A virtual computerized numerical control C CNC） processing system is built for spiral bevel and hypoid gears. The pre-designed process of the solution to locate the way of realization is investigated. A kind of combi...A virtual computerized numerical control C CNC） processing system is built for spiral bevel and hypoid gears. The pre-designed process of the solution to locate the way of realization is investigated. A kind of combined programming method and principle of solid modeling are chosen. Multienvironmental programming thought and the inter-connected mechanisms between different environments are applied in the proposed system. The problems of data exchange and compatibility of modules are settled. Environment of the system is founded with object oriented programming thought. AutoCAD is located as the graphic environment. Matlab is used for editing the computation module. Virtual C ＋＋6.0 is the realization environment of the main module. Windows is the platform for realizing the multi-environmental method. Through establishing the virtual system based windows message handling mechanism and the component object model, the application of multienvironmental programming is realized in the manufacture system simulation. The virtual gear product can be achieved in the accomplished software.展开更多
With the rapid development of intelligent cyber-physical systems(ICPS),diverse services with varying Quality of Service(QoS)requirements have brought great challenges to traditional network resource allocation.Further...With the rapid development of intelligent cyber-physical systems(ICPS),diverse services with varying Quality of Service(QoS)requirements have brought great challenges to traditional network resource allocation.Furthermore,given the open environment and a multitude of devices,enhancing the security of ICPS is an urgent concern.To address these issues,this paper proposes a novel trusted virtual network embedding(T-VNE)approach for ICPS based combining blockchain and edge computing technologies.Additionally,the proposed algorithm leverages a deep reinforcement learning(DRL)model to optimize decision-making processes.It employs the policygradient-based agent to compute candidate embedding nodes and utilizes a breadth-first search(BFS)algorithm to determine the optimal embedding paths.Finally,through simulation experiments,the efficacy of the proposed method was validated,demonstrating outstanding performance in terms of security,revenue generation,and virtual network request(VNR)acceptance rate.展开更多
This research pioneers the integration of geographic information systems(GIS)and 3D modeling within a virtual reality(VR)framework to assess the viability and planning of a 20 MW hybrid wind-solarphotovoltaic(PV)syste...This research pioneers the integration of geographic information systems(GIS)and 3D modeling within a virtual reality(VR)framework to assess the viability and planning of a 20 MW hybrid wind-solarphotovoltaic(PV)system connected to the local grid.The study focuses on Dakhla,Morocco,a region with vast untapped renewable energy potential.By leveraging GIS,we are innovatively analyzing geographical and environmental factors that influence optimal site selection and system design.The incorporation of VR technologies offers an unprecedented level of realism and immersion,allowing stakeholders to virtually experience the project's impact and design in a dynamic,interactive environment.This novel methodology includes extensive data collection,advanced modeling,and simulations,ensuring that the hybrid system is precisely tailored to the unique climatic and environmental conditions of Dakhla.Our analysis reveals that the region possesses a photovoltaic solar potential of approximately2400 k Wh/m^(2) per year,with an average annual wind power density of about 434 W/m^(2) at an 80-meter hub height.Productivity simulations indicate that the 20 MW hybrid system could generate approximately 60 GWh of energy per year and 1369 GWh over its 25-year lifespan.To validate these findings,we employed the System Advisor Model(SAM)software and the Global Solar Photovoltaic Atlas platform.This comprehensive and interdisciplinary approach not only provides a robust assessment of the system's feasibility but also offers valuable insights into its potential socio-economic and environmental impact.展开更多
To address the challenges of insufficient visualization in the industrial robot assembly operation system and the limitation of visualizing only geometric attributes of physical properties,a method is proposed for con...To address the challenges of insufficient visualization in the industrial robot assembly operation system and the limitation of visualizing only geometric attributes of physical properties,a method is proposed for constructing an industrial robot assembly system based on virtual reality technology.Focusing on the shaft hole assembly,the mechanical characteristics of the industrial robot shaft hole assembly process are analyzed and a dynamic model is established for shaft hole assembly operations.The key elements of virtual assembly operations for industrial robots are summarized and a five-dimensional model is proposed for industrial robot virtual operations.Utilizing the Unity3D engine based on the 5-D model for industrial robot virtual operations,an industrial robot shaft hole assembly system is developed.This system enables virtual assembly operations,displays physical attributes,and provides valuable references for the research of virtual systems.展开更多
Objective:We aimed to perform a systematic review and meta-analysis to assess the efficacy of virtual reality(VR)distraction technologies in managing pain and anxiety in patients undergoing cystoscopy procedures.Metho...Objective:We aimed to perform a systematic review and meta-analysis to assess the efficacy of virtual reality(VR)distraction technologies in managing pain and anxiety in patients undergoing cystoscopy procedures.Methods:We searched PubMed,Embase,and the Cochrane Central Register of Controlled Trials from inception to July 2024,for studies comparing the use of VR distraction technologies versus no VR distraction in patients undergoing cystoscopy.The primary endpoints evaluated were patient-reported anxiety and procedural pain scores,and post-procedural heart rate(HR).Standardized mean differences(SMDs)and their 95%confidence intervals(CIs)were computed with the use of a random-effects model.The statistical analysis was conducted using Review Manager 5.4.Results:A total of 575 patients from four randomized controlled trials were included,of whom 289(50%)underwent the cystoscopy procedure using VR distraction technologies.The mean age of all patients was 57.25 years old,and 395(69%)of them were male.In our pooled analysis,we did not observe a statistically significant reduction in patient-reported procedural pain(SMD=0.16;95%CI=0.32-0.00;p=0.060;I^(2)=0%),anxiety(SMD=0.37;95%CI=1.65-0.90;p=0.6;I^(2)=93%),or post-procedural HR(SMD=0.58;95%CI=1.62-0.45;p=0.3;I^(2)=97%).Conclusion:In this comprehensive meta-analysis comprising 575 patients who underwent cystoscopy,the use of VR was not associated with a significant difference in pain,anxiety,or HR levels.展开更多
The integration of Human-Robot Collaboration(HRC)into Virtual Reality(VR)technology is transforming industries by enhancing workforce skills,improving safety,and optimizing operational processes and efficiency through...The integration of Human-Robot Collaboration(HRC)into Virtual Reality(VR)technology is transforming industries by enhancing workforce skills,improving safety,and optimizing operational processes and efficiency through realistic simulations of industry-specific scenarios.Despite the growing adoption of VR integrated with HRC,comprehensive reviews of current research in HRC-VR within the construction and manufacturing fields are lacking.This review examines the latest advances in designing and implementing HRC using VR technology in these industries.The aim is to address the application domains of HRC-VR,types of robots used,VR setups,and software solutions used.To achieve this,a systematic literature review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology was conducted on the Web of Science and Google Scholar databases,analyzing 383 articles and selecting 53 papers that met the established selection criteria.The findings emphasize a significant focus on enhancing human-robot interaction with a trend toward using immersive VR experiences and interactive 3D content creation tools.However,the integration of HRC with VR,especially in the dynamic construction environment,presents unique challenges and opportunities for future research,including developing more realistic simulations and adaptable robot systems.This paper offers insights for researchers,practitioners,educators,industry professionals,and policymakers interested in leveraging the integration of HRC with VR in construction and manufacturing industries.展开更多
