Validating Eyes-free Affordance of On-Finger Hand Proximate User Interfaces in In-situ Scenarios

We explore the value of Hand Proximate User Interfaces (HPUIs) for in-situ interactive head-mounted systems, i.e. systems designed to support a user’s primary activity. HPUIs are unencumbered, single-handed, and have tactile and proprioceptive affordances. This allows novice and expert users to rely on the visual cues available in the UI, but to then gradually interact eyes-free such that they minimize interrupting the user’s core task. Prior work on HPUI falls short of validating this premise. We address this gap with comparative analysis in the context of a compound task, where one hand is involved in a primary task and the second interacts with a secondary but supporting task (e.g. selecting items from a menu). We compare HPUI with mid-air direct interactions, a common form of interacting with head-mounted displays. The results show that HPUI performs similarly to mid-air but with better eyes-free affordances and user preferences.