Showing papers presented at "Virtual Environments, Human-Computer Interfaces and Measurement Systems in 2006"

A Novel 3D Graphical Password Schema

Abstract: In this paper, we propose and evaluate our contribution which is a new scheme of authentication. This scheme is based on a virtual three-dimensional environment. Users navigate through the virtual environment and interact with items inside the virtual three-dimensional environment. The combination of all interactions, actions and inputs towards the items and towards the virtual three-dimensional environment constructs the user's 3D password. The 3D password combines most existing authentication schemes such as textual passwords, graphical passwords, and biometrics into one virtual three-dimensional environment. The 3D password's main application is the protection of critical resources and systems.

A Scalable Hierarchical Architecture for Large Scale Multi-User Virtual Environments

Abstract: In this paper, we introduce a communication infrastructure based on using a hierarchical client-server model for facing the problem of Large Scale Collaborative Virtual Environments. Basically, we use a hierarchy of servers and, when the capacity of a server is reached, a new server is created as a son of the first one. The load is then distributed among the servers. We discuss and present the aspects of the proposed model and we also present efficient manners of solving problems inherent to client-server model. We specifically discuss techniques for grouping users, the allocation of users among servers, and definition of mixing and filtering operations. This paper also addressed the "shot in the crowd" problem, with a poposal of a solution.

Using Haptic Interfaces for User Verification in Virtual Environments

Abstract: Haptics can characterize the complex sense of touch and kinesthetic stimuli through its technology of force or tactile feedback devices. Such technology is developing fast enough to become soon another human-machine interaction similar to computer keyboard or mice. However, currently commercial haptics interfaces are expensive and are typically applied to research projects or expensive systems. Fortunately the trend of the market is forcing haptic developers to release products that can be affordable in a similar fashion as some specialized computer peripherals. Haptics aim is to allow a user to touch, feel, manipulate, create, and/or alter simulated three-dimensional objects in a virtual environment. Most of the applications are dedicated to train physical skills such as medical procedure by using desktop haptic units. These human skills can be captured to model a particular human-behavioural pattern that can be used to build a biometric recognition system. The precision of such systems is reliant on the choice of biometric identifiers. For accurate identity recognition, identifiers must be chosen so that they are unique for each individual. Conventional choices of biometric identifiers include writing style, hand geometry, as well as iris, facial, and fingerprint features. In this paper, we are interested in identity recognition based on humans' manipulation of haptic devices such as PHANToMtrade. The purpose of our analysis is to evaluate the information content of this data source. Hence, we assess the uniqueness of each biometric identifier. Our analysis shows that the haptic data content of identifiers is more suitable in a verification mode rather than in identification mode

The Implementation of an Automatic Measurement Station for the Determination of the Calibration Intervals for a DMM

Abstract: In the present work the authors present a procedure for the determination of the optimal calibration intervals of a measurement instrument according to the reference Standard. Generally speaking, the goal of a calibration process is to reduce out-of-tolerance occurrences to an acceptable level with respect to the desired quality target. The approach is based on the monitoring of the capability of an instrument in making measurements in conformity with the accuracy declared in the datasheet provided by the manufacturer. Periodic actions are required for the metrological confirmation, effected in a laboratory of tests, using for this purpose a reference instrument. In this paper is presented the implementation of an automatic station of measurement which performs an original procedure able to forecast the time to wait for the next calibration process.

An Open-source Software Architecture for Immersive Medical Imaging

Abstract: This paper presents an open-source software architecture for immersive medical imaging applications. In particular, the software system integrates open-source and cross-platform libraries for medical applications (VTK, ITK) with 3D graphic and virtual reality libraries (OpenSceneGraph, Chromium, VR Juggler) in order to efficiently support both operators and researchers in the medical field. In addition to this, the software system has been enhanced by pervasive computing characteristics like context-awareness and transparent access that enable mobile users to interact with the virtual environment, in a spontaneous and transparent way, with their own mobile devices.

Adaptive Quality Meshing for "on-the-fly" Volumetric Mesh Manipulations within Virtual Environments

Abstract: This paper presents a new approach for interactive 3D (volume) mesh manipulations based on `on-the-fly' quality measures in order to keep the consistency of the mesh. Within pure engineering tasks, such as the analysis of physical behaviour, virtual environments only established as post processing unit, in which simulation results can be interactively displayed and visualized to get more in depth information about the simulation mock up. However, most of the simulations are done off-line which do not allow for interactive 'what-if' analysis in view of a change of the primary design domain. As design changes of the underlying CAx/FE models usually imply many manual interferences, repair and efforts (re-meshing tasks, grid repair, etc.) in order to guarantee elements of high quality during re-meshing or mesh refinement tasks, an evaluation within virtual environments is not suitable with current techniques. Thus this paper aims at introducing our approach in order to change 3D volumetric meshes on the fly and keep the consistency of the newly generated mesh in view of engineering analysis.

