Assisting the Visually Impaired: Obstacle Detection and Warning System by Acoustic Feedback

Sensors

Alberto Rodríguez¹  J. Javier Yebes¹  Pablo F. Alcantarilla²  Luis M. Bergasa¹  Javier Almazán¹ 

[1] Department of Electronics, University of Alcalá, Alcalá de Henares, 28871 Madrid, Spain; E-Mails:;ISIT UMR 6284 CNRS, Université d’Auvergne, 63001 Clermont-Ferrand, France; E-Mail:

关键词: visually impaired;    obstacle detection;    stereo camera;    ground plane estimation;    audio warning;   

DOI  :  10.3390/s121217476

来源: mdpi

【 摘 要 】

The aim of this article is focused on the design of an obstacle detection system for assisting visually impaired people. A dense disparity map is computed from the images of a stereo camera carried by the user. By using the dense disparity map, potential obstacles can be detected in 3D in indoor and outdoor scenarios. A ground plane estimation algorithm based on RANSAC plus filtering techniques allows the robust detection of the ground in every frame. A polar grid representation is proposed to account for the potential obstacles in the scene. The design is completed with acoustic feedback to assist visually impaired users while approaching obstacles. Beep sounds with different frequencies and repetitions inform the user about the presence of obstacles. Audio bone conducting technology is employed to play these sounds without interrupting the visually impaired user from hearing other important sounds from its local environment. A user study participated by four visually impaired volunteers supports the proposed system.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland