How Much Redirection Is Too Much? The Emergence of a Preliminary Tolerability Boundary as a Key Protocol Criterion

Redirected walking (RDW) enables users to explore virtual environments larger than the physical tracking space by subtly altering the mapping between virtual and physical trajectories. While RDW is widely recognized for physical training, rehabilitation, and cognitive studies, understanding human perception and implementation parameters remains critical. Prior RDW research has primarily focused on perceptual detection thresholds, often classifying perceptible redirection as undesirable. This pilot study investigates how much redirection users can tolerate when they are explicitly aware of the manipulation. Using an artificial potential field (APF)-based redirected walking (APF-RDW) algorithm, six participants completed five virtual walking paths under three redirection strengths (move rates of 30, 50, and 75). Quantitative measures included task completion time, walking speed, force-vector magnitude, and post-study evaluations of redirection perceptibility, ease of navigation, and discomfort. As redirection strength increased, task completion times lengthened, walking speeds decreased, and redirection became more perceptible. Participants also reported greater navigation difficulty and increased discomfort. Moderate redirection remained acceptable despite increased user awareness, whereas the highest redirection level caused a sharp decline in user experience. These findings suggest but do not identify a tolerability threshold, highlighting tolerability as a practical framework for developing RDW methods and customizing protocols to subject-specific criteria.