Interactive balance rehabilitation tool with wearable skin stretch device

Physical interactions between human and machine are essential in facilitating effective physical therapy training programs. Nowadays, physical training largely involves robotic assistive devices or wearable haptics. In this study, we propose a lightweight wearable sensory augmentation device using skin stretch feedback to provide individuals with additional sensory cues during balance training. The goals of this study are i) to determine the effectiveness of the proposed novel system in improving the dynamic stability of healthy individuals and ii) to test the efficacy of additional cutaneous cues in substituting for missing visual feedback in said healthy subjects. The entire system comprises of a haptic wristband, a visual display, and a force platform. The haptic wristband provides real-time skin stretch feedback at the dorsal side of the wrist in response to user's postural sway. Center of pressure (COP) was displayed on a screen and users were asked to move the COP to a target position displayed on the screen by controlling their body posture in the sagittal plane. Results showed that subjects could complete the tasks when they received both visual feedback and skin stretch feedback by shifting their weights. When visual feedback was subsequently removed, subjects successfully interpreted the tactile cues at the wrist from the skin stretch device and completed the tasks. Larger sample size, diverse groups, and longitudinal studies are needed to demonstrate the effectiveness of the proposed device as a balance rehabilitation tool.