This article discusses the detailed examination of the engineering design and implementation process for direct Train-to-Train(T2T)communication within a wireless train backbone network in the context of a virtual cou...This article discusses the detailed examination of the engineering design and implementation process for direct Train-to-Train(T2T)communication within a wireless train backbone network in the context of a virtual coupling scenario.The article proposed several critical aspects,including the optimization of transmission data requirements,which is essential to ensure that communication between trains is efficient and reliable.The design of the T2T wireless communication subsystem is discussed in detail,outlining the technical specifications,protocols,and technologies employed to facilitate wireless communication between multiple trains.Additionally,the article presents a thorough analysis of the data collected during real-world train experiments,highlighting the performance metrics and challenges encountered during testing.This empirical data not only validates the effectiveness of the proposed design but also serves as a crucial reference for future advancements in T2T wireless communication systems.By combining both theoretical principles and practical outcomes,the article offers insights that will aid engineers and researchers in developing robust and efficient wireless communication systems for next-generation train operations.展开更多
Virtual reality(VR)technology revitalises rehabilitation training by creating rich,interactive virtual rehabilitation scenes and tasks that deeply engage patients.Robotics with immersive VR environments have the poten...Virtual reality(VR)technology revitalises rehabilitation training by creating rich,interactive virtual rehabilitation scenes and tasks that deeply engage patients.Robotics with immersive VR environments have the potential to significantly enhance the sense of immersion for patients during training.This paper proposes a rehabilitation robot system.The system integrates a VR environment,the exoskeleton entity,and research on rehabilitation assessment metrics derived from surface electromyographic signal(sEMG).Employing more realistic and engaging virtual stimuli,this method guides patients to actively participate,thereby enhancing the effectiveness of neural connection reconstruction—an essential aspect of rehabilitation.Furthermore,this study introduces a muscle activation model that merges linear and non-linear states of muscle,avoiding the impact of non-linear shape factors on model accuracy present in traditional models.A muscle strength assessment model based on optimised generalised regression(WOAGRNN)is also proposed,with a root mean square error of 0.017,347 and a mean absolute percentage error of 1.2461%,serving as critical assessment indicators for the effectiveness of rehabilitation.Finally,the system is preliminarily applied in human movement experiments,validating the practicality and potential effectiveness of VRcentred rehabilitation strategies in medical recovery.展开更多
This paper introduces the experience and practice in constructing the practical teaching system for the course“Electric Machine and Drive.”In response to the current status of cultivating innovative practical abilit...This paper introduces the experience and practice in constructing the practical teaching system for the course“Electric Machine and Drive.”In response to the current status of cultivating innovative practical abilities among electrical engineering majors,based on the independently developed virtual simulation experimental teaching platform for Electric Machine and Drive,a stepped practical teaching process consisting of“classroom teaching-experimental teaching-comprehensive training-scientific inquiry”has been elaborately designed.A hierarchical practical teaching model for the second classroom has also been established.With teaching objectives as the optimization index,the teaching content,methods and means have been optimized;the teaching process has been organized and implemented in the form of team collaboration,thus constructing a comprehensive,stepped,hierarchical,and closed-loop innovative practical teaching system.This achievement provides references and assistance for the practical teaching of the same or similar majors in other colleges and universities.展开更多
The problem of high-performance tracking controlfor the lower-triangular systems with unknown sign-switchingvirtual control coefficients as well as unmatched disturbances isinvestigated in this paper.Instead of the on...The problem of high-performance tracking controlfor the lower-triangular systems with unknown sign-switchingvirtual control coefficients as well as unmatched disturbances isinvestigated in this paper.Instead of the online estimation algorithm,the sliding mode method and the Nussbaum gain technique,a group of orientation functions are employed to handlethe unknown sign-switching virtual control coefficients.The controllaw is combined with the orientation functions and the barrierfunctions lumped in a recursive manner.It achieves outputtracking with the preassigned rate,overshoot,and accuracy.Incontrast with the existing solutions,it is effective for the nearlymodel-free case,with the requirement for information of neitherthe system nonlinearities nor their bounding functions of theplant,nor the bounds of the disturbances.In addition,our controllerexhibits significant simplicity,without parameter identification,disturbance estimation,function approximation,derivativecalculation,dynamic surfaces,or command filtering.Twosimulation examples are conducted to substantiate the efficacyand advantages of our approach.展开更多
In the era of big data,data-driven technologies are increasingly leveraged by industry to facilitate autonomous learning and intelligent decision-making.However,the challenge of“small samples in big data”emerges whe...In the era of big data,data-driven technologies are increasingly leveraged by industry to facilitate autonomous learning and intelligent decision-making.However,the challenge of“small samples in big data”emerges when datasets lack the comprehensive information necessary for addressing complex scenarios,which hampers adaptability.Thus,enhancing data completeness is essential.Knowledge-guided virtual sample generation transforms domain knowledge into extensive virtual datasets,thereby reducing dependence on limited real samples and enabling zero-sample fault diagnosis.This study used building air conditioning systems as a case study.We innovatively used the large language model(LLM)to acquire domain knowledge for sample generation,significantly lowering knowledge acquisition costs and establishing a generalized framework for knowledge acquisition in engineering applications.This acquired knowledge guided the design of diffusion boundaries in mega-trend diffusion(MTD),while the Monte Carlo method was used to sample within the diffusion function to create information-rich virtual samples.Additionally,a noise-adding technique was introduced to enhance the information entropy of these samples,thereby improving the robustness of neural networks trained with them.Experimental results showed that training the diagnostic model exclusively with virtual samples achieved an accuracy of 72.80%,significantly surpassing traditional small-sample supervised learning in terms of generalization.This underscores the quality and completeness of the generated virtual samples.展开更多
