Smart assistive technologies are increasingly being used to support independent living. Occupational therapists perceive such technologies as useful to helping their clients become more independent in their everyday activities, particularly individuals having sustained a traumatic brain injury. However, adapting and configuring these technologies to meet each person's individual needs remain challenging. In this study, occupational therapists and computer scientists collaborate to develop a recommendation system designed to assist in configuring a smart assistive technology that helps people having sustained a traumatic brain injury cook safely. The relevance of the recommendations made by this case-based recommendation system was first evaluated by comparing the recommended assistant options with the selections of an expert occupational therapist. Then, we questioned the final users, i.e. occupational therapists, about the usefulness of such a system. This first prototype demonstrated promising results, with about 80% correct recommendations for selection (with an average percentage ranging from 77.0% to 86.2% depending on the threshold set for recommended functionalities, using a database of 16 cases). Additionally, the system was found to be robust against an unbalanced database and has been estimated as useful and relevant by end-users, who remain the final decisionmakers. The latter also expressed concerns and suggested improvements, which were incorporated early in the development process to enhance acceptance and facilitate the tool's integration into clinical practice. As a result, the tools and methods used by the multidisciplinary team led to the successful development of a generic human-centered recommendation system that can be used to personalize smart assistive technologies to each unique person's needs.

The goal of plasticity is to ensure usability continuity whatever the context of use. This context must be modeled into the system and possibly taken into account to adapt the final application. The difficulty to handle plasticity for 3D applications comes from the lack of solutions for developers and designers to model and take these constraints into account. This paper introduces new models designed to deal with plasticity for Virtual Reality (VR) and Augmented Reality (AR). These models are implemented in a software solution: 3DPlasticToolkit. It aims to provide a solution for developing 3D applications that can automatically fit any context of use. This context of use includes a set of 3D hardware and environmental constraints, such as user preferences and available interaction devices. 3DPlasticToolkit includes tools for modeling this context and for creating application components independently from it. We propose an adaptation engine based on a scoring algorithm to dynamically create the most suited 3D user interfaces according to the context of use at runtime. We use a furniture planning scenario to show how these adaptations can impact interactions and content presentation.

The aim of this article concerns adaptive and personalized navigation in a cultural heritage database. The theoretical grounding of the proposition relies on cognitive science, particularly constructivism and enaction. The navigation is conducted via an intelligent interface through a 3D living museum metaphor. The purpose of this interface is to recommend dynamic cultural heritage objects according to a user profile that is computed online from the interactions that a user has with these objects. To this end, objects are linked to semantic structures that represent relations between cultural heritage concepts. The user profile is described in terms of cultural heritage interests. A prototype of this principle is used to evaluate some of the basic hypotheses of this proposition.

A 3D user interface can be adapted in multiple ways according to each user’s needs, skills and preferences. Such adaptation can consist in changing the user interface layout or its interaction techniques. Personalization systems which are based on user models can automatically determine the configuration of a 3D user interface in order to fit a particular user. In this paper, we propose to explore the use of machine learning in order to propose a 3D selection interaction technique adapted to a target user. To do so, we built a dataset with 51 users on a simple selection application in which we recorded each user profile, his/her results to a 2D Fitts Law based pre-test and his/her preferences and performances on this application for three different interaction techniques. Our machine learning algorithm based on Support Vector Machines (SVMs) trained on this dataset proposes the most adapted interaction technique according to the user profile or his/her result to the 2D selection pre-test. Our results suggest the interest of our approach for personalizing a 3D user interface according to the target user but it would require a larger dataset in order to increase the confidence about the proposed adaptations.

We propose dynamic 3D plastic and redistributable technology (D3PART), a model to handle redistribution for 3D user interfaces. Redistribution consists in changing the components distribution of an interactive system across different dimensions such as, platform, display and user. Our work is based on previous models for the creation of 3D plastic user interfaces, interactive systems that can handle the context of use modifications while preserving usability. In our previous work, we proposed a task model, a device model and an application component model for the creation of plastic user interfaces that handle the 3D specificities. With D3PART, we extend these models in order to include redistribution capabilities. The final solution lets developers create applications where 3D content and tasks can be automatically redistributed across the different dimensions at runtime. The proposed redistribution process is based on a client-server architecture with a meta-user interface to control the redistribution configuration. In order to illustrate D3PART, we describe three different scenarios of redistribution between a tablet and a CAVE for a 3D application for furniture planning. Indeed, with an implementation of our model, we show how redistribution can be used at runtime to combine these platforms, to switch seamlessly from one platform to another, and lastly, how redistribution can be used to create a collaborative context of use.

