Soft, miniaturized, wireless olfactory interface for virtual reality

Abstract

Recent advances in virtual reality (VR) technologies accelerate the creation of a flawless 3D virtual world to provide frontier social platform for human. Equally important to traditional visual, auditory and tactile sensations, olfaction exerts both physiological and psychological influences on humans. Here, we report a concept of skin-interfaced olfactory feedback systems with wirelessly, programmable capabilities based on arrays of flexible and miniaturized odor generators (OGs) for olfactory VR applications. By optimizing the materials selection, design layout, and power management, the OGs exhibit outstanding device performance in various aspects, from response rate, to odor concentration control, to long-term continuous operation, to high mechanical/electrical stability and to low power consumption. Representative 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.

Skin-Integrated Wireless Odor Message Delivery Electronics for the Deaf-blind

“…Here, to realize a fast response time in release odor, 45 °C had been chosen for the standby heating temperature, as it is highly close to the melting point of the wax, which is around 50 °C. As a consequence of a relatively longer systemic delay compared to our previously reported OGs, more significant thermal fluctuations during the stabilizing state resulted due to the extended high- and low-power switching time.…”

“…Lastly, to reveal the relationship between the smell-generating time and the paraffin wax mass, the duration of odor release of eight different odorants with different paraffin wax masses (2.5, 10, and 20 mg) was recorded at the heating temperature of 60 °C. In this experiment, although a higher portion for the perfume increased the smell-generating time, the blend ratio between the wax and perfume was optimized to be 10:1 among 10:1, 10:2, and 10:3. This is because, as shown in Figure L, eight whole smell types with 20 mg of paraffin wax (wax:perfume = 10:1) could be generated for more than 3 h, including error ranges which are sufficient for covering the optimum operation time.…”

“…Then, the operational stability and repeatability of the OG were proved through the cyclic test for over 20 h. Through the operational performance tests and electrical power and structural dimension optimization of the OG, the superiority of the reporting OG over the reported or commercialized olfaction interfaces was certainly revealed (Table S1). ,− Compared to the reported smell-generating devices, the OG was apparently lightweight, small, wirelessly operated, and flexible, making it suitable for skin-integrated applications. At the same time, it presented a relatively rapid response time and a wide variety of odor options (24 in total) for achieving fast reactions against stimuli and high smell-generating efficiency.…”

“…As the odor generation unit of the whole system, OGs could accurately release or shut down various odors by melting or solidifying odorous wax in a short time (∼0.6 s), in which the printed electrode serves as heaters and the mechanical actuators act as the active cooling system. Compared to the OGs reported by our group very recently, the OGs reported here adopt a simplified structure to realize a smaller overall size (length × width × height of 11 mm × 10 mm × 2.2 mm), where the heating electrode also serves as a temperature sensor by continuously monitoring its resistance variation while the previously reported OGs managed thermistor as A thermal sensor and heater separately. Subsequently, the fabricating process was streamlined; meanwhile, the size and weight of the OG unit were reduced.…”

Virtual, augmented, and mixed reality as a versatile tool in food consumer behavior evaluation: Recent advances in aroma, taste, and texture incorporation

“…Recently, a wireless skin-interfaced olfactory feedback system with small flexible odor generators has been developed. The device is simple to use, long-lasting, stable, consumes little power, and has controllability on odor concentration (Liu et al, 2023). For virtual taste incorporation in humans, a default setup consisting of a computer, control system, and tongue interface is required (Ullah et al, 2022).…”