Lan-Xi Dong OCAD University Toronto, Ontario ld13jh@student.ocadu.ca A Tangible User Interface for Interactive Data Visualization ABSTRACT We present a prototype for a Tangible User Interface (TUI) designed to interactively query a database. While much work has been done on TUI, showing that they encourage collaboration and positively enhance user experience, few tangible systems have been designed specifically for data analysis tasks. Our system combines a tabletop (non-digital) graspable user interface with a two-dimensional screen display; the user interrogates the data by placing tokens on or off the tabletop and the screen displays the results of the user’s query. The objects are tagged using fiducial markers, which are identified with open-source ReacTIVision computer vision software, and the visualization code is written in Processing. We use radio station listenership demographic data for this prototype, but the system can be used to query any type of database. Author Keywords Tangible User Interface, Graspable User Interface, 3d Interactions, Interface Design, Database query, Data Analytics, Human Computer Interaction, Collaboration, Collaborative Learning, Collaborative Work Environment, Physical Visualization, Data Materialization ACM Classification Keywords H5.2 User Interfaces: Interaction Styles General Terms Human Factors; Design; Tangible Computing; Collaborative computing INTRODUCTION This work is an extension of work presented at CHI2014 in which we tested user interfaces that used physical blocks to represent data [30]. The user tests were conducted with low-fidelity prototypes using a ‘Wizard of Oz’ approach [8] (in which the system is not automated but operated by an unseen person), and we found that participants expressed a very keen interest in using the tangible interfaces, and seemed to find the user experience very enjoyable; we also found that the tangible interfaces encouraged interpersonal interactions [30]. Here we extend the work by creating a high fidelity prototype, which we present in this paper. A high fidelity prototype will allow us to make more quantitative measurements in our next round of user testing and to explore the full range of natural interaction with the interface. ______________________________________________ ‡Corresponding author Copyright © 2015 Ana Jofre, Steve Szigeti, Stephen Tiefenbach Keller, Lan-Xi Dong, Frederico Tomé, David Czarnowski, Sara Diamond. Permission to copy is hereby granted provided the original copyright notice is reproduced in copies made. Tangible user interfaces (TUI) afford interactions that push the boundaries of traditional WIMP (windows, icons, menus, pointer) interfaces, including the direct manipulation of 2D graphical forms [7], the use of gesture [19] and 3D space [19][17][18]. While many prototypes for TUIs exist, the current state of technology is such that there is no standard input or output device or protocol. As such, each TUI system uses different methods of connecting the physical to the digital. Despite the lack of technological convergence, some common understanding has been reached in how users interact with such systems [28] through the application of theories of cognition [1] and through user testing with various prototypes [13]. Research in TUI explores possible improvements to how we can interact with digital information, particularly with regard to learning [25][23][32][26][20][29][5] and collaborative work [16][9][19][26][13]. Kim and Maher, for example, compared Graphical User Interfaces (GUI) with TUI in a collaborative design task, finding that the groups using TUI performed multiple cognitive actions in a shorter time, made more unexpected discoveries of spatial design features, and exhibited more problem-finding behaviours [16]. MOTIVATIONS AND RELATED WORK We are particularly interested in the role of collaboration, which may be a key differentiator between tangible and WIMP style interfaces [11][19]. Hornecker and Burr explicitly provide a conceptual framework for understanding the social aspects of TUI in their case studies [11]. Lee et al build on this framework, arguing that analysis should include not only the user, but the potential social dimensions of the interaction which takes place when users engage with each other while navigating physical devices [19]. While most current tangible interfaces are designed and studied as tools to enhance playful learning [4][29], to support communication in collaborative work, [9][24], and to augment tele-presence in remote collaborations [2][6], there appears to be significantly less work done on designing a tangible interface specifically for analytic work, such as the one we present in this paper. Shaer et al [27] made an effort to conceptually define a paradigm for standardizing input/output with what they called ‘TAC’ – a Token and Constraint system [14]. Tokens are physical objects that are handled to access or manipulate the digital data, and constraints limit the way in which the user interacts with the token. Constraints set the framework of how the user manipulates the tokens, and ideally, they should be designed to express the set of operations that can be performed on the digital data. One of the first tangible data query systems was designed to interactively convey historical information at a tourist site using Ana Jofre‡ OCAD University Toronto, Ontario ajofre@faculty.ocadu.ca Steve Szigeti OCAD University Toronto, Ontario sszigeti@ocadu.ca Stephen Tiefenbach Keller OCAD University Toronto, Ontario sk14ff@student.ocadu.ca Frederico Tomé OCAD University Toronto, Ontario freddericofilho@gmail.com David Czarnowski OCAD University Toronto, Ontario daveczarnowski@gmail.com Sara Diamond OCAD University Toronto, Ontario sdiamond@ocadu.ca