How does the term “touchable hologram” sounds? Not so long ago the obvious answer would be a combination of “fantastic” and “impossible”. Scientists at Bristol University in collaboration with Bristol Interaction and Graphics (BIG) research group developed a device that may change these answers soon. UltraHaptics is based on the principle of acoustic radiation force, which means that several specially arranged ultrasonic transducers concentrate their emissions at a point somewhere in the air. The ultrasonic vibrations are projected through screen and cause tactile sensations on human's hand. Said in other words, tactile sensation is caused when all sound waves from all transducers meet at the same place and time.
Tom Carter, PhD student in the Department of Computer Science’s BIG research group, said: “Current systems with integrated interactive surfaces allow users to walk-up and use them with bare hands. Our goal was to integrate haptic feedback into these systems without sacrificing their simplicity and accessibility. To achieve this, we have designed a system with an ultrasound transducer array positioned beneath an acoustically transparent display. This arrangement allows the projection of focused ultrasound through the interactive surface and directly onto the users’ bare hands. By creating multiple simultaneous feedback points, and giving them individual tactile properties, users can receive localised feedback associated to their actions.”