Using speech and touch to enable blind people to access schematic diagrams

A novel approach for enabling blind people to interact with computer-generated graphical information is presented. The paper discusses how computer-generated, text-based information is presented to blind people and then identifies the difficulties in providing similar access to the range of graphical information presented by computer systems. A computer-based system that allows blind users to read, create and edit one type of schematic diagram, namely data flow diagrams used in software engineering, is presented, together with the mapping from the original diagram to a suitable generic, tactile diagram. Results of the evaluation of the approach are given, as are suggested adaptations of the approach that can present tabular information and time-ordered schematic diagrams to a user.