Although various attempts have been made at providing the blind with substitute visual perception, no existing method provides useful colour perception of the environment. This paper describes a substitute vision system which provides perception of the three-dimensional profile and colour of the surrounding environment via haptic sensations alone. This is aimed at allowing visually-impaired people to avoid obstacles and navigate the environment by recognising landmarks by their colour and profile. The prototype system uses stereo video cameras to capture colour images of the environment from which a disparity depth map can be calculated. The depth map is sampled into ten range readings, which are communicated to the user via electro-neural pulses in their fingers. The intensity of the pulses is directly proportional to the distance sampled in the corresponding depth map region. Also, the pulse frequency is determined by the predominate colour in that region. Thus by imagining the fingers are extended in the forward direction, the user can feel the distance to objects and their colour based on the approximate direction pointed by each finger. This paper focuses on describing the method employed in achieving 3D colour perception via haptic stimulation and how this form of perception can be used to navigate familiar environments.
Available at: http://works.bepress.com/kward/8/