Our work extends contemporary research into visualizations and related applications for automobiles. Focusing on external car bodies as a design space we introduce the External Automotive Displays (EADs), to provide visualizations that can share context and user-specific information as well as offer opportunities for direct and mediated interaction between users and automobiles. We conducted a design study with interaction designers to explore design opportunities on EADs to provide services to different road users; pedestrians, passengers, and drivers of other vehicles. Based on the design study, we prototyped four EADs in virtual reality (VR) to demonstrate the potential of our approach. This paper contributes our vision for EADs, the design and VR implementation of a few EAD prototypes, a preliminary design critique of the prototypes, and a discussion of the possible impact and future usage of external automotive displays.

We present decal-lenses, a new interaction technique that extends the concept of magic lenses to augment and manage multivariate visualizations on arbitrary surfaces. Our object-space lenses follow the surface geometry and allow the user to change the point of view during data exploration while maintaining a spatial reference to positions where one or more lenses were placed. Each lens delimits specific regions of the surface where one or more attributes can be selected or combined. Similar to 2D lenses, the user interacts with our lenses in real-time, switching between different attributes within the lens context. The user can also visualize the surface data representations from the point of view of each lens by using local cameras. To place lenses on surfaces of intricate geometry, such as the human brain, we introduce the concept of support surfaces for designing interaction techniques. Support surfaces provide a way to place and interact with the lenses while avoiding holes and occluded regions during data exploration. We further extend decal-lenses to arbitrary regions using brushing and lassoing operations. We discuss the applicability of our technique and present several examples where our lenses can be useful to create a customized exploration of multivariate data on surfaces.

Abstract In this paper, we present a novel illustrative multivariate visualization for geological modelling to assist geologists and reservoir engineers in visualizing multivariate datasets in superimposed representations, in contrast to the single‐attribute visualizations supported by commercial software. Our approach extends the use of decals from a single surface to 3D irregular grids, using the layering concept to represent multiple attributes. We also build upon prior work to augment the design and implementation of different geological attributes (namely, rock type, porosity, and permeability). More specifically, we propose a new sampling strategy to generate decals for porosity on the geological grid, a hybrid visualization for permeability which combines 2D decals and 3D ellipsoid glyphs, and a perceptually‐based design that allows us to visualize additional attributes (e.g., oil saturation) while avoiding visual interference between layers. Furthermore, our visual design draws from traditional geological illustrations, facilitating the understanding and communication between interdisciplinary teams. An evaluation by domain experts highlights the potential of our approach for geological modelling and interpretation in this complex domain.

Do-it-yourself (DIY) inspired activities have gained popularity as a means of creative expression and self-directed learning. However, DIY culture is difficult to implement in places with limited technology infrastructure and traditional learning cultures. Our goal is to understand how learners in such a setting react to DIY activities. We present observations from a physical computing workshop with 12 students (13-15 years old) conducted at a high school in India. We observed unique challenges for these students when tackling DIY activities: a high monetary and psychological cost to exploration, limited independent learning resources, difficulties with finding intellectual courage and assumed technical language proficiency. Our participants, however, overcome some of these challenges by adopting their own local strategies: resilience, nonverbal and verbal learning techniques, and creating documentation and fallback circuit versions. Based on our findings, we discuss a set of lessons learned about makerspaces in a context with socio-technical challenges.

We introduce the use of decals for multivariate visualization design. Decals are visual representations that are used for communication; for example, a pattern, a text, a glyph, or a symbol, transferred from a 2D-image to a surface upon contact. By creating what we define as decal-maps, we can design a set of images or patterns that represent one or more data attributes. We place decals on the surface considering the data pertaining to the locations we choose. We propose a (texture mapping) local parametrization that allows placing decals on arbitrary surfaces interactively, even when dealing with a high number of decals. Moreover, we extend the concept of layering to allow the co-visualization of an increased number of attributes on arbitrary surfaces. By combining decal-maps, color-maps and a layered visualization, we aim to facilitate and encourage the creative process of designing multivariate visualizations. Finally, we demonstrate the general applicability of our technique by providing examples of its use in a variety of contexts.

