Establishing Common Conceptual Frameworks: A Reference Model for Augmented Reality

As technological advances in software and devices continue to drive adoption of Augmented Reality, the need has grown for proven, global standards for designing AR-specific products and processes. New and unfamiliar technologies always bring risks of higher project costs being introduced as a result of miscommunication, unfulfilled user expectations and safety, as well as having to invent or “reinvent” processes and taxonomies that have been used elsewhere.

A global standard that is open and promotes clear communication and a common conceptual framework mitigates such risks, and offers many benefits to accelerate the growth of the AR ecosystem of providers and customers by:

• Improving development of new AR-based products and services
• Allaying the fear of vendor lock-in
• Encouraging innovation
• Sharing best practices
• Safeguarding customers and users of products and services

There is a track record of successful adoption of reference models leading to industry growth. The Distributed Computing Reference Model (DCRM) provides enormous benefit to vendors and society served by information technology, having contributed to the growth of the knowledge economy as we know it today. In the domain of Augmented Reality, the AR Community a grassroots organization of AR professionals dedicated to the development of open and interoperable standards, has been contributing to the development of a new conceptual framework: the Mixed and Augmented Reality (MAR) Reference Model. The MAR RM is being prepared for publication using the process defined by the International Standards Organization (ISO). This collaborative effort has produced a working draft of the world’s first comprehensive reference model for Augmented Reality.

Mixed Reality

As the title of the reference model document indicates, Augmented Reality must be understood within the larger context of Mixed Reality, which is the area between our physical world and a 100% computer-generated virtual reality.

http://commons.wikimedia.org/wiki/File:Reality-Virtuality_Continuum.svg Title: Reality-Virtuality Continuum / Giovanni Vincenti

Mixed Reality is more a continuum or spectrum than a box with sharply defined borders, so it makes sense to define standards for the entire area, rather than for Augmented Reality alone. Regarding AR, you can think of it as watching the real world through your device camera, with graphics and other information overlaying your field of view. Farther along, Augmented Virtuality is more like watching a computer-generated environment like a video game, with some of the elements on your screen being real world images captured by the camera.

The concepts, systems and roles of actors within this technological continuum are the focus of the MAR Reference Model.

MAR System and Classes

Besides providing global definitions and terminology, the reference model describes a high-level representation of typical components in a MAR system that recognizes a real world context, registers target physical objects, displays MAR content and handles user interactions. Using the same high level architecture, the reference model defines three viewpoints of the MAR system:

• The Enterprise view describes the purpose and scope of the system, as well as the objectives of different actors and users of MAR components
• The Computational view describes system components, their functions and interfaces
• The Information view describes high-level data flows among components

Each viewpoint, presents a different version of the AR system architecture along with a detailed description of components, data flows, interfaces and actors. Requirements, as well as quality and technical criteria are also defined.

The reference model also presents a helpful classification framework for mapping MAR components to real world applications. Possible applications and services employing features such as camera or haptic user interfaces are organized as system classes, with each class being described as the one below.

MAR Criteria and Use Cases

The document additionally describes criteria for the following qualitative features:

• Performance
• Safety
• Security
• Privacy

The reference model illustrates real world applications by presenting nine Augmented Reality applications with use cases. In the last section of the document, a number of technologies and relevant standards are described.

Conclusion

Based on years of practical application development and industry consensus, the MAR Reference Model will become a valuable guide for AR designers and technology providers to define their own systems and business models. It is currently in ISO draft form with official publication foreseen in the first half of 2015.