Pro-Tact: Hierarchical Synthesis of Proprioception and Tactile Exploration for Eyes-Free Ray Pointing on Out-of-View VR Menus

We introduce Pro-Tact, a novel eyes-free pointing technique for interacting with out-of-view (OoV) VR menus. This technique combines rapid rough pointing using proprioception with fine-grain adjustments through tactile exploration, enabling menu interaction without visual attention. Our user study demonstrated that Pro-Tact allows users to select menu items accurately (95% accuracy for 54 items) in an eyes-free manner, with reduced fatigue and sickness compared to eyes-engaged interaction. Additionally, we observed that participants voluntarily interacted with OoV menus eyes-free when Pro-Tact’s tactile feedback was provided in practical VR application usage contexts. This research contributes by introducing the novel interaction technique, Pro-Tact, and quantitatively evaluating its benefits in terms of performance, user experience, and user preference in OoV menu interactions.