A Substitute Vision System for Providing 3D Perception and GPS Navigation via Electro-Tactile Stimulation

This paper describes a novel approach for enabling the blind to achieve obstacle avoidance and navigation in outdoor environments with the aid of visual sensors, GPS and electro-tactile stimulation. The electro-neural vision system (ENVS) works by extracting a depth map from stereo cameras by measuring the disparity between the stereo images. This range data is then delivered to the fingers via electro-neural stimulation to indicate to the user the range of objects being viewed by the cameras. To perceive the location of obstacles and the 3D structure of the environment the user imagines that the hands are held in the direction viewed by the cameras, with fingers extended, and the amount of stimulation felt by each finger indicates the range of objects in the direction pointed at by each finger. Also, the relative location of significant landmarks is determined using GPS and stored GPS coordinates and delivered to the fingers via encoded pulses when the landmarks are in the field of view of the stereo cameras. This intuitive means of perceiving the 3D structure of the environment and the location of landmarks in real time effectively enables the user to navigate the environment without use of the eyes or other blind aids. Experimental results are provided demonstrating the potential that this form of 3D environment perception has at enabling the user to achieve localisation, obstacle avoidance and navigation without using the eyes.