In Seamful Design: Showing the Seams in Wearable Computing

this paper, we question the assumption that seamless integration of computer system components is necessarily a design requirement for wearable computing and for ubiquitous computing. We explore Mark Weiser's notions of seamlessness and 'seamfulness', and use them in discussing the design and use of wearable and ubicomp systems. The physical nature of the systems we design reveals itself in, for example, uncertainty in sensing, limited coverage of communications infrastructure, and the transformations needed to share data between heterogeneous tools and media. When such seams show through, as they inevitably do, users perceive and appropriate them for their own uses. However, we suggest that new opportunities for system design arise if we take fuller account of this process. We offer examples of seams and some suggestions for seamful design, drawing from the Equator interdisciplinary research collaboration's work on ubiquitous computing and mixed reality systems. More particularly, we focus on our work in Equator's City project, on a system that lets a visitor using a PDA in a museum exhibition or cultural institution co-visit with people using virtual reality and web versions of the same institution. Our work is strongly influenced by the vision of ubiquitous computing presented by Mark Weiser (1). One of the broader design goals of ubicomp is invisibility: A good tool is an invisible tool. By invisible, I mean that the tool does not intrude on your consciousness; you focus on the task, not the tool. In other words, one no longer needs to attend to the tool when using it. Ubiquity involves multiple, heterogeneous devices providing highly dispersed input, output and computational capabilities. These parts collectively form a tool for interaction that is " literally visible, effectively invisible " because their design, along with one's experience and understanding of them, lets one focus on interaction through the whole instead of on the parts—just as a carpenter does carpentry without a constant and conscious focus on his hammer. However, it appears that this notion of invisibility has been translated into requirements for seamless integration of computer system components, as well as the interactions supported by those components. Seamlessness is an attractive prospect, extending the ideas of metaphoric direct manipulation to make our interactions with computers more literal, reducing the distractions that such interactions currently introduce. However, Weiser describes seamlessness as a misleading or misguided concept. In his invited talks at UIST94 (2) and USENIX95 (3), he suggests that …