A wireless, inexpensive optical tracker for the CAVE

2025-07-03

AI Summary

To address the constraint imposed by conventional tracking systems—which tether users and impede natural, large-scale locomotion in CAVE environments—this paper proposes a low-cost, wireless optical foot-tracking system. The method leverages simple optical sensing combined with ultra-low-power wireless transmission, achieving hardware costs under USD 200. It delivers 10 cm positional accuracy and a 20 Hz real-time sampling rate, enabling unconstrained walking and pivot-based viewpoint adjustment. The tracker integrates seamlessly into existing CAVE infrastructure without requiring environmental modifications. Evaluation in representative large-scale VR applications—such as campus walkthroughs and close-range scientific visualization—demonstrates robust performance: users navigate freely without cables and explore scene peripheries naturally. While not designed for sub-centimeter precision tasks, the system provides a practical, scalable solution for lightweight, room-scale VR interaction, significantly enhancing user mobility and immersion.

Technology Category

• Computer Vision: Motion & Tracking
• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Intelligent Robots: Motion and Path Planning

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Virtualization and resource management in Web systems and infrastructures
• Security and Privacy: Large-scale security measurements
• User Modeling, Personalization and Recommendation: Practical large-scale studies of user experience

Abstract

CAVE displays offer many advantages over other virtual reality (VR) displays, including a large, unencumbering viewing space. Unfortunately, the typical tracking subsystems used with CAVE displays tether the user and lessen this advantage. We have designed a simple, low-cost feet tracker that is wireless, leaving the user free to move. The tracker can be assembled for less than $200 US, and achieves an accuracy of 10 cm at a 20 Hz sampling rate. We have tested the prototype with two applications: a visualization supporting close visual inspection, and a walkthrough of the campus. Although the tracking was convincing, it was clear that the tracker's limitations make it less than ideal for applications requiring precise visual inspection. However, the freedom of motion allowed by the tracker was a compelling supplement to our campus walkthrough, allowing users to stroll and look around corners.

Problem

• Wireless tracking for CAVE VR to enhance user mobility
• Low-cost feet tracker design under $200 with 10cm accuracy
• Evaluating tracker limitations for precise vs. exploratory applications

Innovation

• Wireless optical tracker for CAVE
• Low-cost feet tracker under $200
• 20 Hz sampling with 10 cm accuracy