Collision Warning Device for Blind and Visually Impaired

Participants with blindness or severe visual field loss (hemianopia or tunnel vision) will be
trained to use a collision warning device that alerts them to impending collisions.
Participants will use the device at home during everyday mobility for 2 months. The device is
designed to supplement existing mobility devices, such as a long cane or dog guide. The
device will provide warnings about potential collisions with mid- or high-level obstacles
(which are typically not detected by a long cane).

Inclusion Criteria:

- Blindness (or very limited vision with visual acuity no better than "counting
fingers"),

- Or severe peripheral field loss / tunnel vision (≤ 40° remaining visual field) with
visual acuity of at least 20/200,

- Or homonymous hemianopia with visual acuity of at least 20/200;

- Able to walk independently either with or without mobility aids such as a long cane or
guide dog (but without the aid of a sighted guide);

- Reports at least minor bumps or collisions within the last 3 months;

Exclusion Criteria:

- Currently participating in a mobility training program

- Diagnosed dementia

- Significant cognitive decline

- Participants with hemianopia will be excluded if they have hemianopia for less than 3
months and/or have spatial neglect