Calibration-free gaze interfaces based on linear smooth pursuit

Abstract

Since smooth pursuit eye movements can be used without calibration in spontaneous gaze interaction, the intuitiveness of the gaze interface design has been a topic of great interest in the human-computer interaction field. However, since most related research focuses on curved smooth-pursuit trajectories, the design issues of linear trajectories are poorly understood. Hence, this study evaluated the user performance of gaze interfaces based on linear smooth pursuit eye movements. We conducted an experiment to investigate how the number of objects (6, 8, 10, 12, or 15) and object moving speed (7.73 ˚/s vs. 12.89 ˚/s) affect the user performance in a gaze-based interface.
 Results show that the number and speed of the displayed objects influence users’ performance with the interface. The number of objects significantly affected the correct and false detection rates when selecting objects in the display. Participants’ performance was highest on interfaces containing 6 and 8 objects and decreased for interfaces with 10, 12, and 15 objects. Detection rates and orientation error were significantly influenced by the moving speed of displayed objects.
 Faster moving speed (12.89 ˚/s) resulted in higher detection rates and smaller orientation error compared to slower moving speeds (7.73 ˚/s).
 Our findings can help to enable a calibration-free accessible interaction with gaze interfaces.

Eye Tracking in Virtual Reality: a Broad Review of Applications and Challenges

“…Due to differences in eye attributes and the geometry of the eye tracking setup, most eye tracking use-cases require users to calibrate the eye tracking system before they can use it. However, some use-cases, such as smooth pursuit-based interaction, just employ the user’s relative eye motion in reaction to scene objects; therefore, they do not need to calibrate the eye tracking system Zeng et al (2020) .…”

Voice as a Mouse Click: Usability and Effectiveness of Simplified Hands-Free Gaze-Voice Selection

“…Moreover, to reduce the number of recalibrations in the experiment, we used a chin rest, which is not a practical solution in most cases. However, while calibration is a necessary part of conventional eye tracking technologies, approaches exist to enable calibration-free eye tracking [29][30][31][32][33], and we expect that this problem could be soon solved in commercial applications. In general, the combined gaze-voice technology necessarily inherits certain issues of the eye tracking-based technology, such as issues in eye pupil tracing in some users, but they could be partly or fully solved with the progress in eye tracking technology.…”

GaVe: A webcam-based gaze vending interface using one-point calibration

“…Pursuit-based interaction is established by matching the trajectories of eye-movement to moving object trajectories on a display (Vidal, Bulling, & Gellersen, 2013). Different types of trajectories can be used, e.g., circular trajectories (Esteves, Velloso, Bulling, & Gellersen, 2015;Niu et al, 2021), linear trajectories (Porta, Dondi, Pianetta, & Cantoni, 2021;Zeng, Neuer, Roetting, & Siebert, 2022;Zeng & Roetting, 2018;Zeng, Siebert, Venjakob, & Roetting, 2020), and irregular trajectories such as an object's outline (Sidenmark, Clarke, Zhang, Phu, & Gellersen, 2020). In comparison to the other gaze interaction methods mentioned above, pursuit-based gaze interaction does not require precise gaze coordinates or personal calibration for a robust gaze-based interaction.…”