This paper reports on user interface design and evaluation for a mobile, outdoor, augmented reality (AR) application. This novel system, called the Battlefield Augmented Reality System (BARS), supports information presentation and entry for situation awareness in an urban war fighting setting. To our knowledge, this is the first time extensive use of usability engineering has been systematically applied to development of a real-world AR system.

Our BARS team has applied a cost-effective progression of usability engineering activities from the very beginning of BARS development. We discuss how we first applied cycles of structured expert evaluations to BARS user interface development, employing user interface mockups representing occluded (non-visible) objects. Then we discuss how results of these evaluations informed our subsequent user-based statistical evaluations and formative evaluations, and present these evaluations and their outcomes. Finally, we discuss how and why this sequence of types of evaluation is cost-effective.