UML4ALL Syntax – A Textual Notation for UML Diagrams

UML-based software modelling addresses the needs of sighted people but creates barriers for visually impaired people. Textual representations are a general premise to make modelling languages accessible for people with blindness, but their degree of accessibility differs. This paper presents the UML4ALL syntax designed to address the sequential way of working of blind people using screen reader technology. The proposed UML notation comprises four principles introduced in this paper. An evaluation with sighted and visually impaired people showed that the UML4ALL syntax has a good usability for both target groups.