Organic User Interfaces

Until recently, the ways in which we interacted with computers were limited by the flat, rigid and rectangular form factors of cathode-ray tubes and liquid crystal displays. Technical limitations forced user interfaces into boxes, limiting interactions to 2D pointing and keyboard input. With technological advances in flexible sensor and display technologies, we are experiencing a new revolution in human– computer interaction (HCI): one in which user interfaces can be worn on the body as if they were cloth, used in the office as if they were paper and used in architecture as if they were wallpapers (Co and Pashenkov, 2008; Buechley and Mellis, 2010; Lahey et al., 2011). Rather than being rigid and static, the user interfaces of tomorrow will be able to have a shape that accommodates the user’s context and fits the data on display. For instance, if a user wants to explore geographic information, they can use a spherical display that does not require distortion of the earth projection (Stevenson, 2010). When reading an interactive map, users can extend their mobile’s screen real estate by unfolding their pocket-size flexible e-paper display. We call such novel user interfaces as organic user interfaces (OUI): interfaces with non-flat multi-touch displays that can exist in both rigid or flexible form factors (Holman and Vertegaal, 2008; Vertegaal and Poupyrev, 2008). OUIs can have any shape that everyday products can have, and can potentially change shape: this flexibility can be driven by either user manipulation or actuators inside the display. OUIs are an interplay of computation and form through a renewed focus on computational materiality. OUIs are opening up unprecedented opportunities for innovation over the next decade of HCI that require us to re-examine and re-evaluate some of the most basic user interface design principles. Following the significant interest resulting from the publication of the special issue of Communication of ACM on OUIs (Vertegaal and Poupyrev, 2008), the first workshop on OUIs and transitive materials at CHI 2009 (Coelho et al., 2009) and the second workshop on OUIs at TEI 2011 (Girouard et al., 2011), this special issue seeks to debate and develop further the concepts behind the OUI vision and stimulate research in related areas, such as in tangible, embedded and embodied interfaces. We invited researchers from a broad spectrum of disciplines to explore emerging materials, prototype nextgeneration interfaces, create tools to design OUIs and discuss the concept and future of this new interface paradigm. With anthropomorphic resonances, Bongers (2013) presents a historical context of OUIs in art, architecture and design. Through a journey of his own work supplemented by broader discussion, Bongers examines the evolution of organic musical interfaces, liquid architecture and video-based projects. Bongers links human centred design—including human-shaped or anthropomorphic design—to the customized design for individuals. He observes that new techniques in design and 3D printing will allow for mass customization of products that meet individual needs. Holman et al. (2013) outline the need for new methods of non-planar interactive design, which includes technologies for rapid hardware prototyping. The authors present SketchSpace, a system for sketching OUIs without hardware components to provide functional interactive behaviours to passive 3D objects. SketchSpace uses depth sensing and projection to provide a board range of sensors and interactions to common objects. Holman et al. concludes by discussing the concept of hypercontextualized design, in which computational objects will have minimal, specialized interactive content pertaining to one particular task. Zhu et al. (2013) offers a tool to support OUIs as well as a taxonomy of papercraft manipulation. They present two novel methods to provide multi-channel wireless power transfer in papercraft devices, through selective inductive power transmission. Their oscillation prototype can provide enough power to activate shape memory alloys and Nichrome wire, while their amplifier prototype can light up LEDs and heat thermochromic ink. This novel technology can wirelessly actuate folds in a paper substrate, to create wireless self-folding origami. Through the exploration of MoleBot, a robotic tabletop creature, Lee et al. (2013) focus their research on the physical transformability of object surfaces. MoleBot suggests the presence of a mole that lives and moves under an interactive table surface, creating a molehill along its path. Located under