Ronan Querrec

Semantic modeling of Virtual Environments using MASCARET

Many Virtual Reality (VR) applications, such as Virtual Learning Environments or Interactive Virtual Tours, are based on a rich semantic description of the environment and tasks that users have to perform. These applications are built upon Virtual Environments (VEs) in which artificial agents act autonomously while interacting in realtime with users. Semantic modelling of a VR environment makes it possible the knowledge-driven access from the description of VEs that simplifies the development of VR applications. It eases the development of these types of applications. Semantic modelling should provide a consistent representation of the following aspects: 1) The simulated world, its structure and the behavior of its entities, 2) Interactions and tasks, that users and agents can perform in the environment, 3) Knowledge items, that autonomous agents can use for decision-making or for communication with users. This paper presents MASCARET, a model-based approach, for the design of semantic VR environments. This approach is based on the Unified Modeling Language (UML). In this approach, UML is used to provide a knowledge-driven access to the semantic contents of the VE and not for code generation, as in classical software development process. Interests of a UML-based approach are that its metamodel covers different views of the semantic modelling: ontology, structure, behaviors, interactions, activities. It is also an extensible language that can be specialized to provide formal operational semantics. We also present how MASCARET can be used to develop content-rich interactive applications that can be deployed over various VR platforms. Finally, we discuss the benefits of such a metamodel-based approach and show how the multi-layer semantic model can be used in different VR applications, in which adaptive behaviors of artificial agents acting within complex environments have to be simulated.

Virtual Storytelling for Training: An Application to Fire Fighting in Industrial Environment

The goal of this project is to build a virtual reality platform to educate fire fighters officers. Virtual reality allows to immerse users (teacher and learners) in a universe where the physical environment and human actors behavior are simulated. We propose an architecture where everything is an agent: reactive agents (natural phenomena), cognitive agents (firemen) and avatars (users). The two last types of agents coordinate their actions: they play a role in an organization to execute pre-established missions in team.

MASCARET: A Pedagogical Multi-Agent System for Virtual Environments for Training

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Mascaret: Pedagogical multi-agents system for virtual environment for training. Cédric Buche, Ronan Querrec, Pierre De Loor, Pierre Chevaillier

An expert system manipulating knowledge to help human learners into virtual environment

This research is situated within the context of the creation of human learning environments using virtual reality. We propose the integration of a generic and adaptable intelligent tutoring system (Pegase). The aim is to instruct the learner, and to assist the instructor. The multi-agent system emits a set of knowledge (actions carried out by the learner, knowledge of the field, etc.) used by an artificial intelligence to make pedagogical decisions. Our study focuses on the representation of knowledge about the environment, and on the adaptable pedagogical agent providing instructive assistance.

GASPAR : Aviation Management on an Aircraft Carrier Using Virtual Reality

To provide for its needs, the French Navy plans to build a second aircraft carrier. With this intention, the navy draws up a list of its functional requirements and delegates to DCNS the development of the technical specifications focusing on the fact that the ship fulfills those requirements. The principal difficulty lies in the specification of the aviation management on the aircraft carrier. In this paper, we describe GASPAR, a virtual-reality application developped in order to simulate different configurations of the future aircraft carrier and test their viability. We first introduce AR´EVI and MASCARET, the librairires upon which the application is built, then we present the application. Finally, we present some results that GASPAR has validated about the ship.

Ensuring semantic spatial constraints in virtual environments using UML/OCL

Spatial objects and relationships between them, compose a spatial model that is the backbone of virtual environments (VEs). However, due to the natural complexity of both spatial objects and spatial information, the modeling of such spatial relationships is still a difficult task. This paper presents a novel approach for representing semantic spatial relations in VEs using the Unified Modeling Language (UML) and the Object Constraint Language (OCL). Our approach first uses the UML class model as a conceptual model for VEs. We then propose a spatial extension of OCL named VRX-OCL as a high-level and flexible language to cover multidimensional, manifold, and reference frame-dependent spatial constraints. We mainly focus on two important classes of spatial relations, namely, topological and projective relations that allow nonmetric representation of space. The applicability of our approach is demonstrated in the Virtual Physics Laboratory, a VE for learning physics. Based on the constraints satisfaction, the system is able to visualize abstract spatial information and thus provides educational assistance to the learners.

MASCARET: creating virtual learning environments from system modelling

The design process for a Virtual Learning Environment (VLE) such as that put forward in the SIFORAS project (SImulation FOR training and ASsistance) means that system specifications can be differentiated from pedagogical specifications. System specifications can also be obtained directly from the specialists’ expertise; that is to say directly from Product Lifecycle Management (PLM) tools. To do this, the system model needs to be considered as a piece of VLE data. In this paper we present Mascaret, a meta-model which can be used to represent such system models. In order to ensure that the meta-model is capable of describing, representing and simulating such systems, MASCARET is based SysML1, a standard defined by Omg.

TIP-EXE: A Software Tool for Studying the Use and Understanding of Procedural Documents

Research problem: When dealing with procedural documents, individuals sometimes encounter comprehension problems due to poor information design. Researchers studying the use and understanding of procedural documents, as well as technical writers charged with the design of these documents, or usability specialists evaluating their quality, would all benefit from tools allowing them to collect real-time data concerning user behavior in user-centered studies. With this in mind, the generic software Technical Instructions Processing-Evaluations and eXperiments Editor (TIP-EXE) was designed to facilitate the carrying out of such studies. Research questions: Does document design, and specifically the matching or mismatching of the terms employed in a user manual and on the corresponding device, affect the cognitive processes involved in the comprehension of procedural instructions? Can we use a software tool like TIP-EXE to assess the impact of document design on the use and understanding of a procedural document? Literature review: A review of the methods employed to study either the use of procedural documents or their cognitive processing, and to evaluate the quality of these documents, revealed the lack of tools for collecting relevant data. Methodology: TIP-EXE software was used to set up and run a laboratory experiment designed to collect data concerning the effect of document design on the performance of a task. The experiment was conducted with 36 participants carrying out tasks involving the programming of a digital timer under one of three conditions: “matching instructions,” “mismatching instructions,” “mismatching instructions + picture”. Based on a click-and-read method for blurred text, TIP-EXE was used to collect data on the time the users spent reading the instructions, as well as the time spent handling the timer. Results and discussion: Results show that “matching instructions” (when the terms employed in the user manual match the terms on the device) enhance user performance. This instructional format results in less time spent consulting the instructions and handling the device, as well as fewer errors. This research shows that TIP-EXE software can be used to study the way in which operating instructions are read, and the time spent consulting specific information contained therein, thereby revealing the effects of document design on user behavior.

Agent Metamodel for Virtual Reality Applications

The various existing agent models do not cover all the possible uses we consider for virtual reality applications. In this paper, we present an agent metamodel (Behave) based on an environment metamodel (Veha). This metamodel allows defining agents and organizing teams of agents in a virtual environment. The use of this metamodel is illustrated by the Gaspar application which simulates activities on an aircraft carrier.

Wind turbines' landscape: using virtual reality for the assessment of multisensory perception in motion

Wind turbines (WT) are socially controversial because of their visual and acoustic impacts on landscape. Virtual reality (VR) is here proposed - thanks to immersion and interaction potentialities - as an immersive and multisensory approach in order to assess WT impacts. For that, a comparison between a real park and the same virtual one is needed to evaluate VR for landscape impacts restitution. The parks are evaluated using an urban path-based method (perception in motion): the real walking is simulated by a Wiimote in vitro. The results, while very similar to the in situ study show the limits of the lack of free motion.