A Fitts' law study of click and dwell interaction by gaze, head and mouse with a head-mounted display

Abstract

Gaze and head tracking, or pointing, in head-mounted displays enables new input modalities for point-select tasks. We conducted a Fitts' law experiment with 41 subjects comparing head pointing and gaze pointing using a 300 ms dwell (n = 22) or click (n = 19) activation, with mouse input providing a baseline for both conditions. Gaze and head pointing were equally fast but slower than the mouse; dwell activation was faster than click activation. Throughput was highest for the mouse (3.24 bits/s), followed by head pointing (2.47 bits/s) and gaze pointing (2.13 bits/s). Dwell activation was faster than click activation. The effective target width for gaze (≈ 94 pixels; about 3 •) was larger than for head and mouse (≈ 72 pixels; about 2.5 •). Subjective feedback rated the physical workload less for gaze pointing than head pointing.

Pointing by gaze, head, and foot in a head-mounted display

“…Our findings confirm the findings from Qian et al [37] and Hansen et al [13] where they reported that head input outperforms gaze. Blattgerste et al [2], however, reported that gaze was much faster than head input.…”

“…This suggests that 3D vs. 2D is of importance for gaze but not for head interaction. The difference between the gaze throughput reported herein and the throughput found previously [13] is most likely due to the equipment used, since they had identical 2D set-ups. Future study is needed, for example, comparing 2D vs. 3D interfaces, motion vs. static background and targets in head space vs. targets in world space.…”

“…The system we tested was particularly slow in the lower hemisphere (see Figure 4), while Hansen et al [13] reported the FOVE HMD to have the same movement time in all directions. The gaze tracking system in the present experiment may solve this issue with improvements in software or hardware.…”

“…They suggest their results might be different from Qian et al 's [37] because they used a more precise gaze tracking system. We note that our work and work by Qian et al [37] and Hansen et al [13] compared gaze and head inputs in a Fitts' law evaluation that conforms to ISO 9241-9. However, Blattgerste et al [2] used point-and-click tasks on a keyboard and a menu, also the field-of-view was varied in the experiment.…”

“…Hansen et al [13] compared pointing with head to pointing with gaze and mouse inputs in a Fitts' law experiment with the same FOVE HMD, but within a neutral 2D (i.e., "flat") scene. The authors compared dwell (300 ms) and mouse click as selection methods.…”