We present the results of a pilot study that investigates if and how people judge the trustworthiness of a robot during social Human-Robot Interaction (sHRI). Current research in sHRI has observed that people tend to interact with robots socially. However, results from neuroscience suggests people use different cognitive mechanisms interacting with robots than they do with humans, leading to a debate about whether people truly perceive robots as social entities. Our paper focuses on one aspect of this debate, by examining trustworthiness between people and robots using behavioral economics' ‘Trust Game’ scenario. Our pilot study replicates a trust game scenario, where a person invests money with a robot trustee in hopes they will receive a larger sum (trusting the robot to give more back), then gets a chance to invest once more. Our qualitative analysis of investing behavior and interviews with participants suggests that people may follow a human-robot (h-r) trust model that is quite similar to the human-human trust model. Our results also suggest a possible resolution to the sHRI and Neuroscience debate: people try to interact socially with robots, but due to lack of common social cues, they draw from social experience, or create new experiences by actively exploring the robot behavior.

This paper presents a set of lessons learnt from introducing maker culture and DIY paradigms to 'at-risk' students (age 12-14). Our goal is to engage 'at-risk' students through maker culture activities. While improved technology literacy is one of the outcomes we also wanted the learners to use technology to realize concepts and ideas, and to gain freedom of thinking similar to creators, artists and designers. We present our study and a set of high level suggestions to enable thinking about how maker culture activities can facilitate engagement and creative use of technology by 1) thinking about creativity in task, 2) facilitating different entry points, 3) the importance of personal relevance, and 4) relevance to education.

We present Flying Frustum, a 3D spatial interface that enables control of semi-autonomous UAVs (Unmanned Aerial Vehicles) using pen interaction on a physical model of the terrain, and that spatially situates the information streaming from the UAVs onto the physical model. Our interface is based on a 3D printout of the terrain, which allows the operator to enter goals and paths to the UAV by drawing them directly on the physical model. In turn, the UAV's streaming reconnaissance information is superimposed on the 3D printout as a view frustum, which is situated according to the UAV's position and orientation on the actual terrain. We argue that Flying Frustum's 3D spatially situated interaction can potentially help improve human-UAV awareness and enhance the overall situational awareness. We motivate our design approach for Flying Frustum, discuss previous related work in CSCW and HRI, present our preliminary prototype using both handheld and headset augmented reality interfaces, reflect on Flying Frustum's strengths and weaknesses, and discuss our plans for future evaluation and prototype improvements.

Given a set of symmetric/antisymmetric filter vectors containing only regular multiresolution filters, the method we present in this article can establish a balanced multiresolution scheme for images, allowing their balanced decomposition and subsequent perfect reconstruction without the use of any extraordinary boundary filters. We define balanced multiresolution such that it allows balanced decomposition i.e. decomposition of a high-resolution image into a low-resolution image and corresponding details of equal size. Such a balanced decomposition makes on-demand reconstruction of regions of interest efficient in both computational load and implementation aspects. We find this balanced decomposition and perfect reconstruction based on an appropriate combination of symmetric/antisymmetric extensions near the image and detail boundaries. In our method, exploiting such extensions correlates to performing sample (pixel/voxel) split operations. Our general approach is demonstrated for some commonly used symmetric/antisymmetric multiresolution filters. We also show the application of such a balanced multiresolution scheme in real-time focus+context visualization.

We believe that every physical entity has a set of attributes that defines the degree of how creatively it can be used. For example, the affordances, abstractness and modular nature of Lego™ blocks allows them to take on different forms of expression that showcases varying levels of human creativity (e.g. building alphabets, creating homes etc.). Similarly, when a DIY designer uses bottles to build houses, it projects his creative skills, but at the same time it speaks about the materiality, affordances and embodiment of the bottle which lends itself readily to creative and novel interaction design efforts. This theory, that every entity has a set of attributes that allows them to lend themselves more or less readily to creative and novel interactive design explorations is what we call explorances and is the focus of our proposed work.

Multidimensional projection techniques provide an appealing approach for multivariate data analysis, for their ability to translate high-dimensional data into a low-dimensional representation that preserves neighborhood information. In recent years, pushed by the ever increasing data complexity in many areas, numerous advances in such techniques have been observed, primarily in terms of computational efficiency and support for interactive applications. Both these achievements were made possible due to the introduction of the concept of control points, which are used in many different multidimensional projection techniques. However, little attention has been drawn towards the process of control points selection. In this work we propose a novel multidimensional projection technique based on radial basis functions (RBF). Our method uses RBF to create a function that maps the data into a low-dimensional space by interpolating the previously calculated position of control points. We also present a built-in method for the control points selection based on "forward-selection" and "Orthogonal Least Squares" techniques. We demonstrate that the proposed selection process allows our technique to work with only a few control points while retaining the projection quality and avoiding redundant control points.

