A face mask designed to enhance virtual reality can release various smells to make the simulation more immersive. It could even be used to mimic the odour of absent loved ones during virtual meetings, say its creators.
The senses of sight, sound and touch are all commonly catered for by virtual reality systems, but smell isn’t usually despite its important role in day-to-day life and in forming and recalling memories.
Xinge Yu at City University of Hong Kong says earlier smell generators were large, “clumsy” devices, which leaked odour throughout a large area and were sluggish to switch from scent to scent.
His team has created two devices that can release odours on demand. One is a flexible patch around 5 centimetres long mounted on the upper lip containing two cells, each with the ability to release one scent. The other is a face mask with a grid of nine different smells, which can also be combined to create other odours.
Each device is controlled by a small chip that communicates with computers wirelessly via Bluetooth to coordinate the release of smells as the wearer nears an odorous object in VR.
The smells are created by liquid perfumes added to containers of paraffin. When a smell is needed, the cell is heated to 50°C (122°F) with a small radiator. Because both devices are close to the nose, wearers can detect the scents within 1.5 seconds of them being switched on.
In an experiment with the face mask, 11 volunteers were able to detect different odours, including mint, jasmine, lavender and pineapple, with an average success rate of 93 per cent.
Yu says the system can make virtual reality more convincing, but could also be used to make people in different places feel closer to each other.
“By wearing the olfaction system, children could sense their absent families’ odour, and separate couples could feel each other by smelling their odours,” he says. “In terms of entertainment, users could experience various outdoor environments with different nature smells at home by VR. We think bad smells can be used as easily as pleasant smells.”