Near Field Virtual Reality on a Linux Desktop

Robert van Liere

Near-field virtual reality allows users to interact with virtual objects within arm's reach of the user. Environments for near-field VR are well suited for direct precise interaction by taking advantage of the user's hand-eye coordination.

We discuss the design and experience of a near-field virtual environment, the Personal Space Station (PSS). The PSS consists of a mirror in which stereoscopic images are reflected. The head tracked user reaches under the mirror to interact with the virtual world. The primary motivations for building the system are to provide an ergonomical VR environment that can be used under normal office working conditions, that allows for direct natural interaction, and that is low cost.

The PSS is driven by a desktop PC running Linux. A multithreaded software environment coordinates and manages the multiple input streams. In-house image processing software is used for the reconstruction of 3D points from the calibrated stereo cameras. A fully configured PSS consists of a high end stereo enabled graphics running at 1280x1024 @ 120Hz (for the 3D graphics rendering), two high end frame grabbers with camaras @ 60 Hz in PAL resolution (for interaction tracking), two firewire ibot cameras @ 30 Hz in PAL resolution (for head tracking), and three foot pedals connected to the parallel port (for button clicks). The frame grabber and firewire boards are connected to the PCI bus.

The talk will focuss on the various architectural aspects for the development of the PSS. We discuss various requirements of a PSS and the technical tradeoffs for running such environments on a desktop PC. In particular, tradeoffs of running the PSS on single / SMP / distributed CPUs, the bandwidth needed for rendering / tracking, and techniques for lowering tracking latencies will be addressed.

Dr. ir. Robert van Liere is a senior researcher at Center for Mathematics and Computer Science (CWI) in Amsterdam, where he heads a Visualization and Virtual Reality research group. He also holds a part-time position as associate professor at the Technical University in Eindhoven. Prior to joining CWI in 1985 he worked at TNO-IBBC, a Dutch institute for building and construction research in Rijswijk. Robert received a Ph.D. in computer science from University of Amsterdam and a master degree in computer science from University of Delft. His research interests involve interactive visualization, virtual reality, and human-computer interaction.

Last modified: Mon, 9 Jun 2003 21:08:47 +0200