Calibration During a Pointing Task in a Touchless Interface

In HoverVerse touchless interaction system, people interact with a screen projected on a surface with hand gestures. This study examined whether users can recalibrate their pointing accuracy based on visual feedback in a touchless interface. Affordances refer to the possibilities for action that the environment offers relative to an individual’s capabilities. Because perceiving an affordance depends on movements that are properly scaled to the environment, calibration is the process through which people become attuned to the lawful information for pointing. In our study, the cursor feedback presented on screen specify the perceived action possibilities for pointing accurately to targets. For our study, we recruited seventeen undergraduate students and used a within-subjects design, where participants performed pointing movements, controlling a cursor between pairs of targets projected on a screen. Participants performed the task across three phases (12 trials each): pre-test and post-test (cursor invisible), calibration (cursor visible). On each trial, participants performed six alternating pointing movements between two targets, following a 40 BPM metronome. The targets varied in distance and position relative to the shoulder. Pointing accuracy improved in post-test versus pre-test, indicating that participants learned to be more accurate by refining their pointing behavior using cursor feedback from calibration phase.