This paper presents an intelligent user interface model dedicated to the exploration of complex databases. This model is implemented on a 3D metaphor: a virtual museum. In this metaphor, the database elements are embodied as museum objects. The objects are grouped in rooms according to their semantic properties and relationships and the rooms organization forms the museum. Rooms? organization is not predefined but defined incrementally by taking into account not only the relationships between objects, but also the user's centers of interest. The latter are evaluated in real-time through user interactions within the virtual museum. This interface allows for a personal reading and favors the discovery of unsuspected links between data. In this paper, we present our model's formalization as well as its application to the context of cultural heritage.

This paper presents a first step in the realization of an interactive user interface that organizes itself according to the user exploration of a database of cultural heritage objects. The first part makes a brief related works and lays the basis of this kind of system according to the enactive paradigm. The second part explains the mechanisms underlying the selforganization of the interface: keywords and cultural heritage objects are 3D graphical entities endowed with autonomous behaviors. They share a common virtual environment. Keywords behaviors are based on boïds flocking simulation while cultural heritage objects appears in an virtual museum which evolves and grows progressively. The result that is presented, is an incremental construction of an interactive and realtime 3D metaphor of virtual museum which is then user-specific.

In this paper we propose D3PART (Dynamic 3D Plastic And Redistribuable Technology), a model to handle redistribution for 3D user interfaces. Redistribution consists in changing the components distribution of an interactive system across different dimensions such as platform, display and user. We extend previous plasticity models with redistribution capabilities, which lets developers create applications where 3D content and interaction tasks can be automatically redistributed across the different dimensions at runtime.

This paper aims at reducing the ocular discomfort created by stereoscopy due to the effect called “frame cancellation”, for movies and interactive applications. This effect appears when a virtual object in negative parallax (front of the screen) is clipped by the screen edges; stereopsis cue lets observers perceive the object popping-out from the screen while occlusion cue provides observers with an opposite signal. Such a situation is not possible in the real world. This explains some visual discomfort for observers and leads to a poor depth perception of the scene. This issue is directly linked to the physical limitations of the display size that may not cover the entire field of view of the observer. To deal with these physical constraints we introduce two new methods in the context of interactive applications. The first method consists in two new rendering effects based on progressive transparency that aim to preserve the popping-out effect of the stereo. The second method focuses on adapting the interaction of the user, not allowing him to place virtual objects in an area subject to frame cancellation. Both methods have been evaluated and have shown a good efficiency in comparison to the state of the art approaches.

In this paper we propose a model to handle redistribution for 3D user interfaces. Redistribution consists in changing the components distribution of an interactive system across different dimensions such as platform, display and user. Our work is based on previous models that ease the creation of 3D plastic user interfaces, interactive systems that can handle context of use modifications while preserving usability. We extended these models in order to include redistribution capabilities. The final solution lets developers create applications where 3D content and interaction tasks can be automatically redistributed across the different dimensions at runtime. The proposed redistribution process includes an automatic detection of these platforms and a meta-user interface to control the redistribution granularity. In order to illustrate this model, we describe three different scenarios of redistribution between a tablet and a CAVE for a 3D application. We show how redistribution can be used at runtime to combine these platforms, to switch seamlessly from one platform to another one and last how redistribution can be used to create a collaborative context of use.

Plasticity of 3D user interfaces refers to their capabilities to automatically fit to a set of hardware and environmental constraints. This area of research has already been deeply explored in the domain of traditional 2D user interfaces. Besides, during the last decade, interest in 3D user interfaces has grown. Designers find with 3D user interfaces new ways to promote and interact with data, such as e-commerce websites, scientific data visualization, etc. Because of the wide variety of Virtual Reality (VR) and Augmented Reality (AR) applications in terms of hardware, data and target users, there is a real interest in solutions for automatic adaption in order to improve the user experience in any context while reducing the development costs. An adaptation is performed in reaction to different criteria defining a system such as the targeted hardware platform, the user's context and the structure and the semantic of the manipulated data. This adaptation can then impact the system in different ways, especially content presentation, interaction techniques modifications and eventually the current distribution of the system across a set of available devices. We present the state of the art about plastic 3D user interfaces. Moreover, we present well known methods in the field of 2D user interfaces that could become relevant for 3D user interfaces. With this survey, we show that current solutions do not meet all plasticity requirements. That is why we propose an action plan to meet these requirements.

