Representing User Activity and Product Function for Universal Design

This paper presents a product analysis framework to improve universal design research and practice. Seventeen percent of the US population has some form of a disability. Nevertheless, many companies are unfamiliar with approaches to achieving universal design. A key element of the framework is the combination of activity diagrams and functional models. The framework is applied in the analysis of 20 pairs of products that satisfy a common high level need but differ with one product intended for fully able users and the other intended for persons with some disability or reduced functioning. Discoveries based on the analysis include the observation that differences in typical and universal products can be categorized functionally, morphologically, or parametrically different than typical products. Additionally, simple products appear to be made more accessible through parametric changes whereas more complex products require functional additions and changes.