Olfactory display for the treadport active wind tunnel

This thesis discusses the development of an olfactory display for the University of Utah TreadPort Virtual Environment (UUTVE). The goal of the UUTVE is to create a virtual environment that is as life like as possible by communicating to the user as many of the sensations felt in moving around in real the world as possible, while staying within the confines of the virtual environment's workspace. The UUTVE has a visual display, auditory display, a locomotion interface and wind display. With the wind display, it is possible to create an effective olfactory display that does not have some of the limitations associated with many of the current olfactory displays. The inclusion of olfactory information in virtual environments is becoming increasingly common as the effects of including an olfactory display show an increase in user presence. The development of the olfactory display for the UUTVE includes the following components: the physical apparatus for injecting scent particles into the air stream, the development of a Computational Fluid Dynamics (CFD) model with which to control the concentration of scent being sensed by the user, and user studies to verify the model and show as proof of concept that the wind tunnel can be used to create an olfactory display. The physical apparatus of the display consists of air atomizing nozzles, solenoids for controlling when the scents are released, containers for holding the scents and a pressurized air tank used to provide the required air to make the nozzles work. CFD is used model the wind flow through the TPAWT. The model of the wind flow is used to simulate how particles advect in the wind tunnel. These particle dispersion simulations are then used to create a piecewise model that is able to predict the scent's concentration behavior as the odor flows through the wind tunnel. The user studies show that the scent delivery system is able to display an odor to a person standing in the TPAWT. The studies also provided a way to measure the time it takes for a person to recognize an odor after it has been released into the air stream, and also the time it takes for a user to recognize that the odor is no longer present.