Next frontier of virtual reality: Wireless scent generators create “flawless 4D worlds”

07 Jun 2023 --- Researchers are investigating how to introduce an untapped dimension of augmented reality – into the realm of scent. Integrating smell into an olfactory virtual reality that mimics the real world may potentially revolutionize fragrance sampling, entertainment, education and human-machine interfaces.

Consider the potential of sampling perfume in an accentuated VR setup for the metaverse. Working toward this, researchers writing in Nature have piloted their concept called “skin-interfaced olfactory feedback systems,” which are small devices that can generate different scents and integrate them into the VR world.

“Demonstrations in 4D movie watching, smell message delivery, medical treatment, human emotion control and VR/AR-based online teaching prove the great potential of the soft olfaction interface in various practical applications, including entertainment, education, human machine interfaces and so on,” they suggest.

Olfactory virtual reality
The piloted “skin-interfaced olfactory feedback systems” can be wirelessly controlled using a computer program, providing users with the ability to smell different scents as they navigate the virtual environment.

Bringing smells to virtual spaces is deemed the next frontier of augmented reality (Image credit: Nature).To ensure optimal performance, the scientists carefully selected materials, designed the devices with precision and managed their power usage.

This resulted in odor generators that have excellent response rates, precise control over odor concentration, long-lasting continuous operation, mechanical and electrical stability and low power consumption.

The researchers integrated the device into a special face mask with nine different odor options, which triggers the controlled release of a smell by heating up its temperature.

They highlight that the potential applications for this technology are vast and varied. This was demonstrated in several scenarios.

For instance, the researchers evidenced how users could watch 4D movies that not only offer visual and auditory experiences but also incorporate relevant scents. Additionally, the technology enables the delivery of “smell messages,” where scents can be used as a means of communication.

The medical field could also benefit from this innovation, conclude the researchers. Olfactory VR applications could provide a new way to deliver certain medical treatments or even help individuals control their emotions in therapeutic settings.

Moreover, the education sector could utilize the technology for immersive online teaching experiences, enhancing student engagement and understanding.

The study investigated two types of olfactory generating devices, one stick-on version that attaches to the upper lip and one mask-based model (Image credit: Nature).Mechanisms of odor generation
The ultimate goal of the researchers is to create a personalized and localized odorous environment, while decreasing the long response time of the device switching between different smells.

The study investigates the best materials and different device designs to create wirelessly controlled odor generators in thin, soft and flexible sheets of electronics. Emphasis was put on comfort and wearability, making it applicable to various uses.

Users in the study were presented with a small-scale olfaction interface that can be stuck onto a person’s upper lip, which could switch between two different basic odor types.

The participants could also experience another version of the interface, which was integrated into a face mask that created a personalized, localized odorous environment. This version integrated nine different original odors.

New immersive experiences
By training visually or auditory impaired users to link some odors to specific events – such as lavender odor with walking outside, pineapple odor with having lunch, or green tea odor and teatime – the researchers found that users could simultaneously react to the mechanically released odor and another stimulus.

One example is the scenario of an immersive 4D movie watching experience, where the subject in the movie is smelling a flower as she approaches it.

While this is happening, the heating temperature of the odor generators simultaneously rises in real time, coinciding with the shrinking distance between the odor source and the subject’s nose. This releases a growing fragrance of roses for users in the real world.

While there are currently wearable odor generators that atomize perfume into tiny droplets that are blown out, the researchers state these are limited in their functionalities.

Olfaction exerts both physiological and psychological influences, which adds a new dimension to virtual experiences (Image credit: Nature).“The clumsy working mechanics, fully rigid package with bulky bottles of liquid perfumes, and special maintenance requirements have indicated the inherent defects of these wearable odor generators for realizing high-channel odor generators in a miniaturized, lightweight and flexible format,” highlight the researchers.

Emotions of scent
Equally important to traditional visual, auditory and tactile sensations, olfaction exerts both physiological and psychological influences on humans.

Fragrance house Givaudan recently kickstarted a project that uses neuroscience and AI to translate scent profiles into color patterns for better fragrance branding. The company aims to broaden its “feel colors, smell emotions” approach in perfumery.

Last December, fragrance house Firmenich introduced a range of fragrances branded Focus, powered by EmotiCODE. The scents are designed to give consumers the benefit of improved focus and help them get into a state of flow.

Next to the exploration of consumers’ psychological perceptions of olfactory stimuli, researchers at IFF are examining emotional triggers linked to textures in personal care and beauty formulas.

By Benjamin Ferrer