Activity-Centric Computing Systems

• Activity-Centric Computing (ACC) addresses deep-rooted information management problems in traditional application centric computing by providing a unifying computational model for human goal-oriented ‘activity,’ cutting across system boundaries. • We provide a historical review of the motivation for and development of ACC systems, and highlight the need for broadening up this research topic to also include low-level system research and development. • ACC concepts and technology relate to many facets of computing; they are relevant for researchers working on new computing models and operating systems, as well as for application designers seeking to incorporate these technologies in domain-specific applications

Activity-based computing: computational management of activities reflecting human intention

An important research topic in artificial intelligence is automatic sensing and inferencing of contextual information, which is used to build computer models of the user’s activity. One approach to build such activity-aware systems is the notion of activity-based computing (ABC). ABC is a computing paradigm that has been applied in personal information management applications as well as in ubiquitous, multidevice, and interactive surface computing. ABC has emerged as a response to the traditional application- and file-centered computing paradigm, which is oblivious to a notion of a user’s activity context spanning heterogeneous devices, multiple applications, services, and information sources. In this article, we present ABC as an approach to contextualize information, and present our research into designing activity-centric computing technologies

Bonjour! Greeting Gestures for Collocated Interaction with Wearables

International audienceWearable devices such as smartwatches (SW) and head-worn displays (HWD) are gaining popularity. To improve the collocated capabilities of wearables, we need to facilitate collocated interaction in a socially acceptable manner. In this paper we propose to explore widespread used greeting gestures such as handshakes or head gestures to perform collocated interactions with wearables. These include pairing devices or information exchange. We analyze the properties of greetings and how they can map to different levels of wearable pairing (family, friend, work, stranger). This paper also suggest how these gestures could be detected with SWs and HWDs

WRISTBAND.IO:expanding input and output spaces of a Smartwatch

Smartwatches are characterized by their small size designed for wearability, discretion, and mobile interactions. Most of the interactivity, however, is limited to the size of the display, introducing issues such as screen occlusion and limited information density. We introduce Wristband.io, a smartwatch with an extended interaction space along the wristband, enabling (i) back-of-band interaction using a touchpad, (ii) a low resolution ambient watchband display for offscreen notification, and (iii) tangible buttons for quick, eyes-free input. Insights gained through a study show that back-of-band input increases accuracy and task completion rates for smaller on-screen targets. We probe the design space of Wristband.io with three applications

WRISTBAND.IO:expanding input and output spaces of a Smartwatch

Smartwatches are characterized by their small size designed for wearability, discretion, and mobile interactions. Most of the interactivity, however, is limited to the size of the display, introducing issues such as screen occlusion and limited information density. We introduce Wristband.io, a smartwatch with an extended interaction space along the wristband, enabling (i) back-of-band interaction using a touchpad, (ii) a low resolution ambient watchband display for offscreen notification, and (iii) tangible buttons for quick, eyes-free input. Insights gained through a study show that back-of-band input increases accuracy and task completion rates for smaller on-screen targets. We probe the design space of Wristband.io with three applications

