Walking does not Diminish Localizability of Vibrotactile Feedback on the Waist

Individuals who lack tactile and/or proprioceptive sensations in their lower limbs commonly report postural and locomotive imbalance. To mitigate imbalance, haptic feedback has been implemented using devices that employ external sensors and waist-worn actuators for sensory augmentation. Analyses of the effectiveness of these devices have primarily focused on balance outcomes and generally disregard the potential effect of the user's varying activities or anthropometric data on their perception of the haptic feedback. Since motor activity can influence haptic perception, we investigate vibrotactile cue localizability in a waist-worn haptic device for two conditions, standing and walking on a treadmill at a self-selected speed. In this preliminary study, ten participants without sensorimotor deficits wore a waistband equipped with seven vibrotactile actuators. Vibrotactile cues were played at randomized locations during standing and walking, and participants reported the perceived stimulation location. In addition, we recorded relevant anthropometric data for each participant. In both standing and walking conditions, participants correctly localized 51% of the vibrotactile cues on average. When considering zonal accuracy, or localization within one vibrotactor position, participants, on average, achieved an accuracy of 91 % in standing and 90% in walking.