Virtual Simulation Environment Research Articles

Dynamic Blackout Probability Monitoring System for Cruise Ship Power Plants

Stringent environmental regulations and efforts to improve the shipping operations sustainability have resulted in designing and employing more complex configurations for the ship power plants systems and the implementation of digitalised functionalities. Due to these systems complexity, critical situations arising from the components and subsystem failures, which may lead to accidents, require timely detection and mitigation. This study aims at enhancing the safety of ship complex systems and their operation by developing the concept of an integrated monitoring safety system that employs existing safety models and data fusion from shipboard sensors. Detailed Fault Trees that model the blackout top event, representing the sailing modes of a cruise ship and the operating modes of its plant, are employed. Shipboard sensors’ measurements acquired by the cruise ship alarm and monitoring system are integrated with these Fault Trees to account for the acquired shipboard information on the investigated power plant configuration and its components operating conditions, thus, facilitating the estimation of the blackout probability time variation as well as the dynamic criticality assessment of the power plant components. The proposed concept is verified by using a virtual simulation environment developed in Matlab/Simulink. This study supports the dynamic assessment of the ship power plants and therefore benefits the decision-making for enhancing the plant safety during operations.

Digital twin for the integration of the automatic transport and manufacturing processes

Simulation techniques for time calculation in industrial transport are not currently deterministic. This supposes a time uncertainty in production planning with economic implications. The digitization promoted by Industry 4.0 allows the automation of transport in manufacturing processes. In this way, the Automated Guided Vehicles (AGVs) performance can be simulated to obtain more accurate results. The definition of a virtual simulation environment through digital twins is an incipient area of research in this field. Digital twins achieve this purpose without intervening in the physical world thus minimising costs. In order to facilitate the use of digital twins, in this paper, we implement a web-based simulation service to improve the user experience. The user will be able to pose hypotheses and visualise the execution in real-time. The techniques implemented for the simulations are based on Robot Operating System (ROS) within the Gazebo environment, IIoT communications require the Node-network programming environment which is in charge of the hyperconnectivity and the creation of the user interface.

Applying virtual reality to teach the software development process to novice software engineers

Software development is a complicated process that requires experienced human resources to produce successful software products. Although this process needs experience from the individuals, it is hard to provide this experience without encountering real incidents during the software development process. To fill this gap, this study proposes a Virtual Reality Based Software Development Framework (VR-SODEF), which provides an interactive virtual reality experience for individuals learning about the tasks of software development starting from requirement analysis through software testing. In the VR-SODEF, the participant takes on the role of a novice software developer being recruited into a virtual software development organisation who should work alongside five virtual characters, played by artificial intelligence. This exclusive viewpoint draws participants from the 2D separation of the classical experience and virtually into the world of the software development itself. Participants experience the intense dramatic elements created for simulation and confront the challenges of virtual software practitioners in a somewhat uncompromising virtual simulation environment. To examine the efficiency of the VR-SODEF, it was tested on 32 computing students, with results indicating that virtual reality can be an effective educational medium, especially for skills that might traditionally be acquired through experience rather than traditional classroom-based teaching.

Performance evaluation of a state-of-the-art automotive radar and corresponding modeling approaches based on a large labeled dataset

Radar is a key sensor to achieve a reliable environment perception for advanced driver assistance system and automated driving (ADAS/AD) functions. Reducing the development efforts for ADAS functions and eventually enabling AD functions demands the extension of conventional physical test drives with simulations in virtual test environments. In such a virtual test environment, the physical radar unit is replaced by a virtual radar model. Driving datasets, such as the nuScenes dataset, containing large amounts of annotated sensor measurements, help understand sensor capabilities and play an important role in sensor modeling. This article includes a thorough analysis of the radar data available in the nuScenes dataset. Radar properties, such as detection thresholds, and detection probabilities depending on object, environment, and radar parameters, as well as object properties, such as reflection behavior depending on object type, are investigated quantitatively. The overall detection probability of the considered radar (Continental ARS-408-21) was found to be 27.81%. Four radar models on object level with different complexity levels and different parametrisation requirements are presented: a simple RCS-based radar model with an accuracy of 51%, a linear SVC model with an accuracy of 70%, a Random Forest model with an accuracy of 83%, and a Gradient Boost model with an accuracy of 86%. The feature importance analysis of the machine learning algorithms revealed that object class, object size, and object visibility are the most important parameters for the presented radar models. In contrast, daytime and weather conditions seem to have only minor influence on the modeling results.