With the rapid integration of renewable energy sources,modern power systems are increasingly challenged by heightened volatility and uncertainty.Doubly-fed variable-speed pumped storage units(DFVS-PSUs)have emerged as...With the rapid integration of renewable energy sources,modern power systems are increasingly challenged by heightened volatility and uncertainty.Doubly-fed variable-speed pumped storage units(DFVS-PSUs)have emerged as promising technologies for mitigating grid oscillations and enhancing system flexibility.However,the excitation converters in DFVS-PSUs are prone to significant issues such as elevated common-mode voltage(CMV)and neutral-point voltage(NPV)fluctuations,which can lead to electromagnetic interference and degrade transient performance.To address these challenges,an optimized virtual space vector pulse width modulation(OVSVPWM)strategy is proposed,aiming to suppress CMV and NPV simultaneously through coordinated multi-objective control.Specifically,a dynamic feedback mechanism is introduced to adjust the balancing factor of basic vectors in the synthesized virtual small vector in real-time,achieving autonomous balancing of the NPV.To address the excessive switching actions introduced by the OVSVPWM strategy,a phase duty ratio-based sequence reconstruction method is adopted,which reduces the total number of switching actions to half of the original.A zero-level buffering scheme is employed to reconstruct the single-phase voltage-level output sequence,achieving peak CMV suppression down to udc/6.Simulation results demonstrate that the proposed strategy significantly improves electromagnetic compatibility and operational stability while maintaining high power quality.展开更多
With the increasing integration of renewable energy,microgrids are increasingly facing stability challenges,primarily due to the lack of inherent inertia in inverter-dominated systems,which is traditionally provided b...With the increasing integration of renewable energy,microgrids are increasingly facing stability challenges,primarily due to the lack of inherent inertia in inverter-dominated systems,which is traditionally provided by synchronous generators.To address this critical issue,Virtual Synchronous Generator(VSG)technology has emerged as a highly promising solution by emulating the inertia and damping characteristics of conventional synchronous generators.To enhance the operational efficiency of virtual synchronous generators(VSGs),this study employs smallsignal modeling analysis,root locus methods,and synchronous generator power-angle characteristic analysis to comprehensively evaluate how virtual inertia and damping coefficients affect frequency stability and power output during transient processes.Based on these analyses,an adaptive control strategy is proposed:increasing the virtual inertia when the rotor angular velocity undergoes rapid changes,while strengthening the damping coefficient when the speed deviation exceeds a certain threshold to suppress angular velocity oscillations.To validate the effectiveness of the proposed method,a grid-connected VSG simulation platform was developed inMATLAB/Simulink.Comparative simulations demonstrate that the proposed adaptive control strategy outperforms conventional VSGmethods by significantly reducing grid frequency deviations and shortening active power response time during active power command changes and load disturbances.This approach enhances microgrid stability and dynamic performance,confirming its viability for renewable-dominant power systems.Future work should focus on experimental validation and real-world parameter optimization,while further exploring the strategy’s effectiveness in improvingVSG low-voltage ride-through(LVRT)capability and power-sharing applications in multi-parallel configurations.展开更多
Background:Submarine personnel often experience insomnia and reduced psychological resilience due to extended deployments in confined,high-stress environments.Effective non-pharmacological interventions are needed to ...Background:Submarine personnel often experience insomnia and reduced psychological resilience due to extended deployments in confined,high-stress environments.Effective non-pharmacological interventions are needed to improve sleep quality and resilience in this population.This study aimed to investigate the effect of virtual reality(VR)combined with forest therapy interventions on psychological resilience and sleep quality among submarine personnel with insomnia symptoms.Methods:Using convenience sampling,92 submarine personnel with insomnia symptoms undergoing recuperation at a PLA sanatorium between July 2023 and May 2025 were randomly allocated to experimental and control groups(n=46 each).The control group received forest therapy intervention,while the intervention group received combined VR and forest therapy interventions.Pre-and post-intervention assessments were conducted using the Pittsburgh Sleep Quality Index(PSQI)and Connor-Davidson Resilience Scale(CD-RISC).Results:There is no significant differences between two groups before the intervention on sleep or psychological resilience.Both groups showed significant pre-to post-intervention improvements in sleep and resilience;however,mixed-ANOVA results showed that the intervention(VR+forest therapy)group achieved significantly better outcomes than the control group at post-intervention after Bonferroni correction,including lower PSQI total and key component scores(subjective sleep quality,sleep efficiency,daytime dysfunction)and higher CD-RISC resilience scores.Conclusions:The integration of virtual reality and forest therapy effectively improved sleep quality and psychological resilience among submarine personnel with insomnia symptoms.This combined intervention shows promise as a non-pharmacological approach in military healthcare settings;however,further studies are needed to validate and generalize these findings.展开更多
Objectives This scoping review aimed to identify and summarize the current research on virtual reality(VR)technologies used for health education in cancer patients,as well as to identify key areas of application.Metho...Objectives This scoping review aimed to identify and summarize the current research on virtual reality(VR)technologies used for health education in cancer patients,as well as to identify key areas of application.Methods In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines,a comprehensive literature search was performed across 11 electronic databases and gray literature sources from inception to 12 September 2025.Studies employing immersive VR tools to improve health education outcomes in cancer patients were included.Data extraction and thematic synthesis were conducted to map evidence regarding VR modalities,educational applications,and outcome measures.Results Twenty-eight studies met the inclusion criteria.VR was applied across four primary educational scenarios,including radiotherapy,chemotherapy,surgery,and healthy behavior(including rehabilitation,smoking cessation,and self-management).Eight distinct VR modalities were identified,namely VR videos,virtual environments,virtual environment for radiotherapy training(VERT),VR interactions,3D models,VR games,VR non-player characters(VR NPCs),and virtual libraries.Among these,VR videos(50.0%),virtual environments(46.4%),and VR interactions(28.6%)were the most frequently employed.The interventions led to significant improvements in patient knowledge,skills,attitudes,health behaviors,and psychological well-being.A clear evolution in VR educational approaches has been observed,shifting from static environmental familiarization toward interactive,gamified,and intelligence-driven experiences.Nevertheless,notable gaps remain regarding safety protocols and data privacy protections,with only a minority of studies addressing these issues.Conclusions VR technologies demonstrate considerable promise as an innovative educational tool in oncology care,enhancing patient understanding,psychological preparedness,and engagement throughout the cancer journey.Future implementation must address infrastructural,ethical,and user-centered design barriers to facilitate the scalable and sustainable integration of this approach into clinical practice.展开更多