A Dynamic Instrumentation Framework for Remote Operation of PC-Connected Devices

Abstract: The authors present a dynamic instrumentation framework for remote operation of PC-connected devices. The framework is dynamic in a way such that hardware information can be downloaded and added to the system at runtime. The hardware information consists of high-level hardware drivers and the graphical user interface (GUI) components to communicate with them. The solution makes it easy to maintain the instrumentation system, and the same system may be used to operate all PC-connected devices. The system is well suited for Internet-enabled calibration.

Interperception on Shared Virtual Environments

Abstract: In this work we introduces the concept of interdimensional virtual environments and proposes to it creation an architecture based on the client-server model. Our architecture allows the users with different resources sharing the same environment in a transparent way, same that users are connected by a different graphical interfaces. This interdimensionality provides by the system is possible thanks to the use of a component in the serving side that if put in charge to carry through, when necessary, the transformation of the messages of a dimension for another one, removing or adding indispensable information to the different customers of the system

An Adaptive Visual Gesture Based Interface for Human Machine Interaction in Intelligent Workspaces

Abstract: This paper describes the implementation of an artificial neural network based adaptive hand positioning and gesture recognition system for multimodal interfaces in intelligent workspaces. The system is based on a stereo vision system and provides a series of mechanisms for an efficient segmentation of the arm-hand structure over the screen and its description in terms of moments that can be used by a neural network based structure in order to provide position and gesture classification results. These can be adapted to the user's desires through an interaction and feedback mechanism permitting a natural mutual learning process between the system and the human.

Tactile Retina for Slip Detection

Abstract: The interest in tactile sensors is increasing as their use in complex unstructured environments is demanded, like in telepresence, minimal invasive surgery, robotics etc. The array of pressure data provided by these devices can be treated with different image processing algorithms to extract the required information. However, as in the case of vision chips or artificial retinas, problems arise when the array size and the computation complexity increase. Having a look at the skin, the information collected by every mechanoreceptor is not sent to the brain for its processing, but some complex pre-processing is performed to fit the limited throughput of the nervous system. This is specially important for high bandwidth demanding tasks. Experimental works report that neural response of skin mechanoreceptors encodes the change in local shape from an offset level rather than the absolute force or pressure distributions. Something similar happens in the retina, which implements a spatio-temporal averaging. We propose the same strategy in tactile preprocessing, and we show preliminary results illustrated for the case of slip detection, which is certainly demanding in computing requirements.

Haptic Aided Soft-touch Multi-material Product Design

Abstract: In recent years, thermoplastic elastomers (TPE) based multi-material molded products have found wide spread uses in various industries and every-day life. Today's computer-aided design (CAD) tools are very cumbersome in designing multi-material parts. This paper proposes a top-down design methodology to facilitate the design of multi-material products. Haptic technology is employed to enhance efficiency and intuitiveness of the designing process. Further more, some product properties such as stiffness can be readily evaluated in a haptic system. The proposed methodology is illustrated through a case study: the design of a toothbrush. IEEE Abstract

Enhancing Remote Walkthrough for E-learning Environments on Mobile Devices over Heterogeneous Networks

Abstract: With the growth of the Internet and availability of high bandwidth connections to domestic users, it became possible to deploy remote navigation within virtual environments over the Internet. For instance, virtual museum walkthrough, virtual mall, gaming, training, monitoring, and e-learning, just to name a few. We have also seen a new trend towards wireless networks and the use of mobile devices with wireless communication capabilities. Specially, e-learning environments can benefit from remote exploration of virtual environments over wireless networks in order to provide users with rich 3D content such as virtual laboratories and remote visits where users can interact with the 3D e-learning system using mobile devices such as PDAs, cellphones, or laptops. However, the characteristics of wireless channels pose significant problems to real-time interactive multimedia applications. Wireless bandwidth is always changing and the communication channel is highly susceptible to error. In this paper, we focus on the design of a remote walkthrough within realistic virtual environments over heterogeneous networks for mobile devices. We propose a real-time system that deals with the acquisition or remote geometry rendering, compression, packetization and transmission of images, which serve as input to an image-based rendering technique for fast creation of new views on the mobile client device. The objective is to contribute with a solution for remote walkthrough over wireless networks, while guaranteeing a good image quality and navigation at acceptable frame rates on thin client devices. Simulation experiments show that our design has low frame rate fluctuation, which is important in order to guarantee stable image quality

