The key to a sense of touch in VR might be sound, ironically – a team working out of the University of Bristol in the UK (via New Scientist) have worked out an improved version of haptic tech that can use high-frequency sound emitters to mimic the effect of touching a physical object, without any physical object present.

Researcher Ben Long and his team at the university had already created a system by which sound could produce a sensation of physical touch, using speakers that produce waves that impact a user’s skin enough to exert a sense of pressure.

To make that workable with VR, the team incorporated a Leap Motion controller, the gesture control device crowdfunded by a startup in 2010 and shipped in 2013. The controller can help determine the position of a user’s hands relative to a virtual image displayed in a VR environment, say one produced by an Oculus Rift headset, and provide an appropriate tactile response when they interact with said object.

Just like with digital and printed images, there are issues around resolution when projecting a shape in this manner – virtual objects feel like they’re vibrating slightly in mid-air, for instance, and high detail isn’t yet possible. Plans are in place for use of speaker arrays that include smaller individual units, which working in concert should mean higher resolution, the same way more pixels packed into less space produces higher-resolution digital graphics.

True immersion in any VR experience will require this kind of tactile interaction, so the tech is exciting to say the least. Oculus VR is on record as saying controllers are still the key ingredient missing from virtual reality, and recently suggested that development of an appropriate input method might be the last hurdle towards pinning down a consumer ship date.