A Cave Automatic Virtual Environment (CAVE) system in virtual reality (VR) is an immersive virtual reality display system characterized by placing the user in a three-dimensional space formed by projection screens, allowing the user to interact with the virtual world almost as if they were physically present in the virtual environment. Unlike common head-mounted display (HMD) VR, it does not rely on wearable devices, but instead achieves an immersive experience through spatial projection and sensors.
The following are the core features and principles of the CAVE system:
1. System Structure
Enclosed or semi-enclosed space: Typically a room-sized space where the walls, ceiling, and even the floor are projection screens.
Multi-sided projection: Generally, there are at least three sides (left, right, and front) projected, and some systems even have five or six sides for full coverage.
Stereoscopic display: Used in conjunction with stereoscopic glasses (polarizing or shutter glasses) to achieve three-dimensional stereoscopic vision.
2. Working Principle
Computer-generated virtual scene: High-performance computers render the virtual environment in real time.
Projection onto screens: Projectors project the virtual scene onto the walls, floor, or ceiling.
Tracking user position:
The system is equipped with sensors (such as infrared cameras, magnetic sensors) to track the user's head, hands, or body position.
The projected content is dynamically adjusted according to the user's viewpoint to ensure realistic perspective and field of view.
Interaction:
Users can interact with virtual objects using data gloves, 3D mice, or controllers.
The system updates the virtual scene in real time based on user actions.
3. Advantages
Multi-user sharing: Unlike personal HMDs, CAVE allows multiple people to experience the same virtual environment simultaneously.
Strong immersion: Full-range projection visually "surrounds" the user, reducing dizziness.
Suitable for professional use: Widely used in scientific research, industrial design, architectural visualization, medical simulation, and other fields.
4. Limitations
High cost: Requires multiple high-performance projectors and a large space.
Limited space: Requires a dedicated space for setup.
Limited movement: The user's movement within the space is limited.
Simple understanding: A CAVE is like a room-sized "virtual 3D cinema." When you walk in, it's like entering a virtual world, where the surrounding walls become screens, displaying a three-dimensional scene consistent with the real world, and allowing for interaction.