What does the metaverse smell like? Virtual reality passes the sniff test

Virtual reality can already create 3D immersive worlds using vision, audio and haptics, and now researchers are adding smell to the sensory experience.

Researchers from the University of Hong Kong created small, wearable, wireless VR interfaces with odour generators, allowing users to smell everything from rosemary, to pancake and even durian.

If you’ve ever wanted to get a whiff of the Sweet Sweet Kingdom in Mario Kart or a sniff of Suspicious Stew in Minecraft, the researchers say their devices could allow users to detect smells while playing video games.

Publishing in Nature Communications, the researchers outline two different wearable designs incorporating odour generators which work by heating a layer of scented food grade paraffin.

One design, a soft silicon device mounted on the upper lip with an adhesive embeds two odour generators.

A second alternative allows for up to nine different smells with the odour generators incorporated into a soft face mask.

The devices can be customised, with researchers demonstrating up to 30 different odour possibilities, including: ethanol, pineapple, grape, minty, rice, cream, gardenia, watermelon, vanilla, coffee milk, candy, coconut milk, coconut, milk, peach, pancake, orange, green tea, caramel, durian, lemon, strawberry, morning, ginger, clary sage, rosemary, lavender, clove, mojito and cake.

The researchers say future research could allow users to detect smells when playing video games, watching 4D films, and in virtual teaching environments.