Neck Goes VRrr: Reducing Rotation-Induced Virtual Reality Sickness through Neck Muscle Vibrations

With the widespread use of virtual reality (VR), VR sickness is becoming a key barrier for users to have prolonged VR experience. To alleviate VR sickness, researchers focused on reducing sensory mismatch by aligning the visual information with other sensory cues during the VR experience. We present a wearable haptic interface enabling neck muscle vibration (NMV) with a multi-stimulus configuration. NMV's vibration on muscle spindles causes a haptic proprioceptive illusion of muscle stretch. Through NMV, we provide a simulated sensation of neck rotation to users without physically rotating the neck. For a left and right rotation on the yaw axis, we vibrated the sternocleidomastoid (SCM) muscles and splenius capitis (SC) muscles. Our lightweight interface vibrates different combinations of actuators on the left and right SCM and SC muscles to deliver multi-stimulus NMV in a desired illusory direction. We found that NMV sensation differs among individuals and is less effective during neck rotation. Based on these results, we developed a calibration and rendering process for NMV using real-time VR rotation information with varying viewpoint control. Our evaluation, which used a VR scene mimicking a common VR experience, showed that NMV effectively reduces rotation-induced VR sickness and improves the overall VR experience, such as presence.