What is Augmented Reality (AR)? How could this concept be applied at KSC? These are but a few of the questions that our project struggled with in trying to expand body wearable computer technology to other parts of the space center.

Augmented Reality Defined
Augmented reality is a computer generated, interactive, three dimensional environment in which a person is immersed (Aukstakalnis & Blatner 1992). In short, it is the overlaying of information on to real world objects. The user receives information from both the environment and the computer. The user perceives the world as everyone else, but additional information in the form of text or even videos which augments the real world object. Thus, the user can interact with a mixed virtual and real world in a natural way.
This feat is accomplished through the use of a body wearable computer (BWC){ the technician to the left is wearing one}. A BWC is a battery-powered computer system worn on the user's body (on a belt, backpack or vest). It is designed for mobile and predominantly hands-free operations, often incorporating head-mounted displays and speech input.
Several experimenters have been working with integrating virtual and real objects (Feiner et al 1993, Dykstra 1993) Although AR technology superficially seems to be a technology that will only be first introduced in the year 2000 and beyond, it has already been applied for a number of years. A weather reporter incorporates this technology into every broadcast. The reporter typically stands in front of a blank green or blue screen. Through a technique known as "chroma-keying," the reporter augments this real world object with computer generated information.

By having more information readily at hand, better and faster decisions can be made. This is especially important during troubleshooting problems that involve many people and resources. In addition to better decision making, rapid explanation or demonstration of a task can be performed. Below are listed several examples of data that could be very helpful to a user in aerospace industry applications:

Scenario for Augmented Reality Application
Tension in the clean room mounted as troubleshooting on the anti-matter experiment progressed. The final cover had just been removed and the launch site engineer switched back to the troubleshooting procedure on her body wearable computer. The CAD overlays, graphically showing all the bolt and fastener locations, had speeded the removal process. All 6 of the Principle Investigators (PI)'s had just come online, and through a sea of cameras in the clean room, were "virtually" huddled around the mass of exposed transistors and transducers. As the troubleshooting procedure continued, the problem was isolated to a transducer not being set properly. It was removed and placed in a robotic interface that allowed the PI located at MIT to manipulate the transducer to the correct setting. Within 30 minutes the transducer was back in place and the experiment correctly operating. The first of the 2005 experiments was now back on schedule.

This futuristic scenario may seem unusual today. Tomorrow, challenges in our evolving technological society may demand similar methods. The question is will we be ready to employ these methods.

Visualization for Construction
As mankind further inhabits the vast frontiers of space, a number of structures will need to be constructed whether in orbit, the Moon, or Mars. A structure in the shape of a geodesic dome would be very complicated. The correct placement of the spars would be critical to its successful construction. AR technology could provide a visual representation of where each spar should be placed. Another example in which AR technology could be very helpful would be the construction of radio-telescopes on the far side of the moon. The struts and spars that would be assembled inherently have a complicated nature. The time saved tomorrow is well worth our investment in this new technology today. An excellant site for further information as well as some practical examples of this example see Augmented Reality for Construction.

The Virtual/Real World Interface: Trackers
The success or failure of Augmented Reality applications falls upon the coupling mechanism of both the real and virtual world. Currently there is exist no tracking mechanism that is entirely adequate. For example, magnetic trackers are not accurate enough, mechanical trackers are cumbersome, and vision-based trackers demand high computational wages. A solution may be a hybrid tracking methodology that combines the accuracy of vision-based tracking with the robustness of magnetic tracking without compromising real-time performance or usability. The University of North Carolina is looking into Hybrid tracking systems.

For more information about Augmented Reality, see MIT'sweb site.

March 11, 1998