A virtual geographic environment for dynamic simulation and analysis of tailings dam failure

ABSTRACT It is of great significance for disaster prevention and mitigation to carry out disaster simulations for dam failure accidents in advance, but at present, there are few professional systems for disaster simulations of tailings dams. In this paper, we focused on the construction of a virtual geographic environment (VGE) system that provides an effective tool for visualizing the dam-break process of a tailings pond. The dam-break numerical model of the tailings dam based on computational fluid dynamics (CFD) was integrated into the VGE system. The infrastructure of the VGE was supported by a 3-D geographic information system (GIS) with a user-friendly interface for the initiation, visualization, and analysis of the dynamic process of tailings dam failure. Key technologies, including the integration of numerical models, rendering of large-scale scenes, and optimizations of disaster simulation and visualization, were discussed in detail. In the prototype system, information on the run-out path, travel distance, etc. can be obtained to visually describe the flow motion released by two dam failure cases. The simulation results showed that the VGE can be used for the multidimensional, dynamic and interactive visualization of dam-break disasters, and can also be useful for assessing the risk associated with tailings dams.

APPLICATION OF SPEED AND SEPARATION MONITORING TECHNIQUE AT AUTOMATED ASSEMBLY PROCESS

The realization and implementation of a collaborative robotic system in the automotive industry has many advantages in productivity, product quality, and worker ergonomics, but worker safety aspects play a crucial role in these activities. This paper presents the results of ongoing research into developing an automated workplace for an assembly of industrial limit switches based on the cooperation between human and robotic systems. Operating speed and worker-robot separation monitoring methodology (SSM) was used as one of the available methods to reduce the risk of injury according to the technical specification ISO 15066 on collaborative method sharing space with humans. The virtual environment simulation aims to determine the SSM algorithm’s parameters to estimate the minimum protective distance between the robot and the operator. The cooperation between the human and the robot and the safety issues specified by the SSM system assumed operational safety and reduced the operator fatigue during the assembly process.

A study of real-time simulation of liver of virtual surgical robot based on biologically position-based dynamic model

Virtual surgery robot can accurately modeling of surgical instruments and human organs, and realistic simulation of various surgical phenomena such as deformation of organic tissues, surgery simulation system can provide operators with reusable virtual training and simulation environment. To meet the requirement of virtual surgery robot for the authenticity and real-time of soft tissue deformation and surgical simulation in liver surgery, a new method is proposed to simulate the deformation of soft tissue. This method combines the spring force, the external force of the system, and the constraint force produced by the constraint function of the position-based dynamics. Based on the position-based dynamics, an improved three-parameter mass-spring model is added. In the calculation of the elastic force, the nonlinearity and viscoelasticity of the soft tissue are introduced, and the joint force of the constraint projection process and the constraint force of the position-based dynamics is used to modify mass points movement. The method of position-based dynamics based on biological characteristics, not only considers the biomechanical properties of biological soft tissue as an organic polymer such as viscoelasticity, nonlinearity, and incompressibility but also retains the rapidity and stability of the position based dynamic method. Through the simulation data, the optimal side length of tetrahedral mesh in the improved three-parameter model is obtained, and the physical properties of the model are proved. The real-time simulation of the liver and other organs is completed by using the Geomagic touch force feedback device, which proves the practicability and effectiveness of this method.

Influence of virtual reality on student learning in undergraduate construction education

ABSTRACT Virtual Reality (VR) allows for an active learning environment that can enhance a student’s comprehension of material. This research explores the actual and perceived benefit of introducing a VR simulation into a materials and methods of construction course in undergraduate education. The study included the development and implementation of a virtual simulation environment to support learning in the materials and methods of construction course. Actual student performance was then compared between a control group, who did not use the simulation, and the intervention group, those who used the simulation. Other factors such as student self-efficacy, learning motivation, and technology acceptance for the intervention group were also examined. Findings suggest that students who utilized the simulation have a better understanding of the course material represented in the simulation compared to those that were only exposed to traditional course materials.

