This study examines the performance of participants who are blind and have light perception or less when using a secondary electronic travel aid (ETA) and their primary mobility system (e.g., cane, vs. their performance with a cane, alone). The secondary devices studied were the Miniguide US™ and the K Sonar Device™
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. The participants’ performance was measured by their ability to detect obstacles on the vertical and horizontal planes; detect drop-offs and curbs; detect and avoid overhead obstructions, and determine natural and man-made landmarks that could possibly be used for orientation. In addition, the variable “speed of execution” was measured. Increased or decreased efficacy between the participants’ performance with their primary system alone and their performance using both their primary mobility system and one of the two secondary electronic travel aids in conjunction were measured.
