Tovi Grossman

Hover widgets: using the tracking state to extend the capabilities of pen-operated devices

We present Hover Widgets, a new technique for increasing the capabilities of pen-based interfaces. Hover Widgets are implemented by using the pen movements above the display surface, in the tracking state. Short gestures while hovering, followed by a pen down, access the Hover Widgets, which can be used to activate localized interface widgets. By using the tracking state movements, Hover Widgets create a new command layer which is clearly distinct from the input layer of a pen interface. In a formal experiment Hover Widgets were found to be faster than a more traditional command activation technique, and also reduced errors due to divided attention.

Multi-finger gestural interaction with 3d volumetric displays

Volumetric displays provide interesting opportunities and challenges for 3D interaction and visualization, particularly when used in a highly interactive manner. We explore this area through the design and implementation of techniques for interactive direct manipulation of objects with a 3D volumetric display. Motion tracking of the users fingers provides for direct gestural interaction with the virtual objects, through manipulations on and around the displays hemispheric enclosure. Our techniques leverage the unique features of volumetric displays, including a 360° viewing volume that enables manipulation from any viewpoint around the display, as well as natural and accurate perception of true depth information in the displayed 3D scene. We demonstrate our techniques within a prototype 3D geometric model building application.

A survey of software learnability: metrics, methodologies and guidelines

It is well-accepted that learnability is an important aspect of usability, yet there is little agreement as to how learnability should be defined, measured, and evaluated. In this paper, we present a survey of the previous definitions, metrics, and evaluation methodologies which have been used for software learnability. Our survey of evaluation methodologies leads us to a new question-suggestion protocol, which, in a user study, was shown to expose a significantly higher number of learnability issues in comparison to a more traditional think-aloud protocol. Based on the issues identified in our study, we present a classification system of learnability issues, and demonstrate how these categories can lead to guidelines for addressing the associated challenges.

GamiCAD: a gamified tutorial system for first time autocad users

We present GamiCAD, a gamified in-product, interactive tutorial system for first time AutoCAD users. We introduce a software event driven finite state machine to model a users progress through a tutorial, which allows the system to provide real-time feedback and recognize success and failures. GamiCAD provides extensive real-time visual and audio feedback that has not been explored before in the context of software tutorials. We perform an empirical evaluation of GamiCAD, comparing it to an equivalent in-product tutorial system without the gamified components. In an evaluation, users using the gamified system reported higher subjective engagement levels and performed a set of testing tasks faster with a higher completion ratio.

The design and evaluation of selection techniques for 3D volumetric displays

Volumetric displays, which display imagery in true 3D space, are a promising platform for the display and manipulation of 3D data. To fully leverage their capabilities, appropriate user interfaces and interaction techniques must be designed. In this paper, we explore 3D selection techniques for volumetric displays. In a first experiment, we find a ray cursor to be superior to a 3D point cursor in a single target environment. To address the difficulties associated with dense target environments we design four new ray cursor techniques which provide disambiguation mechanisms for multiple intersected targets. Our techniques showed varied success in a second, dense target experiment. One of the new techniques, the depth ray, performed particularly well, significantly reducing movement time, error rate, and input device footprint in comparison to the 3D point cursor.

Pointing at trivariate targets in 3D environments

We investigate pointing in true 3D environments where the target size varies in three spatial dimensions. We also study the effect of the users physical movement angle on pointing performance. Results show that target size dimension along the primary axis of movement has a greater impact on performance than the other two dimensions. Movement angle also significantly affects performance, and changes the relative impact of the three target dimensions. Building upon recent results in the modeling of bivariate pointing, we propose and validate a new model that describes pointing at trivariate targets. This model also accounts for movement angle, and outperforms previously published models.

Chronicle: capture, exploration, and playback of document workflow histories

We describe Chronicle, a new system that allows users to explore document workflow histories. Chronicle captures the entire video history of a graphical document, and provides links between the content and the relevant areas of the history. Users can indicate specific content of interest, and see the workflows, tools, and settings needed to reproduce the associated results, or to better understand how it was constructed to allow for informed modification. Thus, by storing the rich information regarding the documents history workflow, Chronicle makes any working document a potentially powerful learning tool. We outline some of the challenges surrounding the development of such a system, and then describe our implementation within an image editing application. A qualitative user study produced extremely encouraging results, as users unanimously found the system both useful and easy to use.

The design and evaluation of multitouch marking menus

Despite the considerable quantity of research directed towards multitouch technologies, a set of standardized UI components have not been developed. Menu systems provide a particular challenge, as traditional GUI menus require a level of pointing precision inappropriate for direct finger input. Marking menus are a promising alternative, but have yet to be investigated or adapted for use within multitouch systems. In this paper, we first investigate the human capabilities for performing directional chording gestures, to assess the feasibility of multitouch marking menus. Based on the positive results collected from this study, and in particular, high angular accuracy, we discuss our new multitouch marking menu design, which can increase the number of items in a menu, and eliminate a level of depth. A second experiment showed that multitouch marking menus perform significantly faster than traditional hierarchal marking menus, reducing acquisition times in both novice and expert usage modalities.

Creating principal 3D curves with digital tape drawing

Previous systems have explored the challenges of designing an interface for automotive styling which combine the metaphor of 2D drawing using physical tape with the simultaneous creation and management of a corresponding virtual 3D model. These systems have been limited to only 2D planar curves while typically the principal characteristic curves of an automotive design are three dimensional and non-planar. We present a system which addresses this limitation. Our system allows a designer to construct these non-planar 3D curves by drawing a series of 2D curves using the 2D tape drawing technique and interaction style. These results are generally applicable to the interface design of 3D modeling applications and also to the design of arms length interaction on large scale display systems

YouMove: enhancing movement training with an augmented reality mirror

YouMove is a novel system that allows users to record and learn physical movement sequences. The recording system is designed to be simple, allowing anyone to create and share training content. The training system uses recorded data to train the user using a large-scale augmented reality mirror. The system trains the user through a series of stages that gradually reduce the users reliance on guidance and feedback. This paper discusses the design and implementation of YouMove and its interactive mirror. We also present a user study in which YouMove was shown to improve learning and short-term retention by a factor of 2 compared to a traditional video demonstration.