K-16 instructors perennially face the challenge of helping students understand complex processes and relationships, especially those that make sense only after they are explored in more than one frame of reference.
The differences between a partial and total solar eclipse on the Earth, for example, are best understood by visualizing observations not just from the surface of the Earth but also from the position of the Moon. The outcomes of historic battles may be better understood by exploring the relative ground positions of each opposing force. The full metaphysical message being conveyed by the frescoes in a cathedral is better understood with respect to the pieces’ locations relative to each other in the building.
Field trips or physical models can help immerse students in some topics’ different perspectives, but often budgets, time, or modeling details limit these tools’ usefulness. Thus, instructors are investigating Virtual Reality (VR) as a means for bringing students into interactive, immersive contact with their subjects.
At Villanova University my research team in the Center of Excellence in Enterprise Technology is part of this effort to understand VR’s strengths and weaknesses for classroom use. A brief overview of VR technology will help put our findings in context.
A Brief Overview for Reference
The process of immersing viewers in another frame of reference has a technological pedigree going back at least to the cycloramas of the late 1800’s and early 1900’s. These 360° paintings of major battles or historic events were installed in circular buildings or rooms with circumferences of 60-100 feet and wall heights of 15-40 feet. An audience seated in the cyclorama would hear a narration of various elements in the painting to help immerse them visually, aurally, and intellectually in the scene.
Developers of devices such as the Sensorama in the 1950’s started a technology lineage from the cyclorama that sought to give individual viewers immersive experiences. Viewers sat in a semi-enclosed booth in front of a stereo viewer with audio speakers on the sides of their enclosures.
Through the 1970’s this lineage produced heavy Head-Mounted Displays (HMDs) that were suspended from the ceiling and worn like a diver’s helmet over the head. As the viewer walked around, a stereo display in the device produced the illusion of moving in a virtual space. Modern HMDs now weigh about a pound or less. They fit snugly on the viewer’s head, with a display over each of the viewer’s eyes to give the effect of viewing depth. In many places VR is being investigated as a classroom tool via HMDs connected to laptops.
During the last half of the 20th century, IMAX and 3D theatre technology developed along another cyclorama lineage that focused on immersive group experiences.
In 1992 another technology called CAVE (CAVE Automatic Virtual Environment) was unveiled at the University of Illinois at Chicago. CAVEs use rear-projected screens to create an enclosure within which a person wearing lightweight 3D glasses sees a virtual world based on stereo projections on the screens. A viewer wears infrared tracking markers that enable the displays to reflect changes in the viewer’s head orientation and body position. Viewers place infrared tracking markers on their hands, allowing them to manipulate virtual objects.
CAVEs can have from one to several screens, depending on the desired degree of enclosure. With a single-panel display viewers always face forward, but if the screen is wide, several viewers can see VR material simultaneously. The figure below shows a typical CAVE layout.