No Door Handle, No Entry! Expressing Cues through a Shape-Changing Door

Computation is increasingly seen as a design material, finding its way into once mundane objects, surfaces and spaces. As such, demonstrations of the convergence of architectural elements and interactive systems are becoming commonplace in both research and industry. While eXtended Reality (XR) and projection mapping technologies seem to be ubiquitous in this field, shape-changing interfaces are under-represented. In this case study we explore the domain of shape-changing thresholds in the form of an interactive door panel. Corresponding to conditions of space occupancy, the design communicates through dynamic affordances and affordance elimination three ascribed social cues: entry invitation, entry permission, and entry prohibition. In a user evaluation study, all participants were able to correctly interpret the entry invitation and the entry prohibition cues. Based on our learnings and findings, we discuss aspects of our design and implications of shape-changing doors.