Detector and event visualization are crucial components of high-energy physics(HEP)experimental software.Virtual reality(VR)technologies and multimedia development platforms,such as Unity,offer enhanced display effect...Detector and event visualization are crucial components of high-energy physics(HEP)experimental software.Virtual reality(VR)technologies and multimedia development platforms,such as Unity,offer enhanced display effects and flexible extensibility for visualization in HEP experiments.In this study,we present a VR-based method for detector and event displays in the Jiangmen Underground Neutrino Observatory(JUNO)experiment.This method shares the same detector geometry descriptions and event data model as those in the offline software and provides the necessary data conversion interfaces.The VR methodology facilitates an immersive exploration of the virtual environment in JUNO,enabling users to investigate the detector geometry,visualize event data,and tune the detector simulation and event reconstruction algorithms.Additionally,this approach supports applications in data monitoring,physics data analysis,and public outreach initiatives.展开更多
Objective:Nurse-led virtual outpatient clinics are now a familiar component of healthcare delivery across many disciplines,including cancer care,or thopedics,rheumatology,and gastroenterology.However,establishing a nu...Objective:Nurse-led virtual outpatient clinics are now a familiar component of healthcare delivery across many disciplines,including cancer care,or thopedics,rheumatology,and gastroenterology.However,establishing a nurse-led vir tual clinic is challenging for nursing management,par ticularly regarding resources.We aimed to investigate nursing practices and processes and patient experiences in relation to vir tual outpatient clinics.Methods:This was a cross-sectional,descriptive study using mixed data collection methods.Patients(n=324)from 4 specialist clinics completed the Virtual Clinics Patient Satisfaction Questionnaire(VCSQ)survey.Five Nurse Specialists participated in a focus group interview.Results:Most participants(86.3%)reported being satisfied/very satisfied with the virtual clinics,particularly those that were nurse-led.Nurse specialists identified electronic health records(EHRs)and additional IT and administrative support as important for efficiency and effectiveness of the clinics.Conclusions:Nurse-led virtual clinics can be an effective and efficient way to provide care to patients.Nurse managers need to ensure supportive structures are in place,for example,dedicated administrators,IT support and infrastructure,education/training,and relevant policies/procedures.The success of nurse-led virtual services requires key infrastructure to support nursing staff and sustain this service.展开更多
Virtual power plant(VPP)integrates a variety of distributed renewable energy and energy storage to participate in electricity market transactions,promote the consumption of renewable energy,and improve economic effici...Virtual power plant(VPP)integrates a variety of distributed renewable energy and energy storage to participate in electricity market transactions,promote the consumption of renewable energy,and improve economic efficiency.In this paper,aiming at the uncertainty of distributed wind power and photovoltaic output,considering the coupling relationship between power,carbon trading,and green cardmarket,the optimal operationmodel and bidding scheme of VPP in spot market,carbon trading market,and green card market are established.On this basis,through the Shapley value and independent risk contribution theory in cooperative game theory,the quantitative analysis of the total income and risk contribution of various distributed resources in the virtual power plant is realized.Moreover,the scheduling strategies of virtual power plants under different risk preferences are systematically compared,and the feasibility and accuracy of the combination of Shapley value and independent risk contribution theory in ensuring fair income distribution and reasonable risk assessment are emphasized.A comprehensive solution for virtual power plants in the multi-market environment is constructed,which integrates operation strategy,income distribution mechanism,and risk control system into a unified analysis framework.Through the simulation of multi-scenario examples,the CPLEXsolver inMATLAB software is used to optimize themodel.The proposed joint optimization scheme can increase the profit of VPP participating in carbon trading and green certificate market by 29%.The total revenue of distributed resources managed by VPP is 9%higher than that of individual participation.展开更多
Small datasets are often challenging due to their limited sample size.This research introduces a novel solution to these problems:average linkage virtual sample generation(ALVSG).ALVSG leverages the underlying data st...Small datasets are often challenging due to their limited sample size.This research introduces a novel solution to these problems:average linkage virtual sample generation(ALVSG).ALVSG leverages the underlying data structure to create virtual samples,which can be used to augment the original dataset.The ALVSG process consists of two steps.First,an average-linkage clustering technique is applied to the dataset to create a dendrogram.The dendrogram represents the hierarchical structure of the dataset,with each merging operation regarded as a linkage.Next,the linkages are combined into an average-based dataset,which serves as a new representation of the dataset.The second step in the ALVSG process involves generating virtual samples using the average-based dataset.The research project generates a set of 100 virtual samples by uniformly distributing them within the provided boundary.These virtual samples are then added to the original dataset,creating a more extensive dataset with improved generalization performance.The efficacy of the ALVSG approach is validated through resampling experiments and t-tests conducted on two small real-world datasets.The experiments are conducted on three forecasting models:the support vector machine for regression(SVR),the deep learning model(DL),and XGBoost.The results show that the ALVSG approach outperforms the baseline methods in terms of mean square error(MSE),root mean square error(RMSE),and mean absolute error(MAE).展开更多
Researchers are increasingly focused on enabling groups of multiple unmanned vehicles to operate cohesively in complex,real-world environments,where coordinated formation control and obstacle avoidance are essential f...Researchers are increasingly focused on enabling groups of multiple unmanned vehicles to operate cohesively in complex,real-world environments,where coordinated formation control and obstacle avoidance are essential for executing sophisticated collective tasks.This paper presents a Distributed Formation Control and Obstacle Avoidance(DFCOA)framework for multi-unmanned ground vehicles(UGV).DFCOA integrates a virtual leader structure for global guidance,an improved A^(*)path planning algorithm with an advanced cost function for efficient path planning,and a repulsive-force-based improved vector field histogram star(VFH^(*))technique for collision avoidance.The virtual leader generates a reference trajectory while enabling distributed execution;the improved A^(*)algorithm reduces planning time and number of nodes to determine the shortest path from the starting position to the goal;and the improved VFH^(*)uses 2D LiDAR data with inter-agent repulsive force to simultaneously avoid collision with obstacles and maintain safe inter-vehicle distances.The formation stability of the proposed DFCOA reaches 95.8%and 94.6%in two scenarios,with root mean square(RMS)centroid errors of 0.9516 and 1.0008 m,respectively.Velocity tracking is precise(velocity centroid error RMS of 0.2699 and 0.1700 m/s),and linear velocities closely match the desired 0.3 m/s.Safety metrics showed average collision risks of 0.7773 and 0.5143,with minimum inter-vehicle distances of 0.4702 and 0.8763 m,confirming collision-free navigation of four UGVs.DFCOA outperforms conventional methods in formation stability,path efficiency,and scalability,proving its suitability for decentralized multi-UGV applications.展开更多
基金Supported by Natural Science Foundation of China (No. 50475117).
