Philip D. Gray

Putting the feel in ’look and feel‘

Haptic devices are now commercially available and thus touch has become a potentially realistic solution to a variety of interaction design challenges. We report on an investigation of the use of touch as a way of reducing visual overload in the conventional desktop. In a two-phase study, we investigated the use of the PHANToM haptic device as a means of interacting with a conventional graphical user interface. The first experiment compared the effects of four different haptic augmentations on usability in a simple targeting task. The second experiment involved a more ecologically-oriented searching and scrolling task. Results indicated that the haptic effects did not improve users performance in terms of task completion time. However, the number of errors made was significantly reduced. Subjective workload measures showed that participants perceived many aspects of workload as significantly less with haptics. The results are described and the implications for the use of haptics in user interface design are discussed.

Modelling and Using Sensed Context Information in the Design of Interactive Applications

We present a way of analyzing sensed context information formulated to help in the generation, documentation and assessment of the designs of context-aware applications. Starting with a model of sensed context that accounts for the particular characteristics of sensing, we develop a method for expressing requirements for sensed context information in terms of relevant quality attributes plus properties of the sensors that supply the information. We demonstrate on an example how this approach permits the systematic exploration of the design space of context sensing along dimensions pertinent to software development. Returning to our model of sensed context, we examine how it can be supported by a modular software architecture for context sensing that promotes separation between context sensing, user interaction, and application concerns.

Temporal aspects of tasks in the user action notation

The need for communication among a multiplicity of cooperating roles in user interface development translates into the need for a common set of interface design representation techniques. The important difference between design of the interaction part of the interface and design of the interface software calls for representation techniques with a behavioral view - a view that focuses on user interaction rather than on the software. The User Action Notation (UAN) is a user- and task-oriented notation that describes physical (and other) behavior of the user and interface as they perform a task together. The primary abstraction of the UAN is a user task. The work reported here addresses the need to identify temporal relationships within user task descriptions and to express explicitly and precisely how designers view temporal relationships among those tasks. Drawing on simple temporal concepts such as events in time and preceding and overlapping of time intervals, we identify basic temporal relationships among tasks: sequence, waiting, repeated disjunction, order independence, interruptibility, one-way interleavability, mutual interleavability, and concurrency. The UAN temporal relations, through the notion of modal logic, offer an explicit and precise representation of the specific kinds of temporal behavior that can occur in asynchronous user interaction without the need to detail all cases that might result.

Teallach: a model-based user interface development environment for object databases

Abstract Model-based user interface development environments show promise for improving the productivity of user interface developers, and possibly for improving the quality of developed interfaces. While model-based techniques have previously been applied to the area of database interfaces, they have not been specifically targeted at the important area of object database applications. Such applications make use of models that are semantically richer than their relational counterparts in terms of both data structures and application functionality. In general, model-based techniques have not addressed how the information referenced in such applications is manifested within the described models, and is utilised within the generated interface itself. This lack of experience with such systems has led to many model-based projects providing minimal support for certain features that are essential to such data intensive applications, and has prevented object database interface developers in particular from benefiting from model-based techniques. This paper presents the Teallach model-based user interface development environment for object databases, describing the models it supports, the relationships between these models, the tool used to construct interfaces using the models and the generation of Java programs from the declarative models. Distinctive features of Teallach include comprehensive facilities for linking models, a flexible development method, an open architecture, and the generation of running applications based on the models constructed by designers.

The effect of age and font size on reading text on handheld computers

Though there have been many studies of computer based text reading, only a few have considered the small screens of handheld computers. This paper presents an investigation into the effect of varying font size between 2 and 16 point on reading text on a handheld computer. By using both older and younger participants the possible effects of age were examined. Reading speed and accuracy were measured and subjective views of participants recorded. Objective results showed that there was little difference in reading performance above 6 point, but subjective comments from participants showed a preference for sizes in the middle range. We therefore suggest, for reading tasks, that designers of interfaces for mobile computers provide fonts in the range of 8-12 point to maximize readability for the widest range of users.

Using Landmarks to Support Older People in Navigation

Although landmarks are an integral aspect of navigation, they have rarely been used within electronic navigation aids. This paper describes the design of a pedestrian navigation aid for a handheld computer, which guides the user along a route using photographs of landmarks, together with audio and text instructions that reference these landmarks. This aid was designed with older users in mind who often find their mobility hampered by declines in sensory, cognitive and motor abilities. It was tested against the standard paper map for the test area with both younger and older people and their performance and subjective workload were measured. The results show that such an aid can significantly outperform a paper-based map and that older people derive substantially more benefit from it than do younger people.

Affective feedback: an investigation into the role of emotions in the information seeking process

User feedback is considered to be a critical element in the information seeking process, especially in relation to relevance assessment. Current feedback techniques determine content relevance with respect to the cognitive and situational levels of interaction that occurs between the user and the retrieval system. However, apart from real-life problems and information objects, users interact with intentions, motivations and feelings, which can be seen as critical aspects of cognition and decision-making. The study presented in this paper serves as a starting point to the exploration of the role of emotions in the information seeking process. Results show that the latter not only interweave with different physiological, psychological and cognitive processes, but also form distinctive patterns, according to specific task, and according to specific user.

How can we best use landmarks to support older people in navigation

Although landmarks are an integral part of navigation, they have rarely been used explicitly within electronic pedestrian navigation aids. We describe a two-part study into the use of landmarks in such aids, using a set of field experiments. The first part investigated whether such devices can be effective for older adults (over 60 years old), who might particularly benefit from them due to declines in sensory, cognitive and motor abilities. The second part compared the effectiveness of different methods of presenting landmark information. We show that a pedestrian navigation aid based around landmarks is particularly useful for older people and demonstrate that text, speech and photographs are all effective ways of presenting landmark information, although speech on its own has some drawbacks. We found that different people prefer information to be presented in different modalities, indicating a need for personalisation, although multi-modality may also help to address this issue.

Solving multi-target haptic problems in menu interaction

While haptic feedback has been shown to enhance user performance and satisfaction in single target interactions in desktop user interfaces, it is not clear whether this will hold for more realistic, multi-target interactions. Here we present an experimental study of haptically enhanced menus. We evaluate a visual condition, a haptic condition and an adjusted haptic condition designed to support menu interactions. We conclude that thoughtful design can create multi-target haptic augmentations that provide performance benefits.

Guidelines for the Design of Haptic Widgets

Haptic feedback has been shown to improve user performance in Graphical User Interface (GUI) targeting tasks in a number of studies. These studies have typically focused on interactions with individual targets, and it is unclear whether the performance increases reported will generalise to the more realistic situation where multiple targets are presented simultaneously. This paper addresses this issue in two ways. Firstly two empirical studies dealing with groups of haptically augmented widgets are presented. These reveal that haptic augmentations of complex widgets can reduce performance, although carefully designed feedback can result in performance improvements. The results of these studies are then used in conjunction with the previous literature to generate general design guidelines for the creation of haptic widgets.