Gordon Kurtenbach

The limits of expert performance using hierarchic marking menus

A marking menu allows a user to perform a menu selection by either popping-up a radial (or pie) menu, or by making a straight mark in the direction of the desired menu item without popping-up the menu. A hierarchic marking menu uses hierarchic radial menus and “zig-zag” marks to select from the hierarchy. This paper experimentally investigates the bounds on how many items can be in each level, and how deep the hierarchy can be, before using a marking to select an item becomes too slow or prone to errors.

The design of a GUI paradigm based on tablets, two-hands, and transparency

An experimental GUI paradigm is presented which is based on the design goals of maximizing the amount of screen used for application data, reducing the amount that the UI diverts visual attentions from the application data, and increasing the quality of input. In pursuit of these goals, we integrated the non-standard UI technologies of multi-sensor tablets, toolglass, transparent UI components, and marking menus. We describe a working prototype of our new paradigm, the rationale behind it and our experiences introducing it into an existing application. Finally, we presents some ot the lessons learned: prototypes are useful to break the barriers imposed by conventional GUI design and some of their ideas can still be retrofitted seamlessly into products. Furthermore, the added functionality is not measured only in terms of user performance, but also by the quality of interaction, which allows artists to create new graphic vocabularies and graphic styles.

The Rockin'Mouse: integral 3D manipulation on a plane

A novel input device called the Rockin’Mouse is described and evaluated. The Rockin’Mouse is a four degree-of-freedom input device that has the same shape as a regular mouse except that the bottom of the Rockin’Mouse is rounded so that it can be tilted. This tilting can be used to control two extra degrees of freedom, thus making it suitable for manipulation in 3D environments. Like the regular mouse, the Rockin’Mouse can sense planar position and perform all the usual functions. However, in a 3D scene a regular mouse can only operate on 2 dimensions at a time and therefore manipulation in 3D requires a way to switch between dimensions. With the Rockin’Mouse, however, all the dimensions can be simultaneously controlled. In this paper we describe our design rationale behind the Rockin’Mouse, and present an experiment which compares the Rockin’Mouse to the standard mouse in a typical 3D interaction task. Our results indicate that the Rockin’Mouse is 30% faster and is a promising device for both 2D and 3D interaction.

Issues in combining marking and direct manipulation techniques

The direct manipulation paradigm has been effective in helping designers create easy to use mouse and keyboard based interfaces. The development of flat display surfaces and transparent tablets are now making possible interfaces where a user can write directly on the screen using a special stylus. The intention of these types of interfaces is to exploit user’s existing handwriting, mark-up and drawing skills while also providing the benefits of direct manipulation. This paper reports on a test bed program which we are using for exploring hand-marking types of interactions and their integration with direct manipulation interactions.

Exploring bimanual camera control and object manipulation in 3D graphics interfaces

We explore the use of the non-dominant hand to control a virtualcamera while the dominant hand performs other tasks in a virtual 3Dscene. Two experiments and an informal study are presented whichevaluate this interaction style by comparing it to the status-quounimanual interaction. In the first experiment, we find that for atarget selection task, performance using the bimanual technique was20% faster. Experiment 2 compared performance in a more complicatedobject docking task. Performance advantages are shown, however,only after practice. Free-form 3D painting was explored in the userstudy. In both experiments and in the user study participantsstrongly preferred the bimanual technique. The results alsoindicate that user preferences concerning bimanual interaction maybe driven by factors other than simple time-motion performanceadvantages.

The prevention of mode errors through sensory feedback

The use of different kinds of feedback in preventing mode errors was investigated. Two experiments examined the frequency of mode errors in a text-editing task where a mode error was defined as an attempt to issue navigation commands while in insert mode, or an attempt to insert text while in command mode. In Experiment 1, the effectiveness of kinesthetic versus visual feedback was compared in four different conditions: the use of keyboard versus foot pedal for changing mode (kinesthetic feedback), crossed with the presence or absence of visual feedback to indicate mode. The results showed both kinesthetic and visual feedback to be effective in reducing mode errors. However, kinesthetic was more effective than visual feedback both in terms of reducing errors and in terms of reducing the cognitive load associated with mode changes. Experiment 2 tested the hypothesis that the superiority of this kinesthetic feedback was due to the fact that the foot pedal required subjects actively to maintain insert mode. The results confirmed that the use of a nonlatching foot pedal for switching modes provided a more salient source of information on mode state than the use of a latching pedal. On the basis of these results, we argue that user-maintained mode states prevent mode errors more effectively than system-maintained mode states.

A confederation of tools for capturing and accessing collaborative activity

This paper presents a confederation of tools, called Coral, that combine to support the real-time capture of and subsequent access to informal collaborative activities. The tools provide the means to initiate digital multimedia recordings, a variety of methods to index those recordings, and ways to retrieve the indexed material in other settings. The current system emerged from a convergence of the WhereWereWe multimedia work, the Tivoli LiveBoard application, and the Inter-Language Unification distributed-object programming infrastructure. We are working with a specific user community and application domain, which has helped us shape a particular, demonstrably useful, configuration of tools and to get extensive real-world experience with them. This domain involves frequent discussion and decision-making meetings and later access of the captured records of those meetings to produce accurate documentation. Several aspects of Coral--the application tools, the architecture of the confederation, and the multimedia infrastructure--are described.

The Hotbox: efficient access to a large number of menu-items

The proliferation of multiple toolbars and UI widgetsaround the perimeter of application windows is an indication thatthe traditional GUI design of a single menubar is notsufficient to support large scale applications with numerousfunctions. In this paper we describe a new widget which is anenhancement of the traditional menubar which dramaticallyincreases menu-item capacity. This widget, called the Hotboxcombines several GUI techniques which are generally usedindependently: accelerator keys, modal dialogs, pop-up/pull downmenus, radial menus, marking menus and menubars. These techniquesare fitted together to create a single, easy to learn yet fast tooperate GUI widget which can handle significantly moremenu-items than the traditional GUI menubar. Wedescribe the design rationale of the Hotbox and its effectivenessin a large scale commercial application. While the Hotbox wasdeveloped for a particular application domain, the widget itselfand the design rationale are potentially useful in otherdomains.

Boom chameleon: simultaneous capture of 3D viewpoint, voice and gesture annotations on a spatially-aware display

We introduce the Boom Chameleon, a novel input/output device consisting of a flat-panel display mounted on a tracked mechanical boom. The display acts as a physical window into 3D virtual environments, through which a one-to-one mapping between real and virtual space is preserved. The Boom Chameleon is further augmented with a touch-screen and a microphone/speaker combination. We present a 3D annotation application that exploits this unique configuration in order to simultaneously capture viewpoint, voice and gesture information. Design issues are discussed and results of an informal user study on the device and annotation software are presented. The results show that the Boom Chameleon annotation facilities have the potential to be an effective, easy to learn and operate 3D design review system.

Large displays in automotive design

Explores the traditional and current uses of large displays in automotive design and presents new applications that make innovative use of large-format electronic displays. The development of our applications has highlighted several issues and challenges for the future. Perhaps the overriding issue is that, ultimately, the story is about interaction, not displays. For the system to be of value, its generally not enough simply to present information. Viewers must be able to create, manipulate, explore and annotate the displayed image. Furthermore, the displays location, who uses it, what its used for and how its used are all critical in determining value.