No abstract

Usability evaluations are important to improving handheld augmented reality (HAR) systems. However, no standard questionnaire considers perceptual and ergonomic issues found in HAR. The authors performed a systematic literature review to enumerate these issues. Based on these issues, they created a HAR usability scale that consists of comprehensibility and manipulability scales. These scales measure general system usability, ease of understanding the information presented, and ease of handling the device. The questionnaires' validity and reliability were evaluated in four experiments, and the results show that the questionnaires consistently correlate with other subjective and objective measures of usability. The questionnaires also have good reliability based on the Cronbach's alpha. Researchers and professionals can directly use these questionnaires to evaluate their own HAR applications or modify them with the insights presented in this article.

Inspection tasks focus on observation of the environment and are required in many industrial domains. Inspectors usually execute these tasks by using a guide such as a paper manual, and directly observing the environment. The effort required to match the information in a guide with the information in an environment and the constant gaze shifts required between the two can severely lower the work efficiency of inspector in performing his/her tasks. Augmented reality (AR) allows the information in a guide to be overlaid directly on an environment. This can decrease the amount of effort required for information matching, thus increasing work efficiency. AR guides on head-mounted displays (HMDs) have been shown to increase efficiency. Handheld AR (HAR) is not as efficient as HMD-AR in terms of manipulability, but is more practical and features better information input and sharing capabilities. In this study, we compared two handheld guides: an AR interface that shows 3D registered annotations, that is, annotations having a fixed 3D position in the AR environment, and a non-AR picture interface that displays non-registered annotations on static images. We focused on inspection tasks that involve high information density and require the user to move, as well as to perform several viewpoint alignments. The results of our comparative evaluation showed that use of the AR interface resulted in lower task completion times, fewer errors, fewer gaze shifts, and a lower subjective workload. We are the first to present findings of a comparative study of an HAR and a picture interface when used in tasks that require the user to move and execute viewpoint alignments, focusing only on direct observation. Our findings can be useful for AR practitioners and psychology researchers.

Figure 1: We created a usability scale for evaluating handheld augmented reality (HAR) applications. We defined our usability scale based on perceptual and ergonomic issues encountered by users, and then assessed it using three experiments representative of common HAR tasks. AbstractHandheld augmented reality (HAR) applications must be carefully designed and improved based on user feedback to sustain commercial use. However, no standard questionnaire considers perceptual and ergonomic issues found in HAR. We address this issue by creating a HAR Usability Scale (HARUS).To create HARUS, we performed a systematic literature review to enumerate user-reported issues in HAR applications. Based on these issues, we created a questionnaire measuring manipulability -the ease of handling the HAR system, and comprehensibilitythe ease of understanding the information presented by HAR. We then provide evidences of validity and reliability of the HARUS questionnaire by applying it to three experiments. The results show that HARUS consistently correlates with other subjective and objective measures of usability, thereby supporting its concurrent validity. Moreover, HARUS obtained a good Cronbach's alpha in all three experiments, thereby demonstrating internally consistency.HARUS, as well as its decomposition into individual manipulability and comprehensibility scores, are evaluation tools that researchers and professionals can use to analyze their HAR applications. By providing such a tool, they can gain quality feedback from users to improve their HAR applications towards commercial success.

In this poster we present the design and evaluation of a Handheld Augmented Reality (HAR) prototype system for guidance.