Effects of a Person-Following Light-Touch Device During Overground Walking With Visual Perturbations in a Virtual Reality Environment

Background: Proprioceptive feedback represents an alternative sensory channel that may be stabilizing in both overground gait in a virtual environment (VE), as well as when using an assistive device for overground gait. A person-following robot could potentially provide more useful proprioceptive feedback as compared to conventional assistive devices, such as a cane, as the person could maintain continuous contact with the environment with a reduced cognitive load. Methods: Using a light touch support paradigm, we explore whether a person-following robot could act as a proprioceptive reference point to stabilize overground gait. Twelve healthy subjects completed ten passes across an instrumented walkway in various conditions. These conditions tested the main and interaction effects of walking in a VE, walking in a VE with visual perturbations, and walking with light touch proprioceptive feedback. Results: The light touch support caused narrower strides in all VE conditions. This decrease in the base of support could indicate increased confidence in motor planning due to light touch contact. Significance: This letter illustrates that proprioceptive signals from a person-following robot may increase overground stability when the user experiences discordant visual feedback.