Presentation of odors is considered to be important as a means for giving a sense of presence. However, the basic odors have not been established to generate any kinds of odors by combining them, like the three primary colors in vision, the basic tastes in gustation. In order to present various kinds of odors, in general, it is necessary to prepare each corresponding odorant. In this research, an odor modulation method is proposed based on a cross-modal effect between olfaction and thermal sensation, which might be able to decrease the number of odorants used to generate odors presented to the user. The experimental results are reported to show that sensation of odors can be modulated by presenting warm/cool air with the odors even if the same odors are presented to the subjects.

We present fARFEEL, a remote communication system that provides visuo-haptic feedback allows a local user to feel touching distant objects. The system allows the local and remote users to communicate by using the projected virtual hand (VH) for the agency of his/her own hands. The necessary haptic information is provided to the non-manipulating hand of the local user that does not bother the manipulation of the projected VH. We also introduce the possible visual stimulus that could potentially provide the sense of the body ownership over the projected VH.

The smelling screen is a new olfactory display that can generate a localized odor distribution on a two-dimensional display screen. The generated odor distribution is as if an odor source had been placed on the screen, and leads the user to perceive the odor as emanating from a specific region of the screen. The position of this virtual odor source can be shifted to an arbitrary position on the screen. The user can freely move his/her head to sniff at various locations on the screen, and can experience realistic changes in the odor intensity with respect to the sniffing location.

We propose a new olfactory display system that can generate an odor distribution on a two-dimensional display screen. The proposed system has four fans on the four corners of the screen. The airflows that are generated by these fans collide multiple times to create an airflow that is directed towards the user from a certain position on the screen. By introducing odor vapor into the airflows, the odor distribution is as if an odor source had been placed onto the screen. The generated odor distribution leads the user to perceive the odor as emanating from a specific region of the screen. The position of this virtual odor source can be shifted to an arbitrary position on the screen by adjusting the balance of the airflows from the four fans. Most users do not immediately notice the odor presentation mechanism of the proposed olfactory display system because the airflow and perceived odor come from the display screen rather than the fans. The airflow velocity can even be set below the threshold for airflow sensation, such that the odor alone is perceived by the user. We present experimental results that show the airflow field and odor distribution that are generated by the proposed system. We also report sensory test results to show how the generated odor distribution is perceived by the user and the issues that must be considered in odor presentation.

A new olfactory display that can present a virtual odor source at an arbitrary position on a two-dimensional screen is proposed in this paper. The proposed device can give a sensation that an odor is emanating from a certain position on the screen. Fans are placed at the four corners of the screen. The airflows generated by the fans are deflected multiple times by making them collide with each other, and are finally directed toward the user from the position of a virtual odor source on the screen. By introducing odor vapor into the airflows, the odor is spread from the virtual odor source toward the user. The position of the virtual odor source can be shifted to an arbitrary position on the screen by adjusting the balance of the airflows from the four fans. The user can freely move his/her head and sniff at various locations. Potential applications of the proposed device include digital signage, video games, and exhibitions in museums. The result of odor-distribution measurement is presented here to show the validity of the device design.

A new device has been developed for generating airflow field and odor-concentration distribution in a real environment for presenting to the user. This device is called a multi-sensorial field (MSF) display. When two fans are placed facing each other, the airflows generated by them collide with each other and are radially deflected on a plane perpendicular to the original airflow direction. By utilizing the deflected airflow, the MSF display can present the airflow blowing from the front to the user without placing fans in front of the user. The directivity of the airflow deflection can be controlled by placing nozzles on the fans to adjust the cross-sectional shape of the airflow jets coming from the fans. The MSF display can also generate odor-concentration distribution in a real environment by introducing odor vapors into the airflow generated by the fans. The user can freely move his/her head and sniff at various locations in the generated odor distribution. The results of preliminary sensory tests are presented to show the potential of the MSF display.

This article describes the investigations on the effect of airflow on the perception of odors presented by an olfactory display device. A clear sensation of the direction to an odor source can be given to the user of the olfactory display when the air currents are provided to the user's face by using fans. When the air currents are not provided, the user feels as if the source is placed nearby. We hypothesize that this sensation is caused by the upward air currents generated by our body temperature. When there is no wind, only the odors from nearby sources are brought to our noses by the upward air currents. The result of a sensory test shows that the perceived location of an odor source changes with the airflow presented to the panelist. Providing airflow together with odors is thus promising to reproduce complicated situations that cannot be reproduced by olfactory stimulation alone.

This article describes the experiments on an interactive application of an olfactory display system into which computational fluid dynamics (CFD) simulation is incorporated. In the proposed system, the olfactory display is used to add special effects to movies and virtual reality systems by releasing odors relevant to the scenes shown on the computer screen. To provide high-presence olfactory stimuli to the users, a model of the environment shown in the scene is provided to a CFD solver. The airflow field in the environment and the dispersal of odor molecules from their source are then calculated. An odor blender is used to generate the odor with the concentration determined based on the calculated odor distribution. In the experiments, a virtual room was presented on a PC monitor, and the panel were asked to stroll in the room to find an odor source. The results showed the effectiveness of the CFD simulation in reproducing the spatial distribution of the odor in the virtual space.

The results of our current multidisciplinary research efforts on the development of an olfactory display system are demonstrated. To present odors with a vivid sense of reality, we propose to use computational fluid dynamics (CFD) simulation in conjunction with the olfactory display system. In this demonstration, an odor is released with a movie clip using the olfactory display. A CFD solver is employed to calculate the turbulent airflow field in the given environment and diffusion/advection of odor molecules from their source. The olfactory display system generates an odor with the concentration determined by the calculated odor distribution. The user is assumed to be a small animal slowly walking through a virtual room, and experiences the spread of the odor in the room.