Roman Rädle

HuddleLamp: Spatially-Aware Mobile Displays for Ad-hoc Around-the-Table Collaboration

We present HuddleLamp, a desk lamp with an integrated RGB-D camera that precisely tracks the movements and positions of mobile displays and hands on a table. This enables a new breed of spatially-aware multi-user and multi-device applications for around-the-table collaboration without an interactive tabletop. At any time, users can add or remove displays and reconfigure them in space in an ad-hoc manner without the need of installing any software or attaching markers. Additionally, hands are tracked to detect interactions above and between displays, enabling fluent cross-device interactions. We contribute a novel hybrid sensing approach that uses RGB and depth data to increase tracking quality and a technical evaluation of its capabilities and limitations. For enabling installation-free ad-hoc collaboration, we also introduce a web-based architecture and JavaScript API for future HuddleLamp applications. Finally, we demonstrate the resulting design space using five examples of cross-device interaction techniques.

Squidy: a zoomable design environment for natural user interfaces

We introduce the interaction library Squidy, which eases the design of natural user interfaces by unifying relevant frameworks and toolkits in a common library. Squidy provides a central design environment based on high-level visual data flow programming combined with zoomable user interface concepts. The user interface offers a simple visual language and a collection of ready-to-use devices, filters and interaction techniques. The concept of semantic zooming enables nevertheless access to more advanced functionality on demand. Thus, users are able to adjust the complexity of the user interface to their current need and knowledge.

Interactive Design of Multimodal User Interfaces

In contrast to the pioneers of multimodal interaction, e.g. Richard Bolt in the late seventies, today’s researchers can benefit from various existing hardware devices and software toolkits. Although these development tools are available, using them is still a great challenge, particularly in terms of their usability and their appropriateness to the actual design and research process. We present a three-part approach to supporting interaction designers and researchers in designing, developing, and evaluating novel interaction modalities including multimodal interfaces. First, we present a software architecture that enables the unification of a great variety of very heterogeneous device drivers and special-purpose toolkits in a common interaction library named “Squidy”. Second, we introduce a visual design environment that minimizes the threshold for its usage (ease-of-use) but scales well with increasing complexity (ceiling) by combining the concepts of semantic zooming with visual dataflow programming. Third, we not only support the interactive design and rapid prototyping of multimodal interfaces but also provide advanced development and debugging techniques to improve technical and conceptual solutions. In addition, we offer a test platform for controlled comparative evaluation studies as well as standard logging and analysis techniques for informing the subsequent design iteration. Squidy therefore supports the entire development lifecycle of multimodal interaction design, in both industry and research.

Spatially-aware or Spatially-agnostic?: Elicitation and Evaluation of User-Defined Cross-Device Interactions

Cross-device interaction between multiple mobile devices is a popular field of research in HCI. However, the appropriate design of this interaction is still an open question, with competing approaches such as spatially-aware vs. spatially-agnostic techniques. In this paper, we present the results of a two-phase user study that explores this design space: In phase 1, we elicited gestures for typical mobile cross-device tasks from 4 focus groups (N=17). The results show that 71% of the elicited gestures were spatially-aware and that participants strongly associated cross-device tasks with interacting and thinking in space. In phase 2, we implemented one spatially-agnostic and two spatially-aware techniques from phase 1 and compared them in a controlled experiment (N=12). The results indicate that spatially-aware techniques are preferred by users and can decrease mental demand, effort, and frustration, but only when they are designed with great care. We conclude with a summary of findings to inform the design of future cross-device interactions.

Blended shelf: reality-based presentation and exploration of library collections

We present the user interface Blended Shelf, which provides a shelf browsing experience beyond the physical location of the library. Blended Shelf offers a 3D visualization of library collections with the integration of real-world attributes like the size and availability of books. The application reflects the actual arrangement of items in the physical library and enables implicit serendipitous support of the shelf browsing process in the digital world. The interface offers multiple views with different levels of detail regarding the collection as well as various entrance points to it. The user can explore and search the shelves by touch interaction. Tracking the users position and line of sight ensures the ideal perspective on the interface. Thus, a user can explore collections in a familiar way and benefit from serendipitous browsing discoveries without forfeiting the advantages of the digital domain.

