Haptic Direction Indicator for Visually Impaired People Based on Pseudo-Attraction Force

Wayfinding is of vital importance if visually impaired pedestrians are to walk by themselves from one place to another, since they must calculate both their orientation and position. Here, a new haptic direction indicator is proposed, which will help blind pedestrians to avoid hazardous areas intuitively and safely by means of haptic navigation. A novel translational force perception method, called the "pseudo-attraction force" technique, is applied to a haptic direction indicator, which exploits the nonlinear relationship between perceived acceleration and physical acceleration to generate a force sensation. An experiment was performed to clarify the perceptual characteristics when a visually impaired person held the haptic direction indicator. The results indicate that the angular resolution of directional force under 8-direction (compass) conditions was better than that under 12-direction (clock position) conditions with the haptic direction indicator. The finding constitutes a criterion for designing smaller haptic direction indicators.