Alternative Visualization of Textual Information for People with Sensory Impairment

By virtue of lacking visual feedback or access to verbal communication, people with a sensory impairment use alternative means for information imaging that rely on residual senses. For this reason, a wide range of assistive hardware and software came into the market to provide an efficient way of alternative imaging, for instance, of textual information. Nevertheless, nearly one third of these techniques were withdrawn from the market due to lack of use. Recent innovations offer limited functionality and more often than not, the low accuracy of the produced output hampers the use of assistive aids. Designers should focus not on the technique itself, but on the optimal combination of the intact modalities to provide the disabled user with efficient access to textual information. One of the aims in the adequate use of assistive aids is to shape appropriate modality-specific notions to mediate communication with people having normal abilities. Implementation of the novel assistive techniques may be based on diverse technologies employing speech and speech-like signals, visual and vibro-tactile patterns, which can be used to display unambiguously the semantics of the textual message in a case when the environment has different constraints or the user has inferior perceptive thresholds due to chronic disease. In such cases, the required techniques should provide real-time or close to real time processing and imaging of the textual information so that both ordinary users and people with a sensory impairment would be able to use it autonomously without assistants or interpreters. The foremost purpose of this dissertation is to consider the latest assistive technologies in order to suggest further improvements. Therefore, the summary provides background for the research papers included and an analytical survey of assistive methods/techniques. The problematic aspects affecting the use of computer help for people having ocular pathology and hearing disorders is the particular subject of our study. The considerations presented are intended for the developers of advanced assistive user interfaces. The empirical part of the dissertation consists of a collection of the assistive aids which were designed to augment and expand access to the textual information for people with a sensory impairment. The central idea of this dissertation was blending signals of several modalities to reproduce distinct cases of the recognizable spatial-temporal semantic constructions such as vibrotactile, audio-tactile and color patterns within minimal array of the coding units used for alternative imaging of textual information. Two prototypes of the wearable assistive devices such as BlinkGlasses and TactilePointer and some