Tactile Line Drawings for Improved Shape Understanding in Blind and Visually Impaired Users

摘要

Members of the blind and visually impaired community rely heavily ontactile illustrations – raised line graphics on paper that are felt by hand – tounderstand geometric ideas in school textbooks, depict a story in children’sbooks, or conceptualize exhibits in museums. However, these illustrationsoften fail to achieve their goals, in large part due to the lack of understandingin how 3D shapes can be represented in 2D projections. This paper describesa new technique to design tactile illustrations considering the needs of blindindividuals. Successful illustration design of 3D objects presupposes identificationand combination of important information in topology and geometry.We propose a twofold approach to improve shape understanding. First, weintroduce a part-based multi-projection rendering strategy to display geometricinformation of 3D shapes, making use of canonical viewpoints andremoving reliance on traditional perspective projections. Second, curvatureinformation is extracted from cross sections and embedded as textures inour illustrations.