Exploration of the effects of task-related fatigue on eye-motion features and its value in improving driver fatigue-related technology

Mental fatigue has been lacked attention in developing eye-tracking fatigue detection system for drivers. However, it has great influence on eye movement which could account for the poor validity of current fatigue detectors only focusing on sleep-related fatigue. This work sought to investigate the influence of two types of task-related mental fatigue on eye movement by examining 8 saccade-based, 3 blink-based, and 1 pupil-based metrics. We propose that two types of task-related fatigue caused by cognitive overload and prolonged underload will induce different physiological responses to eye-motion features. Twenty participants completed a vigilance task before and after a 1-h driving with a secondary task in a virtual simulation environment, while forty participants, divided equally into two groups, finished the same task before and after a 1-h and 1.5-h monotonous driving. T-test was applied to analyse the eye-motion, subjective and vigilance data during vigilance task. We found that overload driving made drivers vigilance ability decrease. The eye metrics showed different changes in underload and overload scenario. The blink duration, the mean velocity of saccade and saccade duration increased after 1-h overload driving, while the pupil diameter decreased. However, none of those changes were observed in 1.5-h underload driving, but saccade duration had a significant increase. The fatigue response to heavy demands over short periods of driving is different from the lighter demands over long periods in terms of eye-motion metrics. Considering mental fatigue in designing an eye-tracking fatigue detection system could possibly improve its accuracy.

Inducing lateralized phosphenes over the occipital lobe using transcranial magnetic stimulation to navigate a virtual environment.

Electrical stimulation involving visual areas of the brain produces artificial light percepts called phosphenes. These visual percepts have been extensively investigated in previous studies involving intracortical microsimulation (ICMS) and serve as the basis for developing a visual prosthesis for the blind. Although advances have been achieved, many challenges still remain with implementing a functional ICMS for visual rehabilitation purposes. Transcranial magnetic stimulation (TMS) over the primary occipital lobe offers an alternative method to produce phosphenes non-invasively. A main challenge facing blind individuals involves navigation. Within the scientific community, methods to evaluate the ability of a visual prosthesis to facilitate in navigation has been neglected. In this study, we investigate the effectiveness of evoking lateralized phosphenes to navigate a computer simulated virtual environment. More importantly, we demonstrate how virtual environments along with the development of a visual prosthesis share a mutual relationship benefiting both patients and researchers. Using two TMS devices, a pair of 40mm figure-of-eight coils were placed over each occipital hemisphere resulting in lateralized phosphene perception. Participants were tasked with making a series of left and right turns using peripheral devices depending on the visual hemifield in which a phosphene is present. If a participant was able to accurately perceive all ten phosphenes, the simulated target is able to advance and fully exit the virtual environment. Our findings demonstrate that participants can interpret lateralized phosphenes while highlighting the integration of computer based virtual environments to evaluate the capability of a visual prosthesis during navigation.

RETRACTED ARTICLE: Embedded system virtual simulation platform and political teaching in MOOC network information environment

MOOC has completely open and free features. These features make it possible to use MOOC without any restrictions and restrictions. Moreover, this platform can be opened to many people on a large scale at the same time. The network is very smooth, and it is convenient for many people to learn through the network. Take online learning. In the innovative education model of Internet + education, the MOOC learning platform is the best resource using the Internet. Adding embedded technology to the classroom learning platform is a very smart approach. At the same time, this choice will also provide a better service path for students who conduct academic research and academic writing, so that students and teachers can embed the classroom learning platform makes targeted choices so as to make your choices more in line with your requirements and find more suitable learning resources. This choice is generally liked and accepted by teachers and students in practice. The embedded virtual simulation environment has strong scalability. After the embedded virtual simulation platform is embedded in the MOOC learning platform, the advantages of virtual simulation and MOOC can be complemented, thereby providing a faster, more stable, more high-quality and efficient learning system platform.

Virtual Scenario Simulation and Modeling Framework in Autonomous Driving Simulators

Recently, virtual environment-based techniques to train sensor-based autonomous driving models have been widely employed due to their efficiency. However, a simulated virtual environment is required to be highly similar to its real-world counterpart to ensure the applicability of such models to actual autonomous vehicles. Though advances in hardware and three-dimensional graphics engine technology have enabled the creation of realistic virtual driving environments, the myriad of scenarios occurring in the real world can only be simulated up to a limited extent. In this study, a scenario simulation and modeling framework that simulates the behavior of objects that may be encountered while driving is proposed to address this problem. This framework maximizes the number of scenarios, their types, and the driving experience in a virtual environment. Furthermore, a simulator was implemented and employed to evaluate the performance of the proposed framework.

