Mechanism and evaluation of a haptic interface “Force Blinker 2” for navigation of the visually impaired

In the navigation of the visually impaired, an external input such as force or sound is required about the direction of travel to reach a particular target position. We develop a new haptic interface called “Force Blinker 2” to navigate the visually impaired. In Force Blinker 2, rotating weights and repulsive magnets are used to reduce the force generated to the direction opposite the traveling direction, which caused false recognition in the previous system, “Force Blinker 1.” In Force Blinker 2, the rotational radius of the weight varies depending on the velocity of the rotational weight. Ten visually impaired subjects evaluated Force Blinker 2 by comparing it with Force Blinker 1, a fixed radius type interface. The directions presented by Force Blinker 2 were correctly recognized at a rate of approximately 85%, which is approximately a 10% improvement over the rate by Force Blinker 1.