High-Precision Geometric Modeling of 3D Artifacts for Virtual Restoration

Abstract: This paper proposes a practical, topologically robust and ranging error resistive shape modeling procedure that approximates real physical 3D objects, such as archeological or cultural heritage artifacts, with the matrix-formatted organized meshing, enabling high-density scanning for high-resolution modeling and the successive 3D shape manipulation for restoration and modification. A face array listing (topology), which defines the vertex (mesh point) connectivity and the shape of the mesh, is pre-assigned to meet the desired scanning. Stable meshing, and hence, an accurate approximation, free from the shape ambiguity unavoidable in the widely used "retrieving topology from geometry" modeling procedures based on, for example, the Delaunay tessellations, is then accomplished. This proposal is practicable for all kinds of objects, automating the current manual, time-consuming reconstruction procedure, reducing rework requirement modeling and produce a versatile successive 3D shape manipulation.

Emotions and Interactive Agents

Abstract: Research regarding the manners in which the efficiency of human-computer interactions can be improved has increased over the last decade. Avatars, as animated software agents, represented a new paradigm for this field. In this paper we present a computer model of emotions that can be easily integrated in an avatar-based interaction context. Enhanced with the emotion model the avatars manifest an expressive behavior, ultimately influenced by their personality definitions. Interaction is facilitated by the emotional feedback user receives through the full body behavior of the avatar determined on its overall emotional state.

HumanPT: Architecture for Low Cost Robotic Applications

Abstract: In this paper an architecture for low cost robotic applications as well as its implementation in a commercial robot is presented. HumanPT architecture differs than other architectures because it is implemented on existing robotic systems (robot + robotic controller) and exploits the minimum communication facilities for real-time control that these systems provide. It is based on well-known communication methods like serial communication (USB, RS232, IEEE-1394) and windows sockets (server-client model) and permits an important number of different type of components like actuators, sensors and particularly vision systems to be connected in a robotic system. The operating system (OS) used is Microsoft Windows, the most widely spread OS. The proposed architecture exploits features of this OS that is not a real-time one, to ensure - in case that the robotic system provide such a facility-control and real time communication with the robotic system controller and to integrate by means of sensors and actuators an important number of robotic tasks and procedures. The proposed architecture provides the possibility in small enterprises to be automated enhancing in this way their production.

User Interface Design for VCMMs: an Approach to Increase Fidelity and Usability

Abstract: In recent years the declaration of uncertainties according to the ISO GUM (1995) has pushed the development of the so called Virtual Coordinate Measuring Machines - VCMMs as a software tool to generate uncertainty estimates for industrial applications. That is, a tool to calculate measurement uncertainty estimates based on real metrology information to be used in the context of quality systems. Recent tests on commercial VCMMs have shown that the fidelity of the simulation process to the real world is as important as the numerical correctness of uncertainty calculations. In this paper a VCMM interface design is proposed, focusing on techniques to increase the software fidelity and usability in industrial metrology applications. Results show that the quality of the simulation can be improved by proper user guidance as much as the software usability by the application of basic principles of software prototyping using the MVC model

Computer-Assisted Acquisition and Statistical Evaluation of Multifocal Visual Evoked Potentials

Abstract: The subject of this paper concerns the electro-physiological examination of the visual organ, the acquisition and statistical evaluation of the multifocal visual evoked potentials (M-VEP), in particular. The results presented are related to the real multifocal VEP waveforms, obtained during the examination of numerous patients in clinical conditions. The statistical evaluation of the results obtained during the examination of numerous healthy eyes enables the determination of electrical potential tolerance intervals and latency in the scope of the entire visual path of a healthy eye. Due to the lack of standardized values of the M-VEP test, the intervals may represent reference data in the valuation of various visual tract diseases. The data included therein, upon being exported to Microsoft Excel, enable the calculation of the average and standard deviation, and the tolerance intervals based on them.

Modeling of Virtually Manufactured Components with a Multiphase Perfect Material

Abstract: A component, which has an optimized combination of different materials (including homogeneous materials and different types of heterogeneous materials) in its different portions for a specific application, is considered as the component made of a multiphase perfect material. To manufacture such components, a hybrid layered manufacturing technology was proposed and a corresponding virtual manufacturing system has been created for its further research. The component made by a virtual manufacturing system is not a physical one but is a virtual one, i.e. a set of geometric and material information of the virtually manufactured component which should be recorded into a model in a specified data format in the course of virtual manufacturing. Such a model can be used to measure or evaluate the errors of the virtual manufacturing for its further optimization. This paper develops a modeling method and a corresponding system for the components virtually manufactured.