Recent cultural heritage applications have been based on rich-content virtual environment (VE), in which virtual humans can communicate with visitors and other agents using natural language (NL). The conceptualisation of these dialogues are dependent on the contents of the application. Hence, we propose to use the semantic modelling of the VE and the activities of agents for the conceptualisation of the dialogue. Meta level semantic information are used as arguments in NLU/NLG rules. The advantage of this approach is that the dialogue rules are independent from the contents of the application and have clear semantics. We applied these principles to develop Brest’Coz, an interactive virtual tour for the learning of shipbuilding techniques used in France in early 18 th century.

In this article we introduce AReViRoad, a virtual reality tool: a traffic road simulator that enables one to determine the impact of the road network on traffic fluidity. The traffic generation is based on a multi-agent system in which each vehicle (an entity) is a software agent with its own behavior (autonomous). This solution offers a credible traffic road that will be used for testing a road network. With a set of given tools one can create one's own road network. Thereafter, one can configure one's own simulation (number of vehicles, tested road network, flow of car generators) and then launch, observe and analyse it with dedicated tools, such as a 3D view, flow meter and timer.

When visiting an aquarium, people may be disturbed or, at least, disappointed by the amount and diversity of available information. Moreover, one can find it very difficult to match the information of notices on the wall to the reality of the fishes. Therefore, we propose a virtual guide, an autonomous teaching assistant embodied in the real world using augmented reality techniques, for helping people in their visit of aquariums. This virtual guide will interact with the real world using multiple modalities (e.g. speech, facial expression, ...). Thus, it should be aware of the aquarium’s state and content, and use perceived information and prior knowledge to inform the visitor in a structured fashion. Due to the high mobility and unpredictable behaviour of the fishes, our guide requires an adequate perception system. This camera-based system has to keep track of the fishes and their behavior. It is based on the focalisation of visual attention that allows to select interesting information in the field of view. This is achieved by extracting a number of focuses of attention (FOA) using a saliency map and a multi-level memory system, which is filled (or updated) with the extracted information. It allows our system to detect and track targets in the aquarium. This article describes how we use the saliency map and memory system, along with their interactions, to set up the first part of our perception system.

Nowadays, traffic road simulators are often dedicated to learn technical gestures in connection with driving. Even if sometimes used to study driver behavior or reaction to a given situation, they don't take into consideration the social dimension of driving. In this way, we propose a traffic road simulator in which learners evolve under constrains defined by a teacher: the aim is to made person learn secure behavior on road. To do so, we axis our research on pedagogical aspect instead of physical simulation aspect. Consequently, we try to create virtual drivers which in interaction generate a credible traffic road from a learner point of view. In this article, we introduce the simulator and the pedagogical choices it implies and also the manner the traffic road is generated

In this paper we propose a new metaphor of information retrieving, usable in heritage management and publishing. Based on the net, the user is able to participate in virtual guided tours, sessions of conferences-like. A human expert will be the guide for all the connected users. He will use different media (sound/video) to communicate; the members of the guided group will communicate through chat sessions. Each virtual tourist will be autonomous in its 3D world movements but he will receive audio/video information or other multimedia documents or 3D objects, eventually autonomous entities placed in its 3D virtual universe, from its guide. The guide is able to suggest to its group of tourists some interesting viewpoints during the tour. More, he is able to augment the database, particularly the associated behaviours to the entities. It is enough to analyse the entities in a scene and to attach them some new behaviours. For example, he can place in the environment some virtual guides, and the users will interact with them. These virtual guides recognise some keywords or intentions; i.e. if a tourist spends some time near a specific place, the virtual guide will initiate a dialog upon the place's history. The user is able to cancel the dialog with a virtual guide and return to its group. The application is based on the AReViJava (Atelier de Realite Virtuelle) platform, developed in our laboratory.

In this paper we propose a new metaphor of information retrieving, usable in foundation heritage management and publishing. Based on the net, the user is able to participate in virtual guided tours, sessions of conference-like. A human expert will be the guide for all the connected users. He will use different media (sound/video) to communicate; the members of the guided group will communicate between them through chat sessions. Each virtual tourist will be autonomous in its 3D world movements but he will receive audio/video information or other multimedia documents or 3D objects, eventually autonomous entities placed in its 3D virtual universe, from its guide. The guide is able to suggest to its group of tourists some interesting viewpoints during the tour. More, he is able to augment the database, particularly the associated behaviours of the entities. It is enough to analyse the entities in a scene and to attach them some new behaviours. For example, he can place in the environment some virtual guides, and the users will interact with them. These virtual guides recognise some keywords or intentions; i.e. if a tourist spends some time near a specific place, the virtual guide will initiate a dialog upon the place's history. The user is able to cancel the dialog with a virtual guide and return to its group. The application is based on the ARéViJava (Atelier de Réalite Virtuelle) platform, developed in our laboratory.