augmentation techniques for efficient exploration in head-mounted display environments
Physical characteristics and constraints of today's head-mounted displays (HMDs) often impair interaction in immersive virtual environments (VEs). For instance, due to the limited field of view (FOV) subtended by the display units in front of the user's eyes more effort is required to explore a VE by head rotations than for exploration in the real world. In this paper we propose a combination of two augmentation techniques that have the potential to make exploration of VEs more efficient: (1) augmenting the geometric FOV (GFOV) used for rendering the VE, and (2) amplifying head rotations while the user changes her head orientation. In order to identify how much manipulation can be applied without users noticing, we conducted two psychophysical experiments in which we analyzed subjects' ability to discriminate between virtual and real head pitch and roll rotations while three different geometric FOVs were used. Our results show that the combination of both techniques has great potential to support efficient exploration of VEs. We found that virtual pitch and roll rotations can be amplified by 30\% and 44\% respectively, when the GFOV matches the subject's estimation of the most natural FOV. This leads to a possible reduction of the user's effort required to explore the VE using a combination of both techniques by approximately 25\%.
head-mounted displays geometric field of view head motion perception