MetaSpace II (MS2) is a social Virtual Reality (VR) system where multiple users can not only see and hear but also interact with each other, grasp and manipulate objects, walk around in space, and get tactile feedback. MS2 allows walking in physical space by tracking each user’s skeleton in realtime and allows users to feel by employing passive haptics i.e., when users touch or manipulate an object in the virtual world, they simultaneously also touch or manipulate a corresponding object in the physical world. To enable these elements in VR, MS2 creates a correspondence in spatial layout and object placement by building the virtual world on top of a 3D scan of the real world. Through the association between the real and virtual world, users are able to walk freely while wearing a head-mounted device, avoid obstacles like walls and furniture, and interact with people and objects. Most current virtual reality (VR) environments are designed for a single user experience where interactions with virtual objects are mediated by hand-held input devices or hand gestures. Additionally, users are only shown a representation of their hands in VR floating in front of the camera as seen from a first person perspective. We believe, representing each user as a fullbody avatar that is controlled by natural movements of the person in the real world (see Figure 1d), can greatly enhance believability and a user’s sense immersion in VR.
Two large problems faced by virtual environment designers are lack of haptic feedback and constraints imposed by limited tracker space. Passive haptic feedback has been used effectively to provide a sense of touch to users (Insko, et al, 2001). Redirected walking is a promising solution to the problem of limited tracker space (Razzaque, et al, 2001). However, these solutions to these two problems are typically mutually exclusive because their requirements conflict with one another. We introduce a method by which they can be combined to address both problems simultaneously. Over the past few years, virtual reality has experienced a resurgence. Fueled by a proliferation of consumer-level head-mounted display and motion tracking devices, an unprecedented quantity of immersive experiences and content are available for both desktop and mobile platforms. However, natural locomotion in immersive virtual environments remains a significant challenge. Many of the VR applications available to date require seated use or limit body movement within a small area, instead relying a gamepad or mouse keyboard for movement within the virtual world. Lacking support for natural walking, these virtual reality experiences do not fully replicate the physical and perceptual cues from the real world, and often fall short in maintaining the illusion that the user has been transported to another place. We present a virtual reality demonstration that supports infinite walking within a confined physical space. This is achieved using redirected walking, a class of techniques that introduce subtle discrepancies between physical and virtual motions [ 2001]. When employed properly, redirected walking can be stunningly effective. Previous research has made users believe that they walked in a straight line when they actually traveled in a wide circle, or that they walked between waypoints in a long virtual hallway when in fact they went back and forth between the same two points in the real world. While perceptually compelling, redirected walking is challenging to employ effectively in an unconstrained scenario because users' movements may often be unpredictable. Therefore, our recent research has focused on dynamic planning and optimization of redirected walking techniques, enabling the system to intelligently apply redirection as users explore virtual environments of arbitrary size and shape [ 2014b] [ 2014a]. In this Emerging Technologies exhibit, attendees will explore a large-scale, outdoor immersive virtual environment in a head-mounted display (see Figure 1). The demonstration will support natural walking within a physical area of at least 6x6m, using a wide-area motion tracking system provided by PhaseSpace Inc. The virtual reality scenario will instruct users to scout the environment while stopping to take panoramic photos at various locations in the virtual world. As users explore the environment, our automated planning algorithm will dynamically apply redirection to optimally steer them away from the physical boundaries of the exhibit, thus enabling the experience of limitless walking in a potentially infinite virtual world (see Figure 2). 