ARO: Exploring the Design of Smart-Ring Interactions for Encumbered Hands

Abstract

Fingertip computing has seen increased interest through miniaturized smart-rings for augmenting digital peripherals. One key advantage of such always-available input devices is the non-necessity to hold a device for interaction, as it remains affixed to a finger for access when needed. Such a wearable device makes it possible to interaction with content even when the hand is encumbered, by grasping or holding objects. Our investigation aims at understanding the properties of this fundamental smart-ring advantage. We designed a smart-ring prototype, ARO (in-Air, on-Ring, on-Object interaction), which facilitates input while grasping objects. To better identify interaction possibilities, we present the results of an elicitation study through which we grouped various forms of micro-gestures possible with ARO while holding objects under different grasp requirements. We then explored the ability for users to perform different navigation tasks (i.e. zooming and panning) using the smart-ring with encumbered hands. In our studies, users were most efficient when using either In-air or On-ring interactions, in comparisons to gestures detected On-object. Furthermore, In-air was the most preferred by our participants. Based on our findings, we conclude with recommendations for the design of future smart-rings and fingertip devices at large, to allow efficient interaction while hands are encumbered.

In Summary

Smartrings being finger-worn benefit in not having to be carried during interaction (such as with a smartpone) and the potential for one-hand interaction (unlike touch interaction on a smartwatch). The finger-worn location also provides potential for encumbered interaction throughout daily life. Having built a smartring in-house, we explored understudied smartring interaction modalities while encumbered through a range of grasp types.

Key Findings

• We share implementation details for our custom built smartring. The smartring allows for In-Air, On-Ring, and On-Object gesture recognition through a touch capacitive surface and intertial measurement unit.
  • Please note, this smartring has since been iterated upon, and can be seen in a related follow-up work here
• While holding anchored objects, the most preferred interaction location was On-Ring (56.39%) and In-Air (27.37%)
• While holding unanchored objects, the results showed that In-Air was the most preferred (48.06%) interaction location with On-Ring (39.76%) the second most preferred
• Across two usage studies, the In-Air interaction modality was often most preferred and out-performed the other two techniques

In More Detail

Please review our full paper (linked above) for study details, methodologies, and complete results.