As a platform, XR or virtual and immersive environments, augmented or mixed reality is becoming more stable and commonplace. The leveraging of existing hardware means it may become ubiquitous. XR has uses that go beyond the conventional view of this technology, that it is only a novelty, or form of entertainment. Healthcare and education are benefiting from the use of XR. It can be used to help students and professionals visualize and interact with complex subjects such as performing medical procedures, training people for potentially dangerous situations and promoting industrial safety.
This evolution is bringing rich interactive media to a new level. Firstly, static informational web pages gave way to interactive content and controls. Media such as audio and video, running first with plug-ins, and then natively in the browser opened up a world of movies, education and gaming. Now XR is set to burst out of the browser, even out of the device, and into our lives.
What does this technology mean for people with disabilities? There are certainly challenges for people with disabilities in successfully using XR. These range from the need for controls that do not need a high degree of precision to use, or require bodily motion, to the need for better color contrast, improved captioning, and object descriptions for blind users.
In making XR accessible on the design and developer side there are also challenges. Building on accessibility best practice and lessons learned in the 2D web, some of the challenges for authors include; how to successfully provide appropriate semantics and support the complex interoperability of assistive technology. Other challenges exist such as ensuring our standards and guidelines successfully address the needs of people with disabilities.
The art of the possible
In many ways XR pushes the envelope of both what is possible and what is needed in a considerable way. For example, we are familiar with browser accessibility application programmable interfaces (APIs) being the necessary bridge between the document object model (DOM) and assistive technology. While these APIs will need to be supported for the assistive technology of today they may well disappear and become redundant. In a future where an XR environment has suitable semantics, descriptions of objects and relatable affordances built into them, these accessibility APIs may just not be needed. The assistive technology itself may just become a part of the platform.
Today, as current browser accessibility APIs are used to meet the needs of assistive technologies, an accessibility architecture is needed within evolving XR. A suitable accessibility architecture should support important accessibility annotations used to describe environmental content or controls. Environmental or object state changes need to be passed to assistive technologies also.
Towards a better understanding of user needs
XR designers and developers therefore need to better understand what accessibility user needs are. W3C/WAI is active in this space. To layout these challenges, the W3C Web Accessibility Initiative (WAI) have published ‘XR Accessibility User Requirements (XAUR)’ as a First Public Working Draft. This work is designed to inform the reader of potential user needs for people with disabilities. Its role is to initiate discussion and gather feedback in order to address gaps.
XAUR is published by the Research Questions Task Force (RQTF). RQTF is a task force of the Accessible Platform Architectures (APA) Working Group at W3C. The APA works to ensure W3C specifications provide support for accessibility to people with disabilities. From these user needs were drafted a set of user requirements that may be implemented at a system or platform level. Some may be authoring requirements. Those listed may then feed into the development of new normative Web Content Accessibility Guidelines (WCAG) success criteria and other technology standards that may advance the development of accessible architectures in XR.
Please note, in the context of this document we are outlining generic draft user requirements only. Those listed are not normative. This means they do not represent a series of things that you must do to conform to any current accessibility standard. This is a first public draft of what may inform the development of other accessibility guidelines.
Exploring an XR Accessibility Architecture
RQTF is also exploring novel approaches to an XR accessibility architecture that can support these user needs. This involves looking at interesting possibilities such as the role of Object Orientated semantics or semantic scene graphs in supporting XR accessibility. RQTF is exploring how to support the accessibility user needs outlined in the document.
This explainer outlines current XR development methods, existing gaps and some current approaches, such as the Accessibility Object Model (AOM) and its potential to provide richer semantics for assistive technologies.
We welcome your feedback!
Your feedback will inform future work in accessibility standards like WCAG, and other technical specifications. We are actively looking for your input on the development of this document. We welcome feedback on our architectural ideas also.
This work is supported by the EC WAI-GUIDE Project.