A Multimedia Framework for Collaborative Interaction of People and Robots Through the Web

Abstract: We propose a multimedia framework built on a flexible architecture designed for collaborative interaction of people and robots through the Web. Users can communicate to each other exchanging text, audio and video messages. Besides, it provides a flexible interface for people to interact with robots, for robots with people, and among robots themselves, for example, allowing a robot to communicate to another one. One or several users can communicate with one or more robots and also receive information from them. Robots can be remotely controlled through the use of keyboard, joysticks, data glove, and voice commands. A user can perceive other users through a virtual environment and receive the video from an environment, in which the robot is.

Designing Middleware System for Media Contents

Abstract: This paper attempts to consider future networks especially ad-hoc and wearable ones for media contents and game development. The study examined the consideration and the implementation of multi-agent system to support commercial or open source software for sound generating and computer graphics in personal area network (PAN). The multi-agent system maintains context information of sensors and users, and provides the event for contents application. In order to consider sensor network and global network, the ad-hoc network and peer-to-peer network are expected to use for organizing PAN. To implement the service on PAN, the widget integration framework (WIF), ontology and UML based context modeling approaches are considered and reported. (Balakrishman, et al.) On the other hand, we consider the Web service and possibility of future media contents in PAN. The research on wireless communication expects that next generation network consists of information appliances, sensors and wireless devices in PAN. Wearable computing has been researched for taking location and body information from small computers, and the efficient design of mobile HCI is emerging. Many papers report these technologies will be used for media art contents and game development. The digital contents will use these sensor s and mobile device in PAN. When the players join the game space with wearable computer in PAN, the mobile agent establishes the self-organized network in heterogeneous devices. In this paper, we consider the novel framework for media contents by hybrid ambient network

Virtual Hands for Risk Prevention Integration in Human-Computer Interactions

Abstract: The development of Virtual Reality offers new possibilities to better simulate and understand the human/system interactions. The current challenge is to take into account the Human Being in order to generalize the use of ergonomics in the design stage. We propose to improve the simulation of the interactions between man and machine by estimating the risk level of the working situation. After reviewing the previous work, we present our virtual physically-based hands which are coupled with a virtual press-brake by using a motion capture system. Thus, the operator can interact in real-time with the virtual environment. By integrating a dynamic risk index, we can also estimate the degree of hazard of the current working situation.

Algorithm for Efficiently Organizing and Searching Learning Objects in 3D Virtual Environments

Abstract: Reusable learning objects (RLO) are used in different contexts and are accompanied by their associated metadata for searching, managing, etc. This paper presents an application framework for metadata sharing, searching and visualizing techniques in a peer-to-peer network. The framework considers the semantic meaning of the query and applies context based peer address mapping to search metadata. We have also presented an algorithm for grouping metadata. By using a car metaphor, the grouped information is visualized in a 3d virtual environment for intuitive navigation and browsing that intends to show the context and relationship among the displayed results.

pH Neutralization Through Internet

Abstract: This project uses an IDAC-1 board to sample and control the pH level in a tank. The whole control is performed through the Internet. The experimental arrangement is placed on the task location and the controlling computer is located in a different one. Internet is the transport media. The protocol used in this project is UDP/IP. The pH level is measured by a pH meter and its output is sampled by an A/D converter integrated on the IDAC-1. To change the pH level ON-OFF valves control the free flow of light solutions acid and alkaline. The controlling computer through the Internet acting as client asks for the pH level, the IDAC-1 responds as server with the 10-bit resolution sampling pH meter. If pH is away from the set point the corresponding valve opens, neutralizing this way the solution. The whole procedure is logged in a file on the controlling computer. This application can give the ability to the Internet user to monitor and control the pH of a solution anywhere in the Word Wide Web (www).

Intelligent Virtual Interface for Improving Performance in HPC Centers by Modelling Users and their Satisfaction

Abstract: This paper deals with the implementation of a new approach that aims to improve the performance of High Performance Computing (HPC) centers through an agent based virtual interface that models the user behaviour and satisfaction. This interface translates user requests and satisfaction criteria into what is really necessary and, thus, permits the optimization of the HPC center's scheduler taking into account predicted user satisfaction together with the objectives of the management in terms of resource usage and cost. The system is based on an evolutionary profiling agent based architecture where the different agents are evolved in real time to adapt to the different users. These agents cooperate with the scheduling mechanism providing resource usage estimations for the different tasks, as well as predicting the effect of possible strategies on user satisfaction. Some experiments are presented where this system interacts with a real Job Management System (SGE) and we show that modelling the user and taking user satisfaction into account helps to improve system performance.

