Virtual reality may become more immersive now that the senses of touch, sight and hearing play a part in the experience. By using a sound wave system that projects haptic holograms into thin air, one can touch 3D virtual objects with bare hands.
Dr. Ben Long and his team at the University of Bristol, U.K. have developed a method of gathering haptic feedback for holographic visuals through the use of ultrasonic technology. The method alters the ultrasonic waves' modulation frequency.
The haptic feedback on shapes suspended in mid-air "eliminates the need for any attachment of actuators or contact with physical devices," researchers write. "The user perceives a discernible haptic shape when the corresponding acoustic interference pattern is generated above a precisely controlled two-dimensional phased array of ultrasound transducers."
In other words, the system uses sound waves in order to project haptic holograms. This allows one to touch sound or the 3D virtualization of sound waves. High-frequency sound waves are pulsed from tiny speakers, enabling one to have the "illusion" of touching and feeling an invisible object in thin air.
There's also a Leap Motion sensor that is used to track the position of one's hands. Though the tactile feeling of the object seems real, the sensation is actually produced by the sound that is hitting one's hands or the force of sound waves when it puts pressure to the skin.
"Touchable holograms, immersive virtual reality that you can feel and complex touchable controls in free space, are all possible ways of using this system," says Dr. Long. "In the future, people could feel holograms of objects that would not otherwise be touchable."
The team has already tested a number of shapes, such as spheres and pyramids. Long said that they seemed to be gently vibrating in space. While the level of detail may be limited when viewing a virtual object, the resolution of the projected image can be enhanced by using smaller speakers. Nevertheless, shapes don't have to be perfect in order to deliver an immersive experience.