Virtual Reality Scenario Design for Distance Learning With Google Poly

Introduction:The COVID-19 pandemic caused a rush to produce online and distance learning activities throughout higher education. Many programs were unprepared for a shift in simulation scenario delivery that allowed immersive clinical training. Virtual reality software and hardware have barriers of cost and knowledge implementation.Objectives:This paper will introduce the techniques to allow healthcare simulation technology specialists to create immersive web-based simulation scenarios using existing equipment to support online and distance learning objectives using the Google Poly platform.Methods:Equirectangular images were shot using a 360-degree video camera or stitched using a smartphone camera. These images of a staged immersive simulation room were loaded into the Google Poly online platform. Curriculum specific design elements were added based on a prior in-person scenario outline. Multiple scenes can be combined into a single virtual scenario that allows a learner to progress through multiple patient encounters or phases of a single patient encounter.Results:A simple web browser interface allows asynchronous navigation of this customized virtual simulation environment using existing PCs or smart phone equipment. This same virtual environment can also be experienced using VR headsets of VR viewers such as Google Cardboard. The Google Poly scene creation platform allows the addition of ‘points of interest’ that allows learners to view specific areas of the scene to see images that add additional detail or even play back media such as heart and lung sounds.Conclusion:Existing free open-source tools such as Google Poly can allow simulation centers to create immersive clinical simulation scenarios that are sharable as a distance learning solution to augment clinical experience.

Functional brain connectivity related to surgical skill dexterity in physical and virtual simulation environments.

.Significance: Surgical simulators, both virtual and physical, are increasingly used as training tools for teaching and assessing surgical technical skills. However, the metrics used for assessment in these simulation environments are often subjective and inconsistent.Aim: We propose functional activation metrics, derived from brain imaging measurements, to objectively assess the correspondence between brain activation with surgical motor skills for subjects with varying degrees of surgical skill.Approach: Cortical activation based on changes in the oxygenated hemoglobin (HbO) of 36 subjects was measured using functional near-infrared spectroscopy at the prefrontal cortex (PFC), primary motor cortex, and supplementary motor area (SMA) due to their association with motor skill learning. Inter-regional functional connectivity metrics, namely, wavelet coherence (WCO) and wavelet phase coherence were derived from HbO changes to correlate brain activity to surgical motor skill levels objectively.Results: One-way multivariate analysis of variance found a statistically significant difference in the inter-regional WCO metrics for physical simulator based on Wilk’s Λ for expert versus novice, , . Partial eta squared effect size for the inter-regional WCO metrics was found to be highest between the central prefrontal cortex (CPFC) and SMA, CPFC-SMA (). Two-tailed Mann–Whitney U tests with a 95% confidence interval showed baseline equivalence and a statistically significant () difference in the CPFC-SMA WPCO metrics for the physical simulator training group () versus the untrained control group () following training for 10 consecutive days in addition to the pretest and posttest days.Conclusion: We show that brain functional connectivity WCO metric corresponds to surgical motor skills in the laparoscopic physical simulators. Functional connectivity between the CPFC and the SMA is lower for subjects that exhibit expert surgical motor skills than untrained subjects in laparoscopic physical simulators.

Development of a Virtual Environment Co-Simulation Platform for Evaluating Dynamic Characteristics of Self-Balancing Personal Mobility

As with the expansion of self-balancing personal mobility (SBPM) market, increasing number of accidents are being reported recent years while relevant safety regulations are not established yet. Hence development of technology associated with the evaluation of safety and stability of SBPM is essential. In evaluating the safety, SBPM cannot be tested physically for all different conditions due to many reasons. Therefore, we developed a virtual environment simulation platform capable of reproducing the dynamic behavior of SBPM for various driving conditions accurately thereby replacing the actual tests and being used as a platform for the evaluation of safety/stability of SBPM. To construct the co-simulation platform, model of SBPM was built in RecurDyn using the actual measurement data of a commercial SBPM product, and two internal controllers (self-balancing controller, and yaw-rate command controller) that play key roles in realizing the dynamic characteristics of SBPM were experimentally identified and were implemented into the RecurDyn model using MATLAB/Simulink. Validity of the virtual environment co-simulation platform was verified through the comparison with the experimental data.