Virtual Objects as Spatial Cues in Collaborative Mixed Reality Environments: How They Shape Communication Behavior and User Task Load

In collaborative activities, collaborators can use physical objects in their shared environment as spatial cues to guide each others attention. Collaborative mixed reality environments (MREs) include both, physical and digital objects. To study how virtual objects influence collaboration and whether they are used as spatial cues, we conducted a controlled lab experiment with 16 dyads. Results of our study show that collaborators favored the digital objects as spatial cues over the physical environment and the physical objects: Collaborators used significantly less deictic gestures in favor of more disambiguous verbal references and a decreased subjective workload when virtual objects were present. This suggests adding additional virtual objects as spatial cues to MREs to improve user experience during collaborative mixed reality tasks.

Codestrates: Literate Computing with Webstrates

We introduce Codestrates, a literate computing approach to developing interactive software. Codestrates blurs the distinction between the use and development of applications. It builds on the literate computing approach, commonly found in interactive notebooks such as Jupyter notebook. Literate computing weaves together prose and live computation in the same document. However, literate computing in interactive notebooks are limited to computation and it is challenging to extend their user interface, reprogram their functionality, or develop stand-alone applications. Codestrates builds literate computing capabilities on top of Webstrates and demonstrates how it can be used for (i) collaborative interactive notebooks, (ii) extending its functionality from within itself, and (iii) developing reprogrammable applications.

TwisterSearch : a distributed user interface for collaborative Web search

Although a Web search is typically regarded as a solitary activity, collaborative search approaches are becoming an increasingly relevant topic for HCI and distributed user interfaces (DUIs). Today’s collaborative search systems lack comprehensive search support that also involves pre- or post-search activities such as preparing for a search or making sense of search results. We believe that post-WIMP DUIs can help to better support social searches and have identified four design goals that are critical for their successful design. In consequence, we present TwisterSearch, an interactive DUI prototype that meets our four design goals. A formative study conducted with students at a high school shows its general applicability for educational purposes.

eBook meets tabletop: using collaborative visualization for search and serendipity in on-line book repositories

The ever-growing amount of digitized books and electronically published documents necessitates proper tools to search and explore such large digital information spaces. This paper presents the design of an interactive prototype for collaborative visual information seeking (VIS) in an on-line book repository. The main objectives of the prototype are a visual metaphor to query an on-line book repository and the facilitation of back-and-forth comparison of search results. Furthermore, an integrated cosine similarity search encourages for serendipitous discoveries while browsing through an information space.

Die Blended Library : Benutzerorientierte Verschmelzung von virtuellen und realen Bibliotheksdiensten

In diesem Beitrag wird die Idee der „Blended Library“ vorgestellt, welche die Entwicklung von neuen Konzepten fur die Unterstutzung des Rechercheprozesses in der physischen Bibliothek der Zukunft beschreibt. Im Zuge der voranschreitenden Digitalisierung wurden in der Vergangenheit in den unterschiedlichsten Bereichen versucht, reale Dienste der Bibliothek auf digitale Dienste zu ubertragen. Jedoch gingen dadurch viele soziale und physische Mehrwerte realer Umgebungen (z. B. personlicher Kundenkontakt, raumliche Orientierung, greifbare Medienobjekte) verloren. Dieser Beitrag schlagt deshalb einen Paradigmenwechsel vor – weg von der Entwicklung rein virtueller Welten, hin zur Einbettung von Informationstechnologien in die soziale und physische Welt einer Bibliothek. In der Blended Library werden Benutzern somit vollig neue Formen der Recherche und der Wissensvermittlung geboten. Dies soll durch den umfassenden Einsatz von neuen interaktiven Endgeraten und zukunftsweisenden Visualisierungen geschehen und somit reale und virtuelle Angebote bzw. Funktionen der Bibliothek zusammenfuhren. Eine Fallstudie dient dabei als erste exemplarische Umsetzung einer Blended Library, welche umfassend auf den kreativen Arbeitsablauf eines Wissensarbeiters in der Bibliothek der Zukunft eingeht. Das Konzept wird anhand eines realitatsnahen Szenarios vorgestellt, in dem die Designentscheidungen der Fallstudie basierend auf „Conceptual Blending“ erklart werden.