VRInsole: An Unobtrusive and Immersive Mobility Training System for Stroke Rehabilitation

What other virtual reality interventions does your doctor have you doing? 95 posts on virtual reality.
VRInsole: An Unobtrusive and Immersive Mobility Training System for Stroke Rehabilitation

H. Oagaz, A. Sable, M. Choi, and F. Lin are with the Department of Computer Science and Engineering, University of Colorado Denver, Denver, CO 80204 USA. (e-mail:{hawkar.oagaz, anurag.sable, min.choi, feng.2.lin}@ucdenver.edu).  

Abstract— Stroke is a leading cause of long-term impairment, causing a fatality if not act upon in time. Home-based post-stroke rehabilitation plays an important role in helping patients to regain normal mobility and functionality at their residence. However, existing home-based rehabilitation approaches fail to effectively motivate patients on frequent engagement with exercise to achieve the intended outcome. In this paper, we develop VRInsole, a synthetical solution combining a Smart Insole footwear sensor and virtual reality (VR), targeting lower extremity mobility training in an immersive environment for stroke rehabilitation. Specifically, the motion information collected from the Smart Insole serve as the input for the VR to perform corresponding exercise animations. To prove the feasibility of VRInsole, an experiment is conducted on the recognition of lower extremity motion direction, which achieves an average accuracy of 93.9%. I. INTRODUCTION Stroke is one of the leading causes of long-term ailments, affecting 795,000 people every year in the U.S., out of which 185,000 are recurrent attacks [1]. Deficits following stroke lead to increased rates of fatality or a repeated episode of stoke. Therefore, these individuals require training of movement to optimize their mobile performance with the long-term goal of decreasing fatality rate post stroke and improving balance efficiency.  While many clinical treatments are available for poststroke rehabilitation, it may not be within every patient’s reach. Thus, encouraging patients to practice activities outside of therapy times has been advocated for in rehabilitation. Also, frequently practicing contributes significantly to regain as much motion function as possible. The current rehabilitation practice relies on the static written home program, which is a monotonous repetition and has no encouragement for patients to motivate and refine their motion. The lack of motivation, and assistance in such environments, makes the existing home-based therapy ineffective [2].  In this paper, we proposed VRInsole, a home-based, virtual reality (VR) assisted environment that will promote selfmanagement across the lifespan in stroke rehabilitation, with a focus on the lower extremity mobility training. It is a synthetical solution comprising of an unobtrusive Smart Insole footwear device and a head-mounted VR device. Smart Insole can be used in home environments, record foot motion data over extended time, and provide these data for creating VR animation. Many research works have shown the potential


effectiveness of VR in rehabilitation therapy[3]. Moreover, VR has demonstrated improvement in walking ability and motor function in general[4, 5]. Therefore, the intention of using VR was to motivate stroke patients to practice more often by providing an immersive near-real environment and feedback on exercise quality. This proposed system is intended to overcome the shortfalls of the current standard of care of written home exercise programs [6] to guide rehabilitation efforts after discharge from clinical therapy services. II. RELATED WORK A. VR-based Rehabilitation Several systems for upper extremity rehabilitation using VR are available in our society. Some utilize off-the-shelf hardware such as Nintendo Wii U VR [7]. In academia, Jack et al. [8] used a Cyber-Glove to interact with a VR environment for hand function rehabilitation. Frisoli et al. [9] presented an upper-limb force-feedback exoskeleton for robotic-assisted rehabilitation in VR. The exoskeleton measures the user’s activity and converts it into VR movement. However, no such system is available for lower extremity mobility rehabilitation. B. Exergames Various exergames such as SoccAR [10] use an augmented reality (AR)-based approach for creating fast-paced, motivated games to promote health-related benefits in home and social environments. These systems mainly create a virtual environment to motivate users and provide a suitable scenario wherein the user can perform physical activities. However, these exergames focus more on daily life and sports activities rather than dedicated rehabilitation tasks for stroke patients. III. SYSTEM DESIGN A. System Overview The overall VRInsole workflow diagram is illustrated in Fig. 1. A patient who is demanded to perform exercises for stroke rehabilitation is supplied with a Smart Insole wearable sensor worn with the shoe. After the user performing exercise routines as prescribed by the VR system, the acceleration, and angular velocity data were generated by the inertial motion unit (IMU) sensor embedded in Smart Insole and were sent to a connected VR system. After that, the VR system can utilize the obtained data to recognize the user’s activity and render the activity in a virtual environment. 
W. Xu is with the Department of Computer Science and Engineering, State University of New York at Buffalo, Buffalo, NY 14260 USA (e-mail: wenyaoxu@buffalo.edu).  Corresponding author: Feng Lin, phone: 303-315-0161; e-mail: feng.2.lin@ucdenver.edu.