文摘A virtual computerized numerical control C CNC） processing system is built for spiral bevel and hypoid gears. The pre-designed process of the solution to locate the way of realization is investigated. A kind of combined programming method and principle of solid modeling are chosen. Multienvironmental programming thought and the inter-connected mechanisms between different environments are applied in the proposed system. The problems of data exchange and compatibility of modules are settled. Environment of the system is founded with object oriented programming thought. AutoCAD is located as the graphic environment. Matlab is used for editing the computation module. Virtual C ＋＋6.0 is the realization environment of the main module. Windows is the platform for realizing the multi-environmental method. Through establishing the virtual system based windows message handling mechanism and the component object model, the application of multienvironmental programming is realized in the manufacture system simulation. The virtual gear product can be achieved in the accomplished software.
基金supported by the National Natural Science Foundation of China under Grant 62471493supported by the Natural Science Foundation of Shandong Province under Grant ZR2023LZH017,ZR2024MF066。
文摘With the rapid development of intelligent cyber-physical systems(ICPS),diverse services with varying Quality of Service(QoS)requirements have brought great challenges to traditional network resource allocation.Furthermore,given the open environment and a multitude of devices,enhancing the security of ICPS is an urgent concern.To address these issues,this paper proposes a novel trusted virtual network embedding(T-VNE)approach for ICPS based combining blockchain and edge computing technologies.Additionally,the proposed algorithm leverages a deep reinforcement learning(DRL)model to optimize decision-making processes.It employs the policygradient-based agent to compute candidate embedding nodes and utilizes a breadth-first search(BFS)algorithm to determine the optimal embedding paths.Finally,through simulation experiments,the efficacy of the proposed method was validated,demonstrating outstanding performance in terms of security,revenue generation,and virtual network request(VNR)acceptance rate.
文摘This research pioneers the integration of geographic information systems(GIS)and 3D modeling within a virtual reality(VR)framework to assess the viability and planning of a 20 MW hybrid wind-solarphotovoltaic(PV)system connected to the local grid.The study focuses on Dakhla,Morocco,a region with vast untapped renewable energy potential.By leveraging GIS,we are innovatively analyzing geographical and environmental factors that influence optimal site selection and system design.The incorporation of VR technologies offers an unprecedented level of realism and immersion,allowing stakeholders to virtually experience the project's impact and design in a dynamic,interactive environment.This novel methodology includes extensive data collection,advanced modeling,and simulations,ensuring that the hybrid system is precisely tailored to the unique climatic and environmental conditions of Dakhla.Our analysis reveals that the region possesses a photovoltaic solar potential of approximately2400 k Wh/m^(2) per year,with an average annual wind power density of about 434 W/m^(2) at an 80-meter hub height.Productivity simulations indicate that the 20 MW hybrid system could generate approximately 60 GWh of energy per year and 1369 GWh over its 25-year lifespan.To validate these findings,we employed the System Advisor Model(SAM)software and the Global Solar Photovoltaic Atlas platform.This comprehensive and interdisciplinary approach not only provides a robust assessment of the system's feasibility but also offers valuable insights into its potential socio-economic and environmental impact.
基金Sponsored by the National Natural Science Foundation of China(Grant No.52005003)the Science and Technology Planning Project of Wuhu City(Grant No.2022jc41)。
文摘To address the challenges of insufficient visualization in the industrial robot assembly operation system and the limitation of visualizing only geometric attributes of physical properties,a method is proposed for constructing an industrial robot assembly system based on virtual reality technology.Focusing on the shaft hole assembly,the mechanical characteristics of the industrial robot shaft hole assembly process are analyzed and a dynamic model is established for shaft hole assembly operations.The key elements of virtual assembly operations for industrial robots are summarized and a five-dimensional model is proposed for industrial robot virtual operations.Utilizing the Unity3D engine based on the 5-D model for industrial robot virtual operations,an industrial robot shaft hole assembly system is developed.This system enables virtual assembly operations,displays physical attributes,and provides valuable references for the research of virtual systems.
文摘Objective:We aimed to perform a systematic review and meta-analysis to assess the efficacy of virtual reality(VR)distraction technologies in managing pain and anxiety in patients undergoing cystoscopy procedures.Methods:We searched PubMed,Embase,and the Cochrane Central Register of Controlled Trials from inception to July 2024,for studies comparing the use of VR distraction technologies versus no VR distraction in patients undergoing cystoscopy.The primary endpoints evaluated were patient-reported anxiety and procedural pain scores,and post-procedural heart rate(HR).Standardized mean differences(SMDs)and their 95%confidence intervals(CIs)were computed with the use of a random-effects model.The statistical analysis was conducted using Review Manager 5.4.Results:A total of 575 patients from four randomized controlled trials were included,of whom 289(50%)underwent the cystoscopy procedure using VR distraction technologies.The mean age of all patients was 57.25 years old,and 395(69%)of them were male.In our pooled analysis,we did not observe a statistically significant reduction in patient-reported procedural pain(SMD=0.16;95%CI=0.32-0.00;p=0.060;I^(2)=0%),anxiety(SMD=0.37;95%CI=1.65-0.90;p=0.6;I^(2)=93%),or post-procedural HR(SMD=0.58;95%CI=1.62-0.45;p=0.3;I^(2)=97%).Conclusion:In this comprehensive meta-analysis comprising 575 patients who underwent cystoscopy,the use of VR was not associated with a significant difference in pain,anxiety,or HR levels.
基金Supported by National Science Foundation under Grant No.2222881.
