Abstract
Modification of motion of the mouse cursor during the manipulation by the observer evokes visually induced illusory haptic sensation; backward force sensation arises from deceleration of the cursor and forward from acceleration. Studies have been made on the pseudo haptics using conventional 2D motion. This study investigates the illusion using motion-in-depth and second-order motion. A stereoscopic display and a 3D input/force-feedback device SPIDAR were used in the first experiment. The display was on a frontal plane. Subject was asked to manipulate SPIDAR with his/her right hand and to move a visual target in horizontal, vertical, or front-back direction at a constant speed. Changing image size, disparity, and cast shadow were presented to make front-back motion perception. During the manipulation, the speed of the target was reduced to 50% for 0.4sec. Illusory force sensation was measured using the magnitude estimation method. The result indicates that perceived force from motion-in-depth was about 30% of that from horizontal or vertical motion. We speculated anisotropy of vision or hand motion caused this result. A similar experiment, therefore, was conducted with a different display setup. The display was laid flat on the back and subject was asked to look it down. The illusion from 3D motion was about 30% of that from 2D motion. These results indicate that 3D visual motion weakens the illusion. A random-dot display on a 2D monitor and the SPIDAR were used in the second experiment. The motion cue was second order - in each frame, dots in a square patch reversed in contrast (black dots became white and white dots became black). Subject was asked to move the patch in horizontal direction. The result indicates that perceived haptic sensation from second-order motion was about 90% of that from first-order motion.
Meeting abstract presented at VSS 2012