Marco Winckler

A formal description of multimodal interaction techniques for immersive virtual reality applications

Nowadays, designers of Virtual Reality (VR) applications are faced with the choice of a large number of different input and output devices leading to a growing number of interaction techniques. Usually VR interaction techniques are described informally, based on the actions users can perform within the VR environment. At implementation time, such informal descriptions (made at design time) yield to ambiguous interpretations by the developers. In addition, informal descriptions make it difficult to foresee the impact throughout the application of a modification of the interaction techniques. This paper discusses the advantages of using a formal description technique (called ICO) to model interaction techniques and dialogues for VR applications. This notation is presented via a case study featuring an immersive VR application. The case study is then used to show, through analysis of models, how the formal notation can help to ensure the usability, reliability and efficiency of virtual reality systems.

A model-based approach for supporting engineering usability evaluation of interaction techniques

This paper offers a contribution for engineering interaction techniques by proposing a model-based approach for supporting usability evaluation. This approach combines different techniques including formal analysis of models, simulation and, in particular, analysis of log data in a model-based environment. This approach is integrated in a process and is supported by a model-based CASE tool for modeling, simulation and evaluation of interactive systems. A case study illustrates the approach and operation of the tool. The results demonstrate that the log data at model level can be used not only to identify usability problems but also to identify where to operate changes to these models in order to fix usability problems. Finally we show how the analysis of log data allows the designer to easily shape up the interaction technique (as the results of log analysis are presented at the same abstraction level of models). Such as an approach offers an alternative to user testing that are very difficult to configure and to interpret especially when advanced interaction techniques are concerned

Supporting Usability Evaluation of Multimodal Man-Machine Interfaces for Space Ground Segment Applications Using Petri nets Based Formal Specification

This paper describes the issues raised by the evaluation of multimodal interfaces in the field of command and control workstations. Design, specification, verification and certification issues for such Man-Machine Interfaces (MMIs) have been already identified as critical activities. This paper focuses on the issues raised by evaluation of their usability evaluation. We first present a formalism (Interactive Cooperative Objects) and its related case tool (PetShop) for the specification of such MMIs and then show how the models built can support the usability evaluation phase. As a case study we present a multimodal interaction for 3D navigation in a 3D satellite model.

Tasks and scenario-based evaluation of information visualization techniques

Usability evaluation of an information visualization technique can only be done by the joint evaluation of both the visual representation and the interaction techniques. This work proposes task models as a key element for carrying out such evaluations in a structured way. We base our work on a taxonomy abstracting from rendering functions supported by information visualization techniques. CTTE is used to model these abstract visual tasks as well as to generate scenarios from this model for evaluation purposes. We conclude that the use of task models allows generating test scenarios which are more effective than informal and unstructured evaluations.

Capture and evolution of web requirements using webspec

Developing Web applications is a complex and time consuming process that involves different kind of people, ranging from customers to developers. Requirement artefacts play an important role as they are used by these people to perform their daily activities. However, state of the art in requirement management for Web applications disregards valuable features that tend to improve the development process, such as quick validation during elicitation, automatic requirement validation on the final application and useful change management support. To tackle these problems we introduce WebSpec, a requirement artefact for specifying interaction and navigation features in Web applications. We show its use through the development of an example application in the social networking area, and its implementation as an Eclipse plugin.

Model-Based Evaluation: A New Way to Support Usability Evaluation of Multimodal Interactive Applications

Multimodal interfaces are becoming more common, even in the field of safety critical interactive software, mainly due to the naturalness of the interaction that increases the bandwidth between the user and the system they are interacting with. However, the specificities of multimodal interactive systems make it difficult to gather information from the use of modalities and to extract from this information recommendations for improving the multimodal user interfaces. This chapter aims at presenting how abstract information described in models can be fruitfully exploited to improve the quality of evaluations of multimodal interfaces. The approach presented in this chapter combines model-based verification (based on simulation scenario extraction generated from models) and empirical methods for usability evaluation. Our aim is to try to bring together two separated (and often opposite) issues, such as usability and reliability, into the development of safety critical systems. This approach is illustrated via a Space Ground System of a satellite control room, whose multimodal interaction technique is fully described by the means of formal models.

SWCEditor: A Model-Based Tool for Interactive Modelling of Web Navigation

In spite of the apparent facility of building Web pages using current visual environments, the development on the Web application remains a complex task. As for other complex software one possible and promising way of dealing with this complexity is model-based approach. In this paper we present SWCEditor, a model-based tool (exploiting the StateWebCharts notation) aiming at supporting designers to build navigation models of Web applications. The StateWebCharts (SWC) notation is a formalism that provides abstract mechanisms to build navigation models of Web applications. This paper presents the SWCEditor, a tool supporting the creation, edition, visualisation and simulation of SWC models.

Cascading Dialog Modeling with UsiXML

This paper discusses multi-level dialog specifications for user interfaces of multi-target interactive systems and it proposes a step-wise method that combines a transformational approach for model-to-model derivation and an interactive editing of dialog models for tailoring the derived models. This method provides a synthesis of existing solutions for dialog modeling using a XML-based User Interface Description Language, UsiXML, along with State WebCharts notation for expressing the dialog at a high level of abstraction. Our aim is to push forward the design and reuse of dialog specifications throughout several levels of abstraction ranging from task and domain models until the final user interface thanks to a mechanism based on cascading style sheets. In this way, it is expected that the dialog properties are not only inherited from one level to another but also are made much more reusable than in the past.

Towards a Library of Workflow User Interface Patterns

A collection of user interface design patterns for workflow infor ma tion systems is presented. Each Workflow User Interface Pattern (WUIP) is characterized by properties expressed in the PLML markup language for expressing patterns and augmented by additional attributes and models at tached to the pattern: the abstract user interface and the corresponding task model. These models are specified in a User Interface Description Langua ge. All WUIPs are stored in a library and can be retrieved within a workflow editor that links each workflow pattern to its corresponding WUIP, thus giving rise to a user interface for each workflow pattern. The software then gathers these UIs and the ones corresponding to workflow tasks into a user interface flow, a new concept introduced for specifying the intertwining of interfaces used by workers and the workflow manager in a single workflow.

Model-based support for specifying eService eGovernment applications

Model-based approaches are a suitable alternative to cope with the increasing complexity of eServices made available in the last years by eGovernment applications. However, up to now, only a few studies have investigated which are the requirements for notations and tools devoted to support eService modeling. The main goal of this paper is to make a state of knowledge on the specification of user activity and processes in eGovernment eServices. Our results advocated for a hybrid approach for modeling combining task models and process models.