An Activity-Centric Approach to Configuration Work in Distributed Interaction

The widespread introduction of new types of computing devices, such as smartphones, tablet computers, large interactive displays or even wearable devices, has led to setups in which users are interacting with a rich ecology of devices. These new device ecologies have the potential to introduce a whole new set of cross-device and cross-user interactions as well as to support seamless distributed workspaces that facilitate coordination and communication with other users. Because of the distributed nature of this paradigm, there is an intrinsic difficulty and overhead in managing and using these kind of complex device ecologies, which I refer to as configuration work. It is the effort required to set up, manage, communicate, understand and use information, applications and services that are distributed over all devices in use and people involved. Because current devices and their containing software are still document- and application-centric, they fail to capture and support the rich activities and context in which they are being used. This leaves users without a stable concept for cross-device information management, forcing them to perform a large amount of manual configuration work. In this dissertation, I explore an activity-centric approach to configuration work in distributed interaction. The central goal of this dissertation is to develop and apply concepts and ideas from Activity-Centric Computing to distributed interaction. Using the triangulation approach, I explore these concepts on a conceptual, empirical and technological level and present a framework and use cases for designing activitycentric configurations in multi-device information systems. The dissertation presents two major contributions: First, I introduce the term configuration work as an abstract analytical unit that describes and captures the problems and challenges of distributed interaction. Using both empirical data and related work, I argue that configuration work is composed of: curation work, task resumption lag, mobility work, physical handling and articulation work. Using configuration work as a problem description, I operationalize Activity Theory and Activity-Centric Computing to mitigate and reduce configuration work in distributed interaction. By allowing users to interact with computational representations of their real-world activities, creating complex multi-user device ecologies and switching between cross-device information configurations will be more efficient, more effective and provide better support for users’ mental model about a multi-user and multi-device environment. Using activity configuration as a central concept, I introduce a framework that describes how digital representations of human activity can be distributed, fragmented and used across multiple devices and users. Second, I present a technical infrastructure and four applications that apply the concepts of activity configuration. The infrastructure is a general purpose platform for the design, development and deployment of distributed activitycentric systems. The infrastructure simplifies the development of activity-centric systems as it presents complex distributed computing processes and services into high level activity system abstractions. Using this infrastructure and conceptual framework, I describe four fully working applications that explore multi-device interactions in two specific domains: office work and hospital work. The systems are evaluated and tested with end-users in a number of lab and field studies

EagleSense:tracking people and devices in interactive spaces using real-time top-view depth-sensing

Real-time tracking of people's location, orientation and activities is increasingly important for designing novel ubiquitous computing applications. Top-view camera-based tracking avoids occlusion when tracking people while collaborating, but often requires complex tracking systems and advanced computer vision algorithms. To facilitate the prototyping of ubiquitous computing applications for interactive spaces, we developed EagleSense, a real-time human posture and activity recognition system with a single top-view depth sensing camera. We contribute our novel algorithm and processing pipeline, including details for calculating silhouetteextremities features and applying gradient tree boosting classifiers for activity recognition optimised for top-view depth sensing. EagleSense provides easy access to the real-time tracking data and includes tools for facilitating the integration into custom applications. We report the results of a technical evaluation with 12 participants and demonstrate the capabilities of EagleSense with application case studies

CurationSpace:Cross-Device Content Curation Using Instrumental Interaction

For digital content curation of historical artefacts, curators collaboratively collect, analyze and edit documents, images, and other digital resources in order to display and share new representations of that information to an audience. Despite their increasing reliance on digital documents and tools, current technologies provide little support for these specific collaborative content curation activities. We introduce CurationSpace - a novel cross-device system - to provide more expressive tools for curating and composing digital historical artefacts. Based on the concept of Instrumental Interaction, CurationSpace allows users to interact with digital curation artefacts on shared interactive surfaces using personal smartwatches as selectors for instruments or modifiers (applied to either the whole curation space, individual documents, or fragments). We introduce a range of novel interaction techniques that allow individuals or groups of curators to more easily create, navigate and share resources during content curation. We report insights from our user study about people's use of instruments and modifiers for curation activities

Reconfiguration Strategies with Composite Data Physicalizations

Composite data physicalizations allow for the physical reconfguration of data points, creating new opportunities for interaction and engagement. However, there is a lack of understanding of people's strategies and behaviors when directly manipulating physical data objects. In this paper, we systematically characterize diferent reconfguration strategies using six exemplar physicalizations. We asked 20 participants to reorganize these exemplars with two levels of restriction: changing a single data object versus changing multiple data objects. Our fndings show that there were two main reconfguration strategies used: changes in proximity and changes in atomic orientation. We further characterize these using concrete examples of participant actions in relation to the structure of the physicalizations. We contribute an overview of reconfguration strategies, which informs the design of future manually reconfgurable and dynamic composite physicalizations.</p