A survey on wearable devices used to assist the visual impaired user navigation in outdoor environments

In this paper we introduce a comprehensive survey of wearable systems designed to assist the visual impaired users navigation in everyday life outdoor scenarios. We focus on presenting the main advantages and limitations of each technique in effort to inform the scientific community about the progress in the area of assistive devices and also offer users a review about the capabilities of each system. Various performance parameters are introduced in order to classify different systems by giving qualitative and quantitative measures for evaluation. At the end of the study conclusions are presented along with some perspectives for future work and development.