This paper provides an analysis of the long-term, iterative design process of the ColorTable, a complex tangible user interface (TUI) supporting various stakeholders in collaboratively envisioning and discussing urban projects through constructing mixed reality scenes. The TUI has been iteratively designed, evaluated and redesigned in a series of real-world participatory design workshops over a 4-year period. We reflect on the most prominent redesign decisions related to (a) the sensing technology, (b) the physical objects, (c) the places for interaction and (d) the visual representations, in order to identify a series of 10 dimensions describing the design space of the ColorTable. Our aim is to provide new insights to the elaboration of design strategies of TUIs by describing the scope and complexity of the design space of a feature-rich TUI designed in a long-term, iterative process.

Computational Thinking (CT) is an emerging topic in school curricula. Different tools exist to support the learning of CT, namely visual programming languages and tangible development platforms (TDP), which are widely used in extra-curricular activities. To date, few tools have been developed that consider both teachers’ needs and the school context. We designed the Kniwwelino Classroom Kit (KCK) in order to support the teaching of CT in classrooms. This paper presents the results of a pilot study, in which the KCK was used in three primary and three secondary schools in Luxembourg. The KCK is based on Kniwwelino, a creative environment designed for children from 8 years old to learn about programming and electronics. The study explored the suitability of the KCK for teaching CT in primary and secondary schools, focusing on three research questions: (1) how the KCK supports teachers’ pedagogical practices, (2) how the KCK fulfils the pedagogical objectives set by teachers, and (3) the user experience of the KCK (for teachers and pupils). To assess how the KCK meets the three above-mentioned objectives, we used a mixed method approach, combining semi-guided interviews, logbooks, and several questionnaires. We learned that the KCK is versatile enough to adapt to different environments, objectives, and pedagogical approaches, which responds to the first two research questions, and thus offers a great deal of freedom to teachers. The fun and tangible approach of the KCK introduces programming and enables pupils to develop both CT and soft skills such as communication and collaboration. Teachers’ feedback on their user experience was positive, particularly concerning stimulation, novelty, and attractiveness. KCK was evaluated as interesting, valuable, and good, but it was noted that some improvements needed to be made to make it easier, more predictable, and faster. The pupils also rated their user experience positively, with values that were generally on a par with previous studies reported in the state of the art regarding the use of Scratch and BBC Micro:bit in school-based experiments for learning CT. Drawing from these learnings, we list several recommendations for the development of other similar TDP tools to support the teaching of CT in a classroom setting. These recommendations concern the material, programming interface, connection, educational material, and the creation of a community.

To support collaboration, researchers from different fields have proposed the design principles of shareability (engaging users in shared interactions around the same content) and positive interdependence (distributing roles and information to make users dependent on each other). While, on its own, each principle was shown to successfully support collaboration in different contexts, these principles are also partially conflicting, and their combination creates several design challenges. This paper describes how shareability and positive interdependency were jointly implemented in an interactive tabletop-mediated environment called Orbitia, with the aim of inducing collaboration between three adult participants. We present the design details and rationale behind the proposed application. Furthermore, we describe the results of an empirical evaluation focusing on joint problem-solving efficiency, collaboration styles, participation equity, and perceived collaboration effectiveness.

One of the main benefits of large interactive surfaces (e.g. wall-sized displays) lies in their support for collocated collaboration by facilitating simultaneous interactions with the displays and high awareness of other group members' actions. In the context of remote collaboration, this awareness information needs to be acquired through digital means such as video feeds, which typically offer very limited information on non-verbal communication aspects, including on workspace awareness. We describe a new approach we have implemented to tackle that challenge through a multimodal pipeline that deals with tracking, attributing, transmitting, and visualising non-verbal information through what we refer to as workspace awareness cues, across wall-sized displays placed at distant locations. Our approach relies on commodity depth cameras combined with screen configuration information to generate deictic cues such as pointing targets and gaze direction. It also leverages recent artificial intelligence breakthroughs to attribute such cues to identified individuals and augment them with additional gestural interactions. In the present paper, we expand on the details and rationale behind our approach, describe its technical implementation, validate its novelty with regards to the existing literature, and report on early but promising results from an evaluation we conducted based on a mixed-presence decision-making scenario across two distant wall-sized displays.