If a mobile computing device knows how it is positioned and oriented in relation to other devices nearby, then it can provide enhanced support for multi-device and multi-user interactions. Existing systems that provide position information to mobile computers are reliant on externally deployed infrastructure, such as beacons or sensors in the environment. We introduce the Relate system, which provides fine-grained relative position information to co-located devices on the basis of peer-topeer sensing, thus overcoming dependence on any external infrastructure. The system is realised as a hardware /software plug-in, using ultrasound for peer-to-peer sensing, USB to interface with standard mobile devices, and data abstraction and inferencing to map sensor data to a spatial model that maintains both quantitative and qualitative relationships. We present a set of services and applications to demonstrate the utility of the system. We report experimental results on the accuracy of the relative position and orientation estimates, and other aspects of system performance.

Tabletops have been used to support a range of colocated activities, from games to image sorting. However, their limited display space and resolution can restrict the kinds of collaborative interactions that take place. Our research is concerned with how to extend the tabletop by integrating it with other spaces and artifacts in the physical world. The aim is to continue to support collaborative tasks that are well suited to the tabletop while enabling those that are less so to be carried out using physical representations and spaces. We describe a physical-digital space that we built for this purpose and then a study that compared how groups collaborate on a design task when using this versus solely the tabletop. The findings showed that extending the tabletop into a physical space enabled groups to collaborate more easily and flexibly. 1.

Drawing on ongoing ethnographic investigations into home life, this paper presents detailed findings from a preliminary examination of refrigerator surfaces. The use and organization of items on fridge surfaces are shown to be closely tied to the material properties of both fridges and their surroundings. Emphasis is placed on the importance of fridge magnets as they are seen to contribute to a fluidity and reconfigurability that make fridge surfaces unique. Building on this, it is argued that the negotiation of family relations is afforded by the presented properties of the fridge and of magnets. To conclude, we introduce some general points to consider in designing interactive surfaces for the home. Author Keywords Home life, ethnography, interactive surfaces, refrigerators, magnets.

If a mobile computer knows how it is positioned and oriented in relation to other mobile devices nearby, then it can provide enhanced support for multi-device and multi-user interactions. Existing systems that provide position information to mobile computers are reliant on externally deployed infrastructure, such as beacons or sensors in the environment. We introduce a novel system, Relate, which provides fine-grained relative position information to co-located devices on the basis of peer-to-peer sensing, thus overcoming dependence on any external infrastructure. The system is realized as hardware/software plug-in, using ultrasonic devices for peer-to-peer sensing, USB to interface with standard mobile devices, and data abstraction and inference to map sensor data to a spatial model that maintains both quantitative and qualitative relationships. We present a set of services and applications to demonstrate the utility of the system and report experimental results on system performance.

This paper introduces a new paradigm for describing Tangible User Interfaces (TUI). The paradigm presented here encompasses existing TUI classifications and proposes a unified conceptual framework with which all TUIs can be understood. In order to show that the new paradigm holds and can be generalized we analyzed several existing TUIs using the proposed paradigm.

In this paper, we present a new approach to clinical workplace computerization that departs from the window–based user interface paradigm. NOSTOS is an experimental computer–augmented work environment designed to support data capture and teamwork in an emergency room. NOSTOS combines multiple technologies, such as digital pens, walk–up displays, headsets, a smart desk, and sensors to enhance an existing paper–based practice with computer power. The physical interfaces allow clinicians to retain mobile paper–based collaborative routines and still benefit from computer technology. The requirements for the system were elicited from situated workplace studies. We discuss the advantages and disadvantages of augmenting a paper–based clinical work environment.

Interactions have taken off from the confinement of a single screen into various personal devices. Projected an interface onto different parts of a physical environment is an escape beyond traditional display devices. Imagine that any walls or floors can turn into a direct manipulation space without a lot of effort. This demonstration of ED-lite, a combination of a laptop, custom software, off-the-shelf digital camera and projector, shows projected interfaces with interactions on any surfaces including those not necessarily perpendicular to the projector. ED-lite is a derivation of our previous work on Everywhere Displays (ED) and steerable interfaces. This portable version has an automatic calibration feature that makes applications usable on any surfaces in a drop. More importantly, it is now possible to be taken on the road for demonstrations. ACM Classification Keywords H5.1. Information interfaces and presentation (e.g., HCI);

Models of human work are well recognized means for representing multiple elements of an organization in a mutually tuned form. However, humans and systems tend to use different forms of representation when expressing their knowledge. Most of the widespread modelling approaches focus on a system designer's or software view rather than on intuitive and comprehensive (re)presentations of mental models of users.

Web designers use pens, paper, walls, and tables for explaining, developing, and communicating ideas during the early phases of design. These practices inspired The Designers’ Outpost. With Outpost, users collaboratively author web site information architectures on an electronic whiteboard using physical media (Post-it notes and images), structuring and annotating that information with electronic pens. This interaction is enabled by a touch-sensitive electronic whiteboard augmented with a computer vision system. The Designers’ Outpost integrates wall-scale, paper-based design practices with novel electronic tools to better support collaboration for early-phase design. Our studies with professional designers showed this integration to be especially helpful for fluidly transitioning to other design tools; access and exploration of design history; and remote collaboration.

Tangible interaction shows promise to significantly enhance computer-mediated support for activities such as learning, problem solving, and design. However, tangible user interfaces are currently considered challenging to design and build. Designers and developers of these interfaces encounter several conceptual, methodological and technical difficulties. Among others, these challenges include: the lack of appropriate interaction abstractions, the shortcomings of current user interface software tools to address continuous and parallel interactions, as well as the excessive effort required to integrate novel input and output technologies. To address these challenges, we propose a specification paradigm for designing and implementing Tangible User Interfaces (TUIs), that enables TUI developers to specify the structure and behavior of a tangible user interface using high-level constructs, which abstract away implementation details. An important benefit of this approach, which is based on User Interface Description Language (UIDL) research, is that these specifications could be automatically or semi-automatically converted into concrete TUI implementations. In addition, such specifications could serve as a common ground for investigating both design and implementation concerns by TUI developers from different disciplines. Thus, the primary contribution of this paper is a high-level UIDL that provides developers,