Electronic Locomotion Aids for the Blind: Towards More Assistive Systems

This chapter first presents a review of existing locomotion assistance devices for the blind. These devices are merely proximeters, that measure the distance to the closest obstacles, and convey this information to their users. We introduce the measurement methods (infrared sensors, ultrasonic sensors, laser telemeters) and the user interfaces (sounds and tactile vibrations). Then, we analyse the shortcomings of these systems, and thus explain what additional features new devices could offer. To study the feasibility of such systems, we tackle the different issues raised in the process: localizing users, modeling their environment and adding semantic annotations. Finally, we explain how such devices could fit into a view of ambient intelligence, and how the problems raised extend beyond the field of assistance to blind people.