Design and Implementation of Monitoring Software Modules for Optical Protection Systems

Abstract: Because the optical network technique develops continuously, the nature of the test equipment used in the network will be more and more important, the remote monitor system is gaining importance for the operation of optical protection systems provide management and control of optical networks. In addition to the hardware module, the monitoring software module needed to be redesigned for automatically monitoring a group of optical modules of the hierarchy type. Our design provides a better function for the old product which can only monitor single type optical device, can't be reused, integrated and maintainable. Our design uses the network management (SNMP) interface which carries out remote supervision and use the RS232 interfaces to carry on local supervision. In addition, our design provides convenient in-time interface with the operational database functions, such as automatically the database data backup, security checking for data access and the hierarchical management scheme. Hence, our design can supervise and monitor a huge optical network system with 2500 objects, which will be continuously tested and the state of the operation situation recorded.

Elastic Properties Exploration of In Vitro Cultured Microscopic Cells based on Haptic Sensing

Abstract: This paper deals with the design of a micro-force sensing device for biomechanical characterization of biological samples. This device combines (SPM) techniques and advanced robotics approaches and allows to carry out in vitro prolonged observations as well as biomechanical characterization experiments. Elastic properties of biological samples are reflected to the macroscale during the mechanical characterization process by means of a haptic sensing device. Non-linear elasticity theory formalism is used in order to achieve realistic elastic rendering. Mechanical characterization experiments are conducted on human tumoral Epithilial Hella cells in order to demonstrate the efficiency and viability of the proposed system.

Dynamic Simulation for Grid Computing Systems

Abstract: Grid computing systems are emerging as a consequence of the growing internet connectivity in combination with the need of shared resources to deploy large-scale scientific applications. In such a context, heterogeneity, decentralization, location, access and availability of resources need to be dealt with suitable simulation tools. In particular, overloading conditions may be critical and difficult to analyse when the grid is requested to guarantee affordable high performances. To deal with such a challenging task, a virtual simulation environment provided with a suitable graphical interface has been developed as the means for comparative analysis with real test bed activities.

Innovae Emotional Trainer: an Interactive System to Measure People's Acting Skills

Abstract: We describe the facial emotion reading and teaching system we have developed as an entertainment and educational tool to be placed in science museums. We describe the computational elements in detail as well as a recognition experiment and the results obtained.

A self-calibrating Virtual Instrument for THD Measurements

Abstract: In the present work the authors present the realization of a virtual instrument implementing a self-calibrating THD meter. The instrument is able to draw an electrical signal provided from a phase of the electrical distribution network, and to evaluate its total harmonic distortion (THD). Actually the instrument calibration process is developed in two times: at first a "black box calibration" is executed (it concerns the system consisting, for a quite general purpose digital device, in: voltage/current transducers + ADCs + Data Processing including the FFT calculation and the determination of the amplitude of the fundamental frequency component); the process is performed by using a reference instrument every time it is consider necessary (that's to say every time the period of use might be cause of not too good performances of the instrument). The results, opportunely stored as a matrix of partial accuracies in the non-volatile memory of the data processing unit, allow the determination of the uncertainty related to the THD calculation through an algorithm in conformance with The ISO Guide on the expression of the uncertainty of indirect measurements (this last represents the second step of the calibration procedure). For this reason the whole calibration act is defined by the authors of the present paper as a "grey box calibration". During the measurement, in fact, the instrument gets ready to the self-calibration by using a fuzzy representation of the harmonic components, so to achieve the expression of the cited power quality index in terms of an interval defined for a specified confidence level selected by the user. The proposed methodology proves to be of fast and simple application not only for virtual instruments, but also for stand-alone measurers based on DSP or FPGA technologies

A Localization Method Based on Infrared Detectors for Surveillance Areas

Abstract: This article presents a localization method based on a net of infrared sensor. Each of the detectors provide o binary signal without any possibility to establish localization. But observing the reaction of the sensors when parameters are modified and using a net of sensors we establish a localization method. This method is based on analyzing the simultaneous activations and the development in time of the output signals of each detector. Also, using this fuzzy method, it can be obtain not only the localization of the intrusion but also it can be estimated the heating surface of the object which produced the intrusion.