In this paper, we present a view of robots as physical agents submitting to a static infrastructure, allowing a computerized static system to use the robot as a dynamic puppet, which is a social agent that can communicate on physical and social terms with its human users and visitors. We demonstrate our approach with Ningy? of the CAVE, a prototype designed to allow a virtual reality CAVE facility to introduce its capabilities to human users and visitors. Through the robot, the CAVE is able to highlight capabilities and uses of the facility through performance, showmanship and physical actions to create an engaging interaction that conveys an overview of the facility and demonstrates its key functionalities. We examine the quality of the resulting engagement with preliminary reflection by several human visitors to our CAVE system. We believe that viewing robots as components of a greater and more capable computerized ecosystem is a less explored research path in social human-robot interaction, and hope that our Ningy? of the CAVE prototype could set the stage and inform some of the future research on this topic.

In this paper we present a novel mixed reality tracking system for collaborative tabletop applications that uses decorative markers and embedded application markers to create a continuous and seamless tracking space for mobile devices. Users can view and interact with mixed reality datasets on their mobile device, such as a tablet or smartphone, from distances both far and very near to the tabletop. We implement the tracking system in the context of a collaborative reservoir engineering tool that brings together many experts who need a private workspace to interact with unique datasets, which is supported by our system.

In this paper, we introduce a novel framework for the compositing of interactively rendered 3D layers tailored to the needs of scientific illustration. Currently, traditional scientific illustrations are produced in a series of composition stages, combining different pictorial elements using 2D digital layering. Our approach extends the layer metaphor into 3D without giving up the advantages of 2D methods. The new compositing approach allows for effects such as selective transparency, occlusion overrides, and soft depth buffering. Furthermore, we show how common manipulation techniques such as masking can be integrated into this concept. These tools behave just like in 2D, but their influence extends beyond a single viewpoint. Since the presented approach makes no assumptions about the underlying rendering algorithms, layers can be generated based on polygonal geometry, volumetric data, point-based representations, or others. Our implementation exploits current graphics hardware and permits real-time interaction and rendering.

We describe a new method for controlling a group of robots in three-dimensional (3D) space using a tangible user interface called the 3D Tractus. Our interface maps the task space into an interactive 3D space, allowing a single user to intuitively monitor and control a group of robots. We present the use of the interface in controlling a group of virtual software bots and a physical Sony AIBO robot dog in an urban search and rescue environment involving a bomb hidden inside of a building. We also describe a comparative user study we performed where participants were asked to use both the 3D physical interface and a traditional 2D graphical user interface in order to try and demonstrate the benefits and drawbacks of each approach for HRI tasks.

This paper describes, Napkin Sketch, a 3D sketching interface which attempts to support sketch-based artistic expression in 3D, mimicking some of the qualities of conventional sketching media and tools both in terms of physical properties and interaction experience. A portable tablet PC is used as the sketching platform, and handheld mixed reality techniques are employed to allow 3D sketches to be created on top of a physical napkin. Intuitive manipulation and navigation within the 3D design space is achieved by visually tracking the tablet PC with a camera and mixed reality markers. For artistic expression using sketch input, we improve upon the projective 3D sketching approach with a one stroke sketch plane definition technique. This coupled with the hardware setup produces a natural and fluid sketching experience.

We present an illustrative visualization system for real-time and high quality rendering of clinical volumetric medical data. Our technique is inspired by a medical illustration technique for depicting contextual close-up views of selected regions of interest where internal anatomical features are rendered in high detail. Our method integrates four important components: decimation of original volume for interactivity, B-spline subdivision for super-resolution rendering, fast gradient quantization technique for feature extraction and GPU fragment shaders for gradient dependent rendering and transfer functions. Examples with clinical CT and MRI data demonstrate the capabilities of our system.

We present new techniques for rendering hierarchical, skeletal implicit models in several pen-and-ink styles. Our approach extracts silhouette strokes and lines following local shape features, such as those caused by CSG junc-tions. To this end, it uses particle systems to find interesting areas on the surface and perform stroke stylization guided by local shape features. Also, it removes hidden lines either by applying a surfel technique for rapid proto-typing, or more accurately by using ray tracing. Examples from simple to complex models illustrate the capabilities of our system.

