"MODELING OF HUMAN FACTORS FOR VIRTUAL REALITY ENVIRONMENTS"

Abstract

3D Audio is a new technology in the world of Human-Computer Interface (HCI). It provides the capability to perceive the sound as it is in the real world, using 3D Audio system the user can decide upon the direction of the sound source (in terms of front or back, left or right, and above or below) and sound depth (in terms of near or far). As the Virtual Reality (VR) is the major trend in the world of HCI, incorporating the 3D Audio in the VR systems will enhance the user sense of Immersion. Sounds have characteristics associated with them. The brain uses physical cues to figure out sound characteristics. These physical cues then enable the brain to recognize what a sound is and where it is coming from. Positional audio technology deals with where. It tries to emulate physical cues so that the brain thinks sound is coming from a certain direction, a certain distance apart, in a certain sized room, and so forth. The cues, which have been widely accepted, are Source Depth or Range, Interaural Time Difference (ITD), Interaural Intensity Difference (IID), Head I Shadow, Pinna Response, Shoulder Echo, Head Motion, Early Echo Response, I Reverberation and Vision. This thesis is devoted to discussing and modeling of the 3D Audio and its !· physical localization cues. These cues are affected by the environmental conditions.

ITO is affected by the sound velocity, which is environment-dependent due to its affectance by the Temperature and Humidity. ITO is also affected by the Doppler's Effect, which depends on the sound source nature and user conditions. A proposed model for ITO is presented that considers all these factors and considers user head size and orientation. The IIO proposed model has been built as a varying filter that depends on head size, that is frequency-dependent, and in tum on the doppler that affects the sound pitch or frequency. The model also considers the extra distance between left , and right ear, which affects the degree of IID so the model includes it in the proposed

filter.

Range of sound source results from sound absorption, a proposed model has been built depending on a proposed air absorption frequency-dependent filter, and on absorption coefficients of different materials that is also frequency dependent.