Engineering: Smelling the flowers in virtual reality(Nature Communications)

A small, wearable virtual reality (VR) interface that allows users to smell several different odors — including rosemary, mojito, pancake, and durian — is reported in a Nature Communications paper. The devices can quickly and accurately generate odors in a localized area and connect wirelessly to VR worlds for an immersive and more realistic user experience. Future research could allow users to detect smells when playing video games, 4D films, and in virtual teaching environments, the authors suggest.

Human-machine interface systems have previously been developed to simulate vision, sound, and touch in VR, but designing a system for smell has been challenging. Current smell interface designs have bulky formats using bottles of liquid perfume or wired, rigid VR headsets that limit their practicality. Wearable odor generators that are lightweight, flexible, wireless, and equipped with a wide selection of odor types and programmable scent intensities have yet to be created.

Xinge Yu, Yuhang Li and colleagues designed two wearable formats of the wireless smelling interface. Using millimeter-scale odor generators, the first format is directly attached to the skin under the nose with two odor options, and the second is a soft mask capable of generating nine different odors. The authors demonstrate its customizability with a selection of 30 different odor types — including pineapple, ginger, green tea, caramel, and candy. The tiny odor generators contain scented paraffin wax, which can be heated to release specific odors quickly (in as little as 1.44 seconds) and accurately in a localised area.

The authors suggest several applications for the research, such as for delivering scent messages as an alternative communication method, triggering emotional memories, and enhancing user interaction in VR worlds.