User Interactions for Augmented Reality Smart Glasses: A Comparative Evaluation of Visual Contexts and Interaction Gestures

Smart glasses for wearable augmented reality (AR) are widely used in various applications, such as training and task assistance. However, as the field of view (FOV) in the current AR smart glasses is narrow, it is difficult to visualize all the information on the AR display. Besides, only simple interactions are supported. This paper presents a comparative and substantial evaluation of user interactions for wearable AR concerning visual contexts and gesture interactions using AR smart glasses. Based on the evaluation, it suggests new guidelines for visual augmentation focused on task assistance. Three different types of visual contexts for wearable AR were implemented and evaluated: stereo rendering and direct augmentation, and non-stereo rendering and indirect augmentation with/without video background. Also, gesture interactions, such as multi-touch interaction and hand gesture-based interaction, were implemented and evaluated. We performed quantitative and qualitative analyses, including performance measurement and questionnaire evaluation. The experimental assessment proves that both FOV and visual registration between virtual and physical artifacts are important, and they can complement each other. Hand gesture-based interaction can be more intuitive and useful. Therefore, by analyzing the advantages and disadvantages of the visual context and gesture interaction in wearable AR, this study suggests more effective and user-centric guidance for task assistance.