Modeling Reach For Use in User Interface Design

The area on a horizontal working plane usable for direct manipulation or direct touch user interfaces is constrained within the space reachable by the users. This paper shows that existing models of reach in the literature are suitable for use in user interface design. While existing data was gathered for stationary individuals this paper examines the impact of freedom of motion on the maximum reported comfortable reach envelope (i.e. the surface of maximum reach). A user study was conducted to gauge the impact at several table heights of user motion on available working space. Throughout, the paper discuses several ways in which these reach models can be immediately applied to user interface design.