Multi-user, touch-sensing input devices create opportunities for the use of cooperative gestures – multi-user gestural interactions for single display groupware. Cooperative gestures are interactions where the system interprets the gestures of more than one user as contributing to a single, combined command. Cooperative gestures can be used to enhance users ’ sense of teamwork, increase awareness of important system events, facilitate reachability and access control on large, shared displays, or add a unique touch to an entertainment-oriented activity. This paper discusses motivating scenarios for the use of cooperative gesturing and describes some initial experiences with CollabDraw, a system for collaborative art and photo manipulation. We identify design issues relevant to cooperative gesturing interfaces, and present a preliminary design framework. We conclude by identifying directions for future research on cooperative gesturing interaction techniques. Author Keywords Cooperative gestures, gestures, computer-supported

Although electronic media has changed how people interact with documents, today’s electronic documents and the environments in which they are used are still impoverished relative to traditional paper documents when used by groups of people and across multiple computing devices. Vertical interfaces (e.g., walls and monitors) afford a less democratic style of interaction than generally observed when people are working around a table. In this paper, we introduce MultiSpace, a research effort which explores the role of the table as a central hub to support ad hoc collaboration in a multi-device environment. The table-centric approach offers new interaction techniques to provide egalitarian access and shared transport of data, supporting mobility and micromobility [11] of electronic content between tables and other devices. Our observations show how people use these techniques, and how tabletop technology can support and augment collaborative tasks. 1.

PhoneTouch is a novel technique for integration of mobile phones and interactive surfaces. The technique enables use of phones to select targets on the surface by direct touch, facilitating for instance pick&drop-style transfer of objects between phone and surface. The technique is based on separate detection of phone touch events by the surface, which determines location of the touch, and by the phone, which contributes device identity. The device-level observations are merged based on correlation in time. We describe a proofof-concept implementation of the technique, using vision for touch detection on the surface (including discrimination of finger versus phone touch) and acceleration features for detection by the phone.

Gestures can offer an intuitive way to interact with a computer. In this paper, we investigate the question whether gesturing with a mobile phone can help to perform complex tasks involving two devices. We present results from a user study, where we asked participants to spontaneously produce gestures with their phone to trigger a set of different activities. We investigated three conditions (device configurations): phone-to-phone, phone-to-tabletop, and phone to public display. We report on the kinds of gestures we observed as well as on feedback from the participants, and provide an initial assessment of which sensors might facilitate gesture recognition in a phone. The results suggest that phone gestures have the potential to be easily understood by end users and that certain device configurations and activities may be well suited for gesture control.

Recent years have seen a proliferation of secure device pairing methods that try to improve both the usability and security of today’s de-facto standard – PIN-based authentication. Evaluating such improvements is difficult. Most comparative laboratory studies have so far mainly focused on completeness, trying to find the single best method among the dozens of proposed approaches – one that is both rated the most usable by test subjects, and which provides the most robust security guarantees. This search for the “best” pairing method, however, fails to take into account the variety of situations in which such pairing protocols may be used in real life. The comparative study reported here, therefore, explicitly situates pairing tasks in a number of more realistic situations. Our results indicate that people do not always use the easiest or most popular method – they instead prefer different methods in different situations, based on the sensitivity of data involved, their time constraints, and the social conventions appropriate for a particular place and setting. Our study also provides qualitative data on factors influencing the perceived security of a particular method, the users’ mental models surrounding security of a method, and their security needs.

this paper we describe a system to show some limited effects on a static toy-car model and present techniques that can be used in similar setups. Our focus is on creating apparent motion for animation

Abstract Many business models for smart products, like pay-per-use, require that the smart product can digitally verify whether the user has a contract with the smart product and should be granted access to privileged functionality. Traditional means to do so, e.g. password login, are very obtrusive and can thus not be applied for smart product scenarios. In this paper, we present the mechanism of association. Associations represent the abstract concept of a digitally checkable contract on the middleware level. Associations use a service for digitally representing the user that performs the tedious parts of creating a digitally checkable contract automatically. Thus, the interaction can be established unobtrusively. As this service acts on behalf of the user, the user must trust this service. We address this issue in two ways: the service is executed on the personal trusted device of the user and the user can control and inspect the actions of the service via a user interface. Keywords smart products · ubiquitous computing · natural interaction 1

As computing devices become ubiquitous, devices are expected to encounter and associate with one another spontaneously to form ad hoc networks for sharing resources. One of the challenges in research remains in the task of making a device association scheme secure and, at the same time, easy to use. There have been numerous proposed solutions from literatures, with each solution designed for specific purposes and scenarios. At present, there is no clarity of differences and similarities amongst those association methods. In this paper, we present a classification of device association methods based on categories that influence the usability of an association.

Many business models for smart products, like pay-per-use, require that the smart product can digitally verify whether the user has a contract with the smart product and should be granted access to privileged functionality. Traditional means to do so, e.g. password login, are very obtrusive and can thus not be applied for smart product scenarios. In this paper, we present the mechanism of association. Associations represent the abstract concept of a digitally checkable contract on the middleware level. Associations use a service for digitally representing the user that performs the tedious parts of creating a digitally checkable contract automatically. Thus, the interaction can be established unobtrusively. As this service acts on behalf of the user, the user must trust this service. We address this issue in two ways: the service is executed on the personal trusted device of the user and the user can control and inspect the actions of the service via a user interface.

Tablet-size PCs are a burgeoning new computer platform that is becoming increasingly popular for many different tasks. The device falls somewhere between a traditional desktop system and a PDA in terms of both usability and design. Even though the platform has been heavily publicized as the ”next generation mobile business personal computer ” (Dray, Feldman, Siegel, Potenza. 2002), the Tablet PC seems to be suffering from a sort of identity crisis. This could partially be explained by the tendency to treat the platform as either a desktop system, or as a handheld system. It is interesting to explore the platform in and of itself as an avenue for new genres of activities. Two interesting new types of interaction that we propose to investigate, take advantage of the form-factor of the Tablet PC as well as the freedom of pen input. The first example is using the Tablet PC as a metaphor for a coach’s clipboard in some sort of sporting event. The second is as a strategic military planner on the battlefield. 1 SCENARIO 1: COACH’S CLIPBOARD METAPHOR Sporting games are becoming increasingly realistic, with advances in 3D graphics and features like real player statistics, real announcers, and game modes such as franchise mode where you can build