Extending Fitts' Law for Tapping on Surfaces Angled in the Depth Direction
Naoto Yamakawa, Tatsuya Maruta, Yuichiro Kinoshita, Kentaro Go · 2024
Recently, various shape-changing devices have been reported in the human-computer interaction field. However, the applicability of Fitts’ law to these devices has not been efficiently discussed. Thus, in this study, we discuss the realization of a model that can predict the tapping time of displays angled in the depth direction. We first measured the tapping time of angled touch screens for 18 participants. Based on the results, we expanded and validated the Fitts’ law model by considering the operator’s line of sight. The results of regression analysis between the tapping time and the expanded model indicated that R2 = 0.97 and R2 = 0.95 for the displays angled to the front and back, respectively. We also considered the obstruction due to display height in the convex configuration and tapping difficulty in the concave configuration. The regression analysis for the modified model demonstrated R2 = 0.93 for both front-angled and back-angled displays.