Collaborative Virtual Environment Applications Research Articles

A Study on the Presence of Immersive User Interface in Collaborative Virtual Environments Application

This study proposes a collaboration-based interaction as a new method for providing an improved presence and a satisfying experience to various head-mounted display (HMD) users utilized in immersive virtual reality (IVR), and analyzes the experiences (improved presence, satisfying enjoyment, and social interaction) of applying collaboration to user interfaces. The key objective of the proposed interaction is to provide an environment where HMD users are able to collaborate with each other, based on their differentiated roles and behaviors. To this end, a collaboration-based interaction structured in three parts was designed, including a synchronization procedure and a communication interface that enable users to swiftly execute common goals with precision, based on immersive interactions that allow users to directly exchange information and provide feedback with their hands and feet. Moreover, experimental VR applications were built to systematically analyze the improved presence, enjoyment, and social interaction experienced by users through collaboration. Finally, by conducting a survey on the participants of the experiment, this study confirmed that the proposed interface indeed provided users with an improved presence and a satisfying experience, based on collaboration.

On consistency and security issues in collaborative virtual environment systems

This paper survey security issues in collaborative virtual environments (CVEs) systems. In CVE, multiple users work on different computers which are interconnected through different networks to interact in a shared virtual world. Due to the nature of the geographically disperse users and their connection via different networks, there are numerous security threats that denied fulfillments of most important CVE requirements which have been ignored (e.g. consistency). In this paper, we outlined the types of collaborative virtual environment applications that can be affected by security threats and attacks, it discussed some of the most important CVE systems security requirements, and then discussed the different types of security threats and attacks related to CVE systems security requirements. Finally, we describe the state of the art of CVE system security. Key words: Collaborative virtual environments (CVE), security requirement, threats, attack.

Networked Collaborative Design and Control for Collaborative Product Development Using Haptic Interface

AbstractThis paper presents a collaborative product development and prototyping by using distributed haptic interfaces along with deformable objects modeling. Collaborative Virtual Environment (CVE) is a promising technique for industrial product development and virtual prototyping. Network control problems such as network traffic and network delay in communication have greatly limited collaborative virtual environment applications. The problems become more difficult when high-update-rate haptic interfaces and computation intensive deformable objects modeling are integrated into CVEs for intuitive manipulation and enhanced realism. A hybrid network architecture is proposed to balance the computational burden of haptic rendering and deformable object simulation. Adaptive artificial time compensation is used to reduce the time discrepancy between the server and the client. Interpolation and extrapolation approaches are used to synchronize graphic and haptic data transmitted over the network. The proposed te...

Hybrid client–server architecture and control techniques for collaborative product development using haptic interfaces

In this paper, a collaborative product development and prototyping framework is proposed by using distributed haptic interfaces along with deformable objects modeling. Collaborative Virtual Environment (CVE) is a promising technique for industrial product development and virtual prototyping. Network control problems such as network traffic and network delay in communication have greatly limited collaborative virtual environment applications. The problems become more difficult when high-update-rate haptic interfaces and computation intensive deformable objects modeling are integrated into CVEs for intuitive manipulation and enhanced realism. A hybrid network architecture is proposed to balance the computational burden of haptic rendering and deformable object simulation. Adaptive artificial time compensation is used to reduce the time discrepancy between the server and the client. Interpolation and extrapolation approaches are used to synchronize graphic and haptic data transmitted over the network. The proposed techniques can be used for collaborative product development, virtual assembly, remote product simulation and other collaborative virtual environments where both haptic interfaces and deformable object models are involved.

Behaviour‐based multiplayer collaborative interaction management

AbstractA collaborative virtual environment (CVE) allows geographically dispersed users to interact with each other and objects in a common virtual environment via network connections. One of the successful applications of CVE is multiplayer on‐line role‐playing game. To support massive interactions among virtual entities in a large‐scale CVE and maintain consistent status of the interaction among users with the constraint of limited network bandwidth, an efficient collaborative interaction management method is required. In this paper, we propose a behaviour‐based interaction management framework for supporting multiplayer role‐playing CVE applications. It incorporates a two‐tiered architecture which includes high‐level role behaviour‐based interaction management and low‐level message routing. In the high level, interaction management is achieved by enabling interactions based on collaborative behaviour definitions. In the low level, message routing controls interactions according to the run‐time status of the interactive entities. Collaborative Behaviour Description Language is designed as a scripting interface for application developers to define collaborative behaviours of interactive entities and simulation logics/game rules in a CVE. We demonstrate and evaluate the performance of the proposed framework through a prototype system and simulations. Copyright © 2006 John Wiley & Sons, Ltd.

Making Networked Virtual Environments Work

Collaborative virtual environments (CVEs) are a promising technology enabling remote participants to share a common place through three-dimensional graphical scenes. Within the COVEN project (Normand, 1999), we have run prolonged series of Internet trials that have allowed us to gather valuable data to formulate usability guidelines and networking requirements. However, running such trials in a real setting and making sure that the application and networking infrastructures will be stable enough is still a challenge. In this paper, we describe some of our experiences, together with the technical choices that have permitted many hours of successful Internet trials. We also make a thorough analysis of different correlated logging data. This analysis allows us to propose and confirm a model of a CVE application's network behavior, together with a number of interesting results that disprove some common assumptions. Furthermore, we use the model and the logging data to highlight the benefits of IP multicasting and for predicting traffic behaviors and bandwidth use on top of different logical network topologies.

Predicting network traffic for collaborative virtual environments

We introduce a method for predicting the network traffic that will be generated by collaborative virtual environment applications with varying numbers of participants. Statistical analysis of event logs from user trials results in a user behaviour model. Controlled traffic measurements combined with an analysis of the application architecture and network topology results in a system behaviour model. These two models are combined to produce a network traffic model. We describe the application of this method to a business game application that has been developed as part of the COVEN project. Finally, we make some general observations concerning the network traffic generated by CVEs including its bursty nature and the potential use of techniques such as multicasting and statistical multiplexing to reduce network load.