces directly proportional to the gradient of the surface being rendered. Dr Israr believes the technology will prove more flexible than existing systems used to give tactile feedback on touchscreens, which typically use a library of canned effects. "With our algorithm we do not have one or two effects, but a set of controls that make it possible to tune tactile effects to a specific visual artefact on the fly," he added.