Tech-note: Multimodal feedback in 3D target acquisition

We investigated dynamic target acquisition within a 3D scene, rendered on a 2D display. Our focus was on the relative effects of specific perceptual cues provided as feedback. Participants were asked to use a specially designed input device to control the position of a volumetric cursor, and acquire targets as they appeared one by one on the screen. To compensate for the limited depth cues afforded by 2D rendering, additional feedback was offered through audio, visual and haptic modalities. Cues were delivered either as discrete multimodal feedback given only when the target was completely contained within the cursor, or continuously in proportion to the distance between the cursor and the target. Discrete feedback prevailed by improving accuracy without compromising selection times. Continuous feedback resulted in lower accuracy compared to discrete. In addition, reaction to the haptic stimulus was faster than for visual feedback. Finally, while the haptic modality helped decrease completion time, it led to a lower success rate.