Handsfree Locomotion Techniques for Mobile VR

Abstract

Virtual reality is an area experiencing unprecedented growth due to the release of consumer-ready, affordable, and accessible head mounted displays. Many of these HMDs come in the form of low-cost smartphone adapters, such as Google Cardboard, that can turn any phone into a virtual reality device, paving the way for mass adoption of VR. However, input in mobile VR is typically limited to using head tracking or single button input, which makes it difficult to perform complex tasks like navigation. Walking-in-place (WIP) offers a natural and immersive form of virtual locomotion that can potentially reduce cybersickness. WIP, however, is difficult to implement in mobile contexts as it typically relies on bulky controllers or an external camera. This work presents a novel hands-free WIP technique usable for mobile VR, as well as an alternative hands-free input technique using head tilt. Two user studies are presented. In the first, we show that WIP is more immersive than another popular handsfree navigation method, without any loss in overall performance. In the second, we develop an extension of the WIP technique that uses head tilt and WIP, and compare that to a joystick and a tilt-only technique. These techniques allow users to explore an unlimited amount of virtual space, and are more immersive than traditional input methods, making them ideal for mainstream implementation in virtual reality applications.