Touch feedback has been advancing rapidly of recent time, and now we've gotten to the stage where ultrasound can be used to create entire 3D shapes to touch and feel in thin air.

We've seen 2D surfaces rendered in thin air using ultrasound before, but now researchers from the Bristol Interaction and Graphics group have used it to create entire 3D volumes. The researchers explain how it works:

The method uses ultrasound, which is focussed onto hands above the device and that can be felt. By focussing complex patterns of ultrasound, the air disturbances can be felt as floating 3D shapes... The system generates an invisible 3D shape that can be added to 3D displays to create something that can be seen and felt.

Don't believe them? The researchers show how it works by projecting their 3D volumes into oil in the video below, where the ultrasound can be seen as disturbances on the surface. It clearly really works. The research is published in ACM Transactions on Graphics and will be on display at SIGGRAPH Asia 2014 later this week.


The researchers reckon its first use in the real world will be in medicine, helping doctors feel things like tumors rendered from CT scans before they go anywhere near an operating theater. But who knows what other possibilities exist for such an amazing example of haptic feedback. [University of Bristol]