A Stereo Vision-Based Aid for the Visually-Impaired

This paper describes a portable vision-based obstacle detection system, intended for use by blind people. The system combines an obstacle detection system designed for AGVs with recalibration of ground position and a Kalman Filter based model of the person's walking movement. The system uses stereo vision. Obstacle detection is achieved through comparison of the disparity seen with that expected from the position of the ground. Recalibration of ground position is made by plane fitting in the ground region. Motion estimation using two visual methods and the use of an inclinometer is described. The results show satisfactory success in all parts of the system.