Till Nagel

mæve --- An Interactive Tabletop Installation for Exploring Background Information in Exhibitions

This paper introduces the installation maeve: a novel approach to present background information in exhibitions in a highly interactive, tangible and sociable manner. Visitors can collect paper cards representing the exhibits and put them on an interactive surface to display associated concepts and relations to other works. As a result, users can explore both the unifying themes of the exhibition as well as individual characteristics of exhibits. On basis of metadata schemata developed in the MACE (Metadata for Architectural Contents in Europe) project, the system has been put to use the Architecture Biennale to display the entries to the Everyville student competition.

Traffic Origins: A Simple Visualization Technique to Support Traffic Incident Analysis

Traffic incidents such as road accidents and vehicle breakdowns are a major source of travel uncertainty and delay, but the mechanism by which they cause heavy traffic is not fully understood. Traffic management controllers are tasked with routing repair and clean up crews to clear the incident and often have to do so under time pressure and with imperfect information. To aid their decision making and help them understand how past incidents affected traffic, we propose Traffic Origins, a simple method to visualize the impact road incidents have on congestion. Just before a traffic incident occurs, we mark the incident location with an expanding circle to uncover the underlying traffic flow map and when it ends, the circle recedes. This not only directs attention to upcoming events, but also allows us to observe the impact traffic incidents have on vehicle flow in the immediate vicinity and the cascading effect multiple incidents can have on a road network. We illustrate this technique using road incident and traffic flow data from Singapore.

Touching transport - a case study on visualizing metropolitan public transit on interactive tabletops

Due to recent technical developments, urban systems generate large and complex data sets. While visualizations have been used to make these accessible, often they are tailored to one specific group of users, typically the public or expert users. We present Touching Transport, an application that allows a diverse group of users to visually explore public transit data on a multi-touch tabletop. It provides multiple perspectives of the data and consists of three visualization modes conveying tempo-spatial patterns as map, time-series, and arc view. We exhibited our system publicly, and evaluated it in a lab study with three distinct user groups: citizens with knowledge of the local environment, experts in the domain of public transport, and non-experts with neither local nor domain knowledge. Our observations and evaluation results show we achieved our goals of both attracting visitors to explore the data while enabling gathering insights for both citizens and experts. We discuss the design considerations in developing our system, and describe our lessons learned in designing engaging tabletop visualizations.

Interactive exploration of geospatial network visualization

This paper presents a tabletop visualization of relations between geo-positioned locations. We developed an interactive visualization, which enables users to visually explore a geospatial network of actors. The multitouch tabletop, and the large size of the interactive surface invite users to explore the visualization in semi-public spaces. For a case study on scientific collaborations between institutions, we applied and improved several existing techniques for a walk-up-and-use system aimed at scientists for a social setting at a conference. We describe our iterative design approach, our two implemented prototypes, and the lessons learnt from their creation. We conducted user evaluation studies at the two on-location demonstrations, which provide evidence of the prototype usability and usefulness, and its support for understanding the distribution and connectivity in a geospatial network.

Venice unfolding: a tangible user interface for exploring faceted data in a geographical context

We introduce Venice Unfolding, a case study on tangible geo-visualization on an interactive tabletop to enable the exploration of architectural projects in Venice. Our tangible user interface consists of a large display showing projects on a map, and a polyhedral object to browse these data interactively by selecting and filtering various metadata facets. In this paper we describe a prototype employing new methods to communicate territorial data in visual and tangible ways. The object reduces the barrier between the physical world and virtual data, and eases the understanding of faceted geographical data, enabling urban planners and citizens alike to participate in the discovery and analysis of information referring to the physical world.

Unfolding – a library for interactive maps

Visualizing data with geo-spatial properties has become more important and prevalent due to the wide spread dissemination of devices, sensors, databases, and services with references to the physical world. Yet, with existing tools it is often difficult to create interactive geovisualizations tailored for a particular domain or a specific dataset. We present Unfolding, a library for interactive maps and data visualization. Unfolding provides an API for designers to quickly create and customize geo-visualizations. In this paper, we describe the design criteria, the development process, and the functionalities of Unfolding. We demonstrate its versatility in use through a collection of examples. Results from a user survey suggests programmers find the library easy to learn and to use.

Visualizing Geospatial co-authorship data on a multitouch tabletop

This paper presents Muse, a visualization of institutional coauthorship of publications. The objective is to create an interactive visualization, which enables users to visually analyze collaboration between institutions based on publications. The easy to use multitouch interaction, and the size of the interactive surface invite users to explore the visualization in semi-public spaces.

Shanghai Metro Flow: Multiple Perspectives into a Subway System

One of the main characteristics of cities is the large amount of people moving around. These flows are reflected in all the subways dashing through the city. With the authors’ work, they strive to give an impression of this pulse of the city. They present Shanghai Metro Flow, consisting of an animated visualization composed of three scenes, each giving another perspective into the metro network, and an accompanying poster showing subway line details. Each visualization combines established techniques with a highly aesthetic form in order to attract people to observe and dwell on different aspects of urban mobility.

Sankey Arcs - Visualizing edge weights in path graphs

Arc diagrams allow exploring relations and their strength between sequential nodes. Previous solutions suffer from displaying all arcs at the center of a node, which can lead to visual obstruction. We present a new technique, which extends the arc diagram technique by laying out the weighted edges of a node adjacent to each other. The aim of our Sankey Arc technique is to improve clarity, to enable users perceiving and comparing weighted edges in path graphs. The technique is illustrated using a dataset on travel paths in a public transit network.