Tactile-Enhanced VR Rehabilitation: Integrating Mixed Reality and Scene Transitions

Virtual Reality (VR) technologies are increasingly utilized in motor rehabilitation for their ability to create immersive, controllable environments that support therapeutic activities. However, the combined effects of tactile feedback and mixed reality (MR) transitions on user engagement and usability remain underexplored. To address this gap, we designed and implemented a modular VR rehabilitation system featuring customizable silicone-based tactile texture and seamless MR transitions, enabling dynamic switching between virtual and realworld stimuli. Through collaboration with clinicians at a local rehabilitation hospital, we optimized the system's therapeutic applicability, ensuring alignment with real-world rehabilitation requirements. A series of experiments involving participants systematically evaluated the system's impact across four perceptual dimensions (immersion, motivation, agency, and presence) by comparing four conditions: baseline VR, VR with tactile feedback, VR with MR transitions, and combined tactile+MR. Results indicated that tactile feedback alone achieved the highest perceptual scores, while the combination of tactile feedback and MR transitions also yielded high and stable ratings. The System Usability Scale (SUS) analysis demonstrated good usability ($M=$ 72.3), with usability slightly exceeding learnability. These findings underscore the potential of simple, scalable tactile solutions combined with MR transitions to enhance engagement and usability in VR rehabilitation systems.