文摘The integration of Human-Robot Collaboration(HRC)into Virtual Reality(VR)technology is transforming industries by enhancing workforce skills,improving safety,and optimizing operational processes and efficiency through realistic simulations of industry-specific scenarios.Despite the growing adoption of VR integrated with HRC,comprehensive reviews of current research in HRC-VR within the construction and manufacturing fields are lacking.This review examines the latest advances in designing and implementing HRC using VR technology in these industries.The aim is to address the application domains of HRC-VR,types of robots used,VR setups,and software solutions used.To achieve this,a systematic literature review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology was conducted on the Web of Science and Google Scholar databases,analyzing 383 articles and selecting 53 papers that met the established selection criteria.The findings emphasize a significant focus on enhancing human-robot interaction with a trend toward using immersive VR experiences and interactive 3D content creation tools.However,the integration of HRC with VR,especially in the dynamic construction environment,presents unique challenges and opportunities for future research,including developing more realistic simulations and adaptable robot systems.This paper offers insights for researchers,practitioners,educators,industry professionals,and policymakers interested in leveraging the integration of HRC with VR in construction and manufacturing industries.
基金supported by the National Key R&D Program of China(2021YFF0501103).
文摘This article discusses the detailed examination of the engineering design and implementation process for direct Train-to-Train(T2T)communication within a wireless train backbone network in the context of a virtual coupling scenario.The article proposed several critical aspects,including the optimization of transmission data requirements,which is essential to ensure that communication between trains is efficient and reliable.The design of the T2T wireless communication subsystem is discussed in detail,outlining the technical specifications,protocols,and technologies employed to facilitate wireless communication between multiple trains.Additionally,the article presents a thorough analysis of the data collected during real-world train experiments,highlighting the performance metrics and challenges encountered during testing.This empirical data not only validates the effectiveness of the proposed design but also serves as a crucial reference for future advancements in T2T wireless communication systems.By combining both theoretical principles and practical outcomes,the article offers insights that will aid engineers and researchers in developing robust and efficient wireless communication systems for next-generation train operations.
基金National Key Research and Development Program of China,Grant/Award Number:2022YFB4700701National Outstanding Youth Science Fund Project of National Natural Science Foundation of China,Grant/Award Number:52025054。
文摘Virtual reality(VR)technology revitalises rehabilitation training by creating rich,interactive virtual rehabilitation scenes and tasks that deeply engage patients.Robotics with immersive VR environments have the potential to significantly enhance the sense of immersion for patients during training.This paper proposes a rehabilitation robot system.The system integrates a VR environment,the exoskeleton entity,and research on rehabilitation assessment metrics derived from surface electromyographic signal(sEMG).Employing more realistic and engaging virtual stimuli,this method guides patients to actively participate,thereby enhancing the effectiveness of neural connection reconstruction—an essential aspect of rehabilitation.Furthermore,this study introduces a muscle activation model that merges linear and non-linear states of muscle,avoiding the impact of non-linear shape factors on model accuracy present in traditional models.A muscle strength assessment model based on optimised generalised regression(WOAGRNN)is also proposed,with a root mean square error of 0.017,347 and a mean absolute percentage error of 1.2461%,serving as critical assessment indicators for the effectiveness of rehabilitation.Finally,the system is preliminarily applied in human movement experiments,validating the practicality and potential effectiveness of VRcentred rehabilitation strategies in medical recovery.
基金Project of the 14th Five-Year Plan for Educational Science in Liaoning Province(JG24DB234)Project of Graduate Education and Teaching Reform Research in Liaoning Province(LNYJG2023115)。
文摘This paper introduces the experience and practice in constructing the practical teaching system for the course“Electric Machine and Drive.”In response to the current status of cultivating innovative practical abilities among electrical engineering majors,based on the independently developed virtual simulation experimental teaching platform for Electric Machine and Drive,a stepped practical teaching process consisting of“classroom teaching-experimental teaching-comprehensive training-scientific inquiry”has been elaborately designed.A hierarchical practical teaching model for the second classroom has also been established.With teaching objectives as the optimization index,the teaching content,methods and means have been optimized;the teaching process has been organized and implemented in the form of team collaboration,thus constructing a comprehensive,stepped,hierarchical,and closed-loop innovative practical teaching system.This achievement provides references and assistance for the practical teaching of the same or similar majors in other colleges and universities.
基金supported in part by the National Natural Science Foundation of China(61991404,62473089)the Research Program of the Liaoning Liaohe Laboratory(LLL23ZZ-05-01)+6 种基金the Key Research and Development Program of Liaoning Province of China(2023JH26/10200011)the 111 Project 2.0 of China(B08015)the National Key Research and Development Program of China(2022YFB3305905)the Xingliao Talent Program of Liaoning Province of China(XLYC2203130)the Natural Science Foundation of Liaoning Province of China(2024JH3/10200012,2023-MS-087)the Open Research Project of the State Key Laboratory of Industrial Control Technology of China(ICT2024B12)the Fundamental Research Funds for the Central Universities of China(N2108003,N2424004).
文摘The problem of high-performance tracking controlfor the lower-triangular systems with unknown sign-switchingvirtual control coefficients as well as unmatched disturbances isinvestigated in this paper.Instead of the online estimation algorithm,the sliding mode method and the Nussbaum gain technique,a group of orientation functions are employed to handlethe unknown sign-switching virtual control coefficients.The controllaw is combined with the orientation functions and the barrierfunctions lumped in a recursive manner.It achieves outputtracking with the preassigned rate,overshoot,and accuracy.Incontrast with the existing solutions,it is effective for the nearlymodel-free case,with the requirement for information of neitherthe system nonlinearities nor their bounding functions of theplant,nor the bounds of the disturbances.In addition,our controllerexhibits significant simplicity,without parameter identification,disturbance estimation,function approximation,derivativecalculation,dynamic surfaces,or command filtering.Twosimulation examples are conducted to substantiate the efficacyand advantages of our approach.
基金supported by the National Natural Science Foundation of China(No.62306281)the Natural Science Foundation of Zhejiang Province(Nos.LQ23E060006 and LTGG24E050005)the Key Research Plan of Jiaxing City(No.2024BZ20016).
文摘In the era of big data,data-driven technologies are increasingly leveraged by industry to facilitate autonomous learning and intelligent decision-making.However,the challenge of“small samples in big data”emerges when datasets lack the comprehensive information necessary for addressing complex scenarios,which hampers adaptability.Thus,enhancing data completeness is essential.Knowledge-guided virtual sample generation transforms domain knowledge into extensive virtual datasets,thereby reducing dependence on limited real samples and enabling zero-sample fault diagnosis.This study used building air conditioning systems as a case study.We innovatively used the large language model(LLM)to acquire domain knowledge for sample generation,significantly lowering knowledge acquisition costs and establishing a generalized framework for knowledge acquisition in engineering applications.This acquired knowledge guided the design of diffusion boundaries in mega-trend diffusion(MTD),while the Monte Carlo method was used to sample within the diffusion function to create information-rich virtual samples.Additionally,a noise-adding technique was introduced to enhance the information entropy of these samples,thereby improving the robustness of neural networks trained with them.Experimental results showed that training the diagnostic model exclusively with virtual samples achieved an accuracy of 72.80%,significantly surpassing traditional small-sample supervised learning in terms of generalization.This underscores the quality and completeness of the generated virtual samples.
