This article characterizes actuation techniques for generating movement in shape-changing displays with physically reconfigurable geometry. To date, few works in human–computer interaction literature provide detailed and reflective descriptions of the implementation techniques used in shape-changing displays. This hinders the rapid development of novel interactions as researchers must initially spend time understanding technologies before prototyping new interactions and applications. To bridge this knowledge gap, the authors propose a taxonomy that classifies actuator characteristics and simplifies the process for designers to select appropriate technologies that match their requirements for developing shape displays. They scope the investigation to linear actuators that are used in grid configurations. The taxonomy is validated by (a) examining current implementation techniques of motorized, pneumatic, hydraulic, magnetic, and shape-memory actuators in the literature, (b) constructing prototypes to address limited technical details and explore actuator capabilities in depth, (c) describing a use-case scenario through a case study that details the construction of a 10 × 10 actuator shape-display, and (d) a set of guidelines to aid researchers in selecting actuation techniques for shape-changing applications. The significance of their taxonomy is twofold. First, the authors provide an original contribution that enables HCI researchers to appropriately select actuation techniques and build shape-changing applications. This is situated amongst other past works that have investigated broader application scenarios such as a shape-changing vocabulary, a framework for shape transformations, material properties, and technical characteristics of various actuators. Second, they carry out in-depth investigations to validate their taxonomy and expand the knowledge of vertical actuation in shape-changing applications to enable rapid development.

Physical data representations, or data physicalizations, are a promising new medium to represent and communicate data. Previous work mostly studied passive physicalizations which require humans to perform all interactions manually. Dynamic shape-changing displays address this limitation and facilitate data exploration tasks such as sorting, navigating in data sets which exceed the fixed size of a given physical display, or preparing "views" to communicate insights about data. However, it is currently unclear how people approach and interact with such data representations. We ran an exploratory study to investigate how non-experts made use of a dynamic physical bar chart for an open-ended data exploration and presentation task. We asked 16 participants to explore a data set on European values and to prepare a short presentation of their insights using a physical display. We analyze: (1) users' body movements to understand how they approach and react to the physicalization, (2) their hand-gestures to understand how they interact with physical data, (3) system interactions to understand which subsets of the data they explored and which features they used in the process, and (4) strategies used to explore the data and present observations. We discuss the implications of our findings for the use of dynamic data physicalizations and avenues for future work.

Shape-changing displays - visual output surfaces with physically-reconfigurable geometry - provide new challenges for content generation. Content design must incorporate visual elements, physical surface shape, react to user input, and adapt these parameters over time. The addition of the 'shape channel' significantly increases the complexity of content design, but provides a powerful platform for novel physical design, animations, and physicalizations. In this work we use ShapeCanvas, a 4×4 grid of large actuated pixels, combined with simple interactions, to explore novice user behavior and interactions for shape-change content design. We deployed ShapeCanvas in a café for two and a half days and observed users generate 21 physical animations. These were categorized into seven categories and eight directly derived from people's personal interest. This paper describes these experiences, the generated animations and provides initial insights into shape-changing content design.

This paper presents ShapeClip: a modular tool capable of transforming any computer screen into a z-actuating shape-changing display. This enables designers to produce dynamic physical forms by "clipping" actuators onto screens. ShapeClip displays are portable, scalable, fault-tolerant, and support runtime re-arrangement. Users are not required to have knowledge of electronics or programming, and can develop motion designs with presentation software, image editors, or web-technologies. To evaluate ShapeClip we carried out a full-day workshop with expert designers. Participants were asked to generate shape-changing designs and then construct them using ShapeClip. ShapeClip enabled participants to rapidly and successfully transform their ideas into functional systems.

Visualizations such as bar charts help users reason about data, but are mostly screen-based, rarely physical, and almost never physical and dynamic. This paper investigates the role of physically dynamic bar charts and evaluates new interactions for exploring and working with datasets rendered in dynamic physical form. To facilitate our exploration we constructed a 10x10 interactive bar chart and designed interactions that supported fundamental visualisation tasks, specifically; annotation, filtering, organization, and navigation. The interactions were evaluated in a user study with 17 participants. Our findings identify the preferred methods of working with the data for each task i.e. directly tapping rows to hide bars, highlight the strengths and limitations of working with physical data, and discuss the challenges of integrating the proposed interactions together into a larger data exploration system. In general, physical interactions were intuitive, informative, and enjoyable, paving the way for new explorations in physical data visualizations.

In this paper we explore, through a formative study, user preferences for indoor navigation support using a combination of mobile and fixed displays along with a range of navigation content such as digital 2D maps, 3D route visualizations (presented as continuous media from a first person perspective) and graphical directional arrows. It is well-established that visitors within complex building architectures (e.g. hospitals) often face challenges in finding their way and are limited to using traditional static signage or asking others for directions. Recent developments in mobile and pervasive technology however, are enabling a range of possibilities and augmenting the way in which users receive digital navigation support. Here, we discuss a formative study involving 16 participants using the prototype Hermes2 Navigation System in order to inform the development of a useful and usable interactive indoor navigation system.

In many mid- to large-sized cities public maps are ubiquitous. One can also find a great number of maps in parks or near hiking trails. Public maps help to facilitate orientation and provide special information to not only tourists but also to locals who just want to look up an unfamiliar place while on the go. These maps offer many advantages compared to mobile maps from services like Google Maps Mobile or Nokia Maps. They often show local landmarks and sights that are not shown on standard digital maps. Often these 'You are here' (YAH) maps are adapted to a special use case, e.g. a zoo map or a hiking map of a certain area. Being designed for a fashioned purpose these maps are often aesthetically well designed and their usage is therefore more pleasant. In this paper we present a novel technique and application called PhotoMap that uses images of 'You are here' maps taken with a GPS-enhanced mobile camera phone as background maps for on-the-fly navigation tasks. We discuss different implementations of the main challenge, namely helping the user to properly georeference the taken image with sufficient accuracy to support pedestrian navigation tasks. We present a study that discusses the suitability of various public maps for this task and we evaluate if these georeferenced photos can be used for navigation on GPS-enabled devices.

There is a significant disparity between wayfinding support services available in outdoor and in-building locations. Services such as Google Maps and in-car GPS allow users to examine unknown outdoor locations in advance as well as receive guidance en-route. In contrast, there is relatively little digital technology to support users in complex building architectures, e.g. institution buildings where users are generally limited to using traditional signage or asking for directions at the reception. However, recent advances in pervasive digital display technology are enabling a new range of possibilities and are making this topic increasingly subject to study. In this paper, we describe five formative studies involving 39 participants using situated digital displays, a Person Locator Kiosk, and personal mobile devices. We report our findings by gaining insights and feedback from users in order to develop wayfinding assistance for visitors in an in-building environment.