Construction and Analysis of a Novel Wearable Assistive Device for a Visually Impaired Person

Algorithm 1.

Algorithm for working of the proposed assistive device.

(1) Manual setting of distance limit in belt module for obstacle normal to the user,

 and distance limit in ankle module for obstacle in front direction of the user.

(2) Setting mode: If setting button is on;

  (a) = current distance calculated by 45°-up sensor.

  (b) = current distance calculated by 45°-down sensor.

(3) Operating mode: if setting button is off;

  (I) If

   Instruction 1: “Obstacle in front”

  (II) If < & >

   Instruction 2: “Small obstacle in front”

  (III) If <

   Instruction 3: “Obstacle at head-level”

  (IV) If >

   Instruction 4: “Pit in ground”

  (V) If < & <

   Instruction 5: “Small obstacle or footpath ahead”

  (VI) If < & >

   Instruction 6: “Table or chair ahead”