文摘With the rapid integration of renewable energy sources,modern power systems are increasingly challenged by heightened volatility and uncertainty.Doubly-fed variable-speed pumped storage units(DFVS-PSUs)have emerged as promising technologies for mitigating grid oscillations and enhancing system flexibility.However,the excitation converters in DFVS-PSUs are prone to significant issues such as elevated common-mode voltage(CMV)and neutral-point voltage(NPV)fluctuations,which can lead to electromagnetic interference and degrade transient performance.To address these challenges,an optimized virtual space vector pulse width modulation(OVSVPWM)strategy is proposed,aiming to suppress CMV and NPV simultaneously through coordinated multi-objective control.Specifically,a dynamic feedback mechanism is introduced to adjust the balancing factor of basic vectors in the synthesized virtual small vector in real-time,achieving autonomous balancing of the NPV.To address the excessive switching actions introduced by the OVSVPWM strategy,a phase duty ratio-based sequence reconstruction method is adopted,which reduces the total number of switching actions to half of the original.A zero-level buffering scheme is employed to reconstruct the single-phase voltage-level output sequence,achieving peak CMV suppression down to udc/6.Simulation results demonstrate that the proposed strategy significantly improves electromagnetic compatibility and operational stability while maintaining high power quality.
基金financially supported by the Talent Initiation Fund of Wuxi University(550220008).
文摘With the increasing integration of renewable energy,microgrids are increasingly facing stability challenges,primarily due to the lack of inherent inertia in inverter-dominated systems,which is traditionally provided by synchronous generators.To address this critical issue,Virtual Synchronous Generator(VSG)technology has emerged as a highly promising solution by emulating the inertia and damping characteristics of conventional synchronous generators.To enhance the operational efficiency of virtual synchronous generators(VSGs),this study employs smallsignal modeling analysis,root locus methods,and synchronous generator power-angle characteristic analysis to comprehensively evaluate how virtual inertia and damping coefficients affect frequency stability and power output during transient processes.Based on these analyses,an adaptive control strategy is proposed:increasing the virtual inertia when the rotor angular velocity undergoes rapid changes,while strengthening the damping coefficient when the speed deviation exceeds a certain threshold to suppress angular velocity oscillations.To validate the effectiveness of the proposed method,a grid-connected VSG simulation platform was developed inMATLAB/Simulink.Comparative simulations demonstrate that the proposed adaptive control strategy outperforms conventional VSGmethods by significantly reducing grid frequency deviations and shortening active power response time during active power command changes and load disturbances.This approach enhances microgrid stability and dynamic performance,confirming its viability for renewable-dominant power systems.Future work should focus on experimental validation and real-world parameter optimization,while further exploring the strategy’s effectiveness in improvingVSG low-voltage ride-through(LVRT)capability and power-sharing applications in multi-parallel configurations.
文摘Background:Submarine personnel often experience insomnia and reduced psychological resilience due to extended deployments in confined,high-stress environments.Effective non-pharmacological interventions are needed to improve sleep quality and resilience in this population.This study aimed to investigate the effect of virtual reality(VR)combined with forest therapy interventions on psychological resilience and sleep quality among submarine personnel with insomnia symptoms.Methods:Using convenience sampling,92 submarine personnel with insomnia symptoms undergoing recuperation at a PLA sanatorium between July 2023 and May 2025 were randomly allocated to experimental and control groups(n=46 each).The control group received forest therapy intervention,while the intervention group received combined VR and forest therapy interventions.Pre-and post-intervention assessments were conducted using the Pittsburgh Sleep Quality Index(PSQI)and Connor-Davidson Resilience Scale(CD-RISC).Results:There is no significant differences between two groups before the intervention on sleep or psychological resilience.Both groups showed significant pre-to post-intervention improvements in sleep and resilience;however,mixed-ANOVA results showed that the intervention(VR+forest therapy)group achieved significantly better outcomes than the control group at post-intervention after Bonferroni correction,including lower PSQI total and key component scores(subjective sleep quality,sleep efficiency,daytime dysfunction)and higher CD-RISC resilience scores.Conclusions:The integration of virtual reality and forest therapy effectively improved sleep quality and psychological resilience among submarine personnel with insomnia symptoms.This combined intervention shows promise as a non-pharmacological approach in military healthcare settings;however,further studies are needed to validate and generalize these findings.
基金supported by a project supported by Scientific Research Fund of Zhejiang Provincial Education Department(Grant number Y202457058).
文摘Objectives This scoping review aimed to identify and summarize the current research on virtual reality(VR)technologies used for health education in cancer patients,as well as to identify key areas of application.Methods In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines,a comprehensive literature search was performed across 11 electronic databases and gray literature sources from inception to 12 September 2025.Studies employing immersive VR tools to improve health education outcomes in cancer patients were included.Data extraction and thematic synthesis were conducted to map evidence regarding VR modalities,educational applications,and outcome measures.Results Twenty-eight studies met the inclusion criteria.VR was applied across four primary educational scenarios,including radiotherapy,chemotherapy,surgery,and healthy behavior(including rehabilitation,smoking cessation,and self-management).Eight distinct VR modalities were identified,namely VR videos,virtual environments,virtual environment for radiotherapy training(VERT),VR interactions,3D models,VR games,VR non-player characters(VR NPCs),and virtual libraries.Among these,VR videos(50.0%),virtual environments(46.4%),and VR interactions(28.6%)were the most frequently employed.The interventions led to significant improvements in patient knowledge,skills,attitudes,health behaviors,and psychological well-being.A clear evolution in VR educational approaches has been observed,shifting from static environmental familiarization toward interactive,gamified,and intelligence-driven experiences.Nevertheless,notable gaps remain regarding safety protocols and data privacy protections,with only a minority of studies addressing these issues.Conclusions VR technologies demonstrate considerable promise as an innovative educational tool in oncology care,enhancing patient understanding,psychological preparedness,and engagement throughout the cancer journey.Future implementation must address infrastructural,ethical,and user-centered design barriers to facilitate the scalable and sustainable integration of this approach into clinical practice.
