How to Realize Ubiquitous VR? ∗ Sehwan Kim, Youngho Lee, and Woontack Woo GIST U-VR Lab. Gwangju 500-712. S. Korea {skim, ylee, wwoo}@gist.ac.kr Abstract. In this paper, we propose a novel concept of Ubiquitous Virtual Reality (U-VR) and promising approaches for realization of U-VR. Currently, Virtual Reality (VR) is not popular in our daily lives despite the development of many devices, and people have few chances to use VR systems since there is no indispensable application area. On the other hand, extensive researches on Ubiquitous Computing (ubiComp) have been carried out to allow applications to adopt to users and environments based on various kinds of contexts obtained from distributed yet invisible computing resources. Thus, we consider how to revive VR in ubiComp environments. We present a concept of U-VR that is realized through Collaborative Wearable MAR (Mediated Attentive Reality). Moreover, we investigate several challenges that are significant factors in establishing U-VR environments. Finally, for raised issues the proposed approaches are illustrated. We prove the usefulness of the presented concept by illustrating some applications. 1 Introduction Until now, VR has strived to build a computer-generated Virtual Environment (VE) to enable a user to feel realism through interaction that stimulates five senses of a human. Especially, recent advances in computer graphics, multimedia, parallel/distributed computing and high-speed networking technologies enable to construct Collaborative Virtual Environments (CVEs) [1]. The participants in the CVEs can collaborate with each other by using audio, video and 3D graphics even though they are located around the world. The CVEs may be distinguished by the following five features: a shared sense of space, a shared sense of presence, a shared sense of time, a way to communicate, and a way to share [2]. Nevertheless, VR is still far from users in a RE, and has no killer applications in our daily lives. On the other hand, the ubiComp paradigm is popular in our daily lives by allowing to access computing resources and services anywhere and at any time [3]. Furthermore, context-aware services can be supplied to users based on the information obtained from distributed but invisible computing resources [4]. It is also worthwhile to note that ubiComp enables to shift a paradigm from technology- ∗ This work was supported partly by ETRI OCR, and partly by the UCN Project, the MIC 21st Century Frontier R&D Program in Korea, under CTRC at GIST. 493