Investigating the Use of Movement Kinematics to Assess Perceptual Ambiguity in Virtual Reality

With the emergence of 3D direct-selection interfaces in virtual reality (VR) displays, specialized metrics may be needed to assess the efficiency of these complex interactions. Kinematic movement trajectory analysis, an established technique in experimental psychology, may provide a useful framework for quantifying meaningful patterns of user interaction using the 3D position data recorded by most VR displays. We explored this possibility by investigating the effectiveness of a kinematic approach for identifying ambiguous interface elements in VR by detecting movements initiated toward incorrect target locations (termed “misfires”). Twenty-three participants selected 96 target objects of varying perceptual ambiguity presented in a simple VR environment with limited depth cues. Movement trajectories were recorded and evaluated using a-priori criteria to identify discontinuities consistent with misfire movements. Misfires were observed on 31.6% of trials and occurred significantly more often for movements to perceptually ambiguous targets. The findings of this study suggest that kinematic measures may be useful for quantifying patterns of user interaction in direct-selection VR interfaces.