Looking down with the head up: improving walking in VR and VST-AR with increased downward field of view

Abstract

Head-Mounted Displays (HMDs) allow users to move freely in virtual environments and interact with various objects. However, existing HMDs have a limited downward Field of View (FOV), restricting visibility of the feet and nearby virtual objects unless users tilt their heads downward. This limitation complicates walking in HMDs, leading to increased difficulty and apprehension, and constrains interaction with virtual objects. In this study, we investigate how the area near the user’s body affects presence, walking, and interactions such as avoiding or stepping over virtual objects, using an HMD with an expanded downward FOV. We also examined whether these effects were present in both Virtual Reality (VR) and Video See-Through Augmented Reality (VST-AR), which typically has narrower FOVs and higher latencies than VR. When the downward FOV was expanded, users could walk and avoid virtual objects more easily without needing to tilt their heads downward. Notably, participants moved their feet significantly while avoiding the virtual objects by stepping over them. Exploratory analyses further suggested that the increased downward FOV may enhance the realism and the perceived three-dimensionality of the virtual objects.