This paper introduces a method for creating naturally varied plants from a given basic plant model. Previous techniques create variation in plants by introducing local randomness to the plant model's description. However, randomness is restricted by the model's parameterization and lack of correlation between local features making varying global properties (e.g. branch and stem curvature) difficult. We present a biologically−based method which mimics the underpinnings of variation in real plants. This method uses a feedback control system to simulate the biological growth mechanism by which a plant naturally responds to environmental factors. We show that our technique creates more realistically varied models by modelling growth responses to stimuli, and provides a method for quickly creating numerous similar models, none of which are exactly alike.

This work presents a new algorithm and technique for rendering triangular surfaces in pen-and-ink edge-based strokes. Our technique integrates two very important illustration strategies for depicting shape features: selection of drawing direction and the use of light. Drawing direction is given by four stroke directional fields. For lighting, we introduce the idea of "spotlight silhouettes" for fast illumination computation, with target tone matched by adaptive stroke length adjustment. Stroke style is achieved by path perturbation and noise-based weight control. Our technique also allows visual effects of reverse tone values and depth cueing. Examples with models from anatomy and archeology demonstrate the capabilities of our system.

Abstract Drawings made with precise pen strokes accurately reveal the geometric forms that give subjects their characteristicshape. We present a system for non‐photorealistic rendering of precise drawing strokes over dense 3Dtriangle meshes with arbitrary topology. During an automatic pre‐process, we construct an extended version ofthe edge‐buffer data structure to allow the calculation of shape measures at each mesh edge, by adapting numericalmethods used in geomorphology. At runtime, feature edges related to shape measures are extracted andrendered as strokes with varying thickness and pen marking styles. Stroke thickness is automatically adjusted byconsidering surface curvature. Pen marking styles and visual effects of ink distribution are both controlled by theuser. We demonstrate precise drawing strokes over complex meshes revealing a variety of shape characteristics.

Abstract We present a method for rendering 3D models in the traditionalline‐drawing style used in artistic and scientificillustrations. The goal is to suggest the 3D shape of the objectsusing a small number of lines drawn with carefullychosen line qualities. The system combines several known techniquesinto a simple yet effective non‐photorealisticline renderer. Feature edges related to the outline and interiorof a given 3D mesh are extracted, segmented, andsmoothed, yielding chains of lines with varying path, length, thickness,gaps, and enclosures. The paper includessample renderings obtained for a variety of models.

This paper presents models for graphite pencil, drawing paper, blenders, and kneaded eraser that produce realistic looking pencil marks, textures, and tones. Our models are based on an observation of how lead pencils interact with drawing paper, and on the absorptive and dispersive properties of blenders and erasers interacting with lead material deposited over drawing paper. The models consider parameters such as the particle composition of the lead, the texture of the paper, the position and shape of the pencil materials, and the pressure applied to them. We demonstrate the capabilities of our approach with a variety of images and compare them to digitized pencil drawings. We also present image‐based rendering results implementing traditional graphite pencil tone rendering methods.

Researchers in non‐photorealistic rendering have investigated the display of three‐dimensional worlds using various display models. In particular, recent work has focused on the modeling of traditional artistic media and styles such as pen‐and‐ink illustration and watercolor painting. By providing 3D rendering systems that use these alternative display models users can generate traditional illustration renderings of their three‐dimensional worlds. In this paper we present our graphite pencil 3D renderer. We have broken the problem of simulating pencil drawing down into four fundamental parts: (1) simulating the drawing materials (graphite pencil and drawing paper, blenders and kneaded eraser), (2) modeling the drawing primitives (individual pencil strokes and mark‐making to create tones and textures), (3) simulating the basic rendering techniques used by artists and illustrators familiar with pencil rendering, and (4) modeling the control of the drawing composition. Each part builds upon the others and is essential to developing the framework for higher‐level rendering methods and tools. In this paper we present parts 2, 3, and 4 of our research. We present non‐photorealistic graphite pencil rendering methods for outlining and shading. We also present the control of drawing steps from preparatory sketches to finished rendering results. We demonstrate the capabilities of our approach with a variety of images generated from 3D models.