RadVR: A 6DOF Virtual Reality Daylighting Analysis Tool

This work introduces RadVR, a virtual reality tool for daylighting analysis that simultaneously combines qualitative assessments through immersive real-time renderings with quantitative physically correct daylighting simulations in a 6DOF virtual environment. By taking a 3D building model with material properties as input, RadVR allows users to (1) perform physically-based daylighting simulations via Radiance, (2) study sunlight in different hours-of-the-year, (3) interact with a 9-point-in-time matrix for the most representative times of the year, and (4) visualize, compare, and analyze daylighting simulation results. With an end-to-end workflow, RadVR integrates with 3D modeling software that is commonly used by building designers. Additionally, by conducting user experiments we compare the proposed system with DIVA for Rhino, a Radiance-based tool that uses conventional 2D-displays. The results show that RadVR can provide promising assistance in spatial understanding tasks, navigation, and sun position analysis in virtual reality.

Toward Autonomous UAV Localization via Aerial Image Registration

Absolute localization of a flying UAV on its own in a global-navigation-satellite-system (GNSS)-denied environment is always a challenge. In this paper, we present a landmark-based approach where a UAV is automatically locked into the landmark scene shown in a georeferenced image via a feedback control loop, which is driven by the output of an aerial image registration. To pursue a real-time application, we design and implement a speeded-up-robust-features (SURF)-based image registration algorithm that focuses efficiency and robustness under a 2D geometric transformation. A linear UAV controller with signals of four degrees of freedom is derived from the estimated transformation matrix. The approach is validated in a virtual simulation environment, with experimental results demonstrating the effectiveness and robustness of the proposed UAV self-localization system.

Technology Stack Selection Model for Software Design of Digital Platforms

The article is dedicated to the development of a mathematical model and methodology for evaluating the effectiveness of integrating information technology solutions into digital platforms using virtual simulation infrastructures. The task of selecting a stack of technologies is formulated as the task of selecting elements from sets of possible solutions. This allows us to develop a mathematically unified approach to evaluating the effectiveness of different solutions, such as choosing programming languages, choosing Database Management System (DBMS), choosing operating systems and data technologies, and choosing the frameworks used. Introduced technology compatibility operation and decomposition of the evaluation of the efficiency of the technology stack at the stages of the life cycle of the digital platform development allowed us to reduce the computational complexity of the formation of the technology stack. A methodology based on performance assessments for experimental research in a virtual software-configurable simulation environment has been proposed. The developed solution allows the evaluation of the performance of the digital platform before its final implementation, while reducing the cost of conducting an experiment to assess the characteristics of the digital platform. It is proposed to compare the characteristics of digital platform efficiency based on the use of fuzzy logic, providing the software developer with an intuitive tool to support decision-making on the inclusion of the solution in the technology stack.

Development and Evaluation of Path and Speed Profile Planning and Tracking Control for an Autonomous Shuttle Using a Realistic, Virtual Simulation Environment

This paper is motivated by the autonomous shuttle service that operates in the geo-fenced Linden Residential Area of Columbus, Ohio that links residents to the two nearby locations of opportunity of a community center and a transit hub. This paper focuses on path planning and path tracking of an autonomous shuttle which are its most fundamental autonomous driving functions. Path planning is based on improving efficiency of computation and smoothness of path. Velocity planning is based on obeying speed limits, limiting longitudinal acceleration along straight segments and lateral acceleration during curved segments for improved ride comfort of the passengers. Path tracking control focuses on robust implementation that keeps accuracy of path following in the presence of uncertainties and variations in speed. A realistic, 3D virtual simulation environment of the actual geo-fenced urban area used here is built for evaluating and developing the path planning and path tracking functions of this paper. The same environment can also be used for developing and evaluating other autonomous driving functions with the capability of generating complicated traffic scenarios. The path tacking control results are compared with those of the pure pursuit path tracking algorithm of the open source and publicly available Autoware autonomous driving interface for the Robot Operating System.

A review of collision detection for deformable objects

AbstractIn the process of simulating and modeling real objects, the phenomenon of objects penetrating each other may occur in the model, which is unrealistic and then the research of collision detection (CD) is generated. As a bottleneck of virtual environment simulation, researchers have conducted in‐depth research on CD, especially the CD of deformable objects. In this paper, we briefly review the related research on CD of deformable objects regarding relevant literature. First, we briefly introduce previous reviews of CD. Second, we review the popular research methods and limitations of CD between deformable objects. Third, we review the popular research methods and limitations of self‐collision detection in deformable objects. Finally, we discuss future directions of development. This review can be used as a reference for the application of CD in all directions.