基金supported by the National Natural Science Foundation of China(Nos.12175321,W2443004,11975021,11675275,U1932101)Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA10010900)+2 种基金National Key Research and Development Program of China(Nos.2023YFA1606000 and 2020YFA0406400)National College Students Science and Technology Innovation ProjectUndergraduate Base Scientific Research Project of Sun Yat-sen University。
文摘Detector and event visualization are crucial components of high-energy physics(HEP)experimental software.Virtual reality(VR)technologies and multimedia development platforms,such as Unity,offer enhanced display effects and flexible extensibility for visualization in HEP experiments.In this study,we present a VR-based method for detector and event displays in the Jiangmen Underground Neutrino Observatory(JUNO)experiment.This method shares the same detector geometry descriptions and event data model as those in the offline software and provides the necessary data conversion interfaces.The VR methodology facilitates an immersive exploration of the virtual environment in JUNO,enabling users to investigate the detector geometry,visualize event data,and tune the detector simulation and event reconstruction algorithms.Additionally,this approach supports applications in data monitoring,physics data analysis,and public outreach initiatives.
基金supported by Nursing and Midwifery Practice Development Unit(NMPDU),Dublin South,Kildare,and Wicklow,Nurses preparedness for end of life conversations(No.P210537)。
文摘Objective:Nurse-led virtual outpatient clinics are now a familiar component of healthcare delivery across many disciplines,including cancer care,or thopedics,rheumatology,and gastroenterology.However,establishing a nurse-led vir tual clinic is challenging for nursing management,par ticularly regarding resources.We aimed to investigate nursing practices and processes and patient experiences in relation to vir tual outpatient clinics.Methods:This was a cross-sectional,descriptive study using mixed data collection methods.Patients(n=324)from 4 specialist clinics completed the Virtual Clinics Patient Satisfaction Questionnaire(VCSQ)survey.Five Nurse Specialists participated in a focus group interview.Results:Most participants(86.3%)reported being satisfied/very satisfied with the virtual clinics,particularly those that were nurse-led.Nurse specialists identified electronic health records(EHRs)and additional IT and administrative support as important for efficiency and effectiveness of the clinics.Conclusions:Nurse-led virtual clinics can be an effective and efficient way to provide care to patients.Nurse managers need to ensure supportive structures are in place,for example,dedicated administrators,IT support and infrastructure,education/training,and relevant policies/procedures.The success of nurse-led virtual services requires key infrastructure to support nursing staff and sustain this service.
基金funded by the Department of Education of Liaoning Province and was supported by the Basic Scientific Research Project of the Department of Education of Liaoning Province(Grant No.LJ222411632051)and(Grant No.LJKQZ2021085)Natural Science Foundation Project of Liaoning Province(Grant No.2022-BS-222).
文摘Virtual power plant(VPP)integrates a variety of distributed renewable energy and energy storage to participate in electricity market transactions,promote the consumption of renewable energy,and improve economic efficiency.In this paper,aiming at the uncertainty of distributed wind power and photovoltaic output,considering the coupling relationship between power,carbon trading,and green cardmarket,the optimal operationmodel and bidding scheme of VPP in spot market,carbon trading market,and green card market are established.On this basis,through the Shapley value and independent risk contribution theory in cooperative game theory,the quantitative analysis of the total income and risk contribution of various distributed resources in the virtual power plant is realized.Moreover,the scheduling strategies of virtual power plants under different risk preferences are systematically compared,and the feasibility and accuracy of the combination of Shapley value and independent risk contribution theory in ensuring fair income distribution and reasonable risk assessment are emphasized.A comprehensive solution for virtual power plants in the multi-market environment is constructed,which integrates operation strategy,income distribution mechanism,and risk control system into a unified analysis framework.Through the simulation of multi-scenario examples,the CPLEXsolver inMATLAB software is used to optimize themodel.The proposed joint optimization scheme can increase the profit of VPP participating in carbon trading and green certificate market by 29%.The total revenue of distributed resources managed by VPP is 9%higher than that of individual participation.
基金funding support from the National Science and Technology Council(NSTC),under Grant No.114-2410-H-011-026-MY3.
文摘Small datasets are often challenging due to their limited sample size.This research introduces a novel solution to these problems:average linkage virtual sample generation(ALVSG).ALVSG leverages the underlying data structure to create virtual samples,which can be used to augment the original dataset.The ALVSG process consists of two steps.First,an average-linkage clustering technique is applied to the dataset to create a dendrogram.The dendrogram represents the hierarchical structure of the dataset,with each merging operation regarded as a linkage.Next,the linkages are combined into an average-based dataset,which serves as a new representation of the dataset.The second step in the ALVSG process involves generating virtual samples using the average-based dataset.The research project generates a set of 100 virtual samples by uniformly distributing them within the provided boundary.These virtual samples are then added to the original dataset,creating a more extensive dataset with improved generalization performance.The efficacy of the ALVSG approach is validated through resampling experiments and t-tests conducted on two small real-world datasets.The experiments are conducted on three forecasting models:the support vector machine for regression(SVR),the deep learning model(DL),and XGBoost.The results show that the ALVSG approach outperforms the baseline methods in terms of mean square error(MSE),root mean square error(RMSE),and mean absolute error(MAE).
文摘Researchers are increasingly focused on enabling groups of multiple unmanned vehicles to operate cohesively in complex,real-world environments,where coordinated formation control and obstacle avoidance are essential for executing sophisticated collective tasks.This paper presents a Distributed Formation Control and Obstacle Avoidance(DFCOA)framework for multi-unmanned ground vehicles(UGV).DFCOA integrates a virtual leader structure for global guidance,an improved A^(*)path planning algorithm with an advanced cost function for efficient path planning,and a repulsive-force-based improved vector field histogram star(VFH^(*))technique for collision avoidance.The virtual leader generates a reference trajectory while enabling distributed execution;the improved A^(*)algorithm reduces planning time and number of nodes to determine the shortest path from the starting position to the goal;and the improved VFH^(*)uses 2D LiDAR data with inter-agent repulsive force to simultaneously avoid collision with obstacles and maintain safe inter-vehicle distances.The formation stability of the proposed DFCOA reaches 95.8%and 94.6%in two scenarios,with root mean square(RMS)centroid errors of 0.9516 and 1.0008 m,respectively.Velocity tracking is precise(velocity centroid error RMS of 0.2699 and 0.1700 m/s),and linear velocities closely match the desired 0.3 m/s.Safety metrics showed average collision risks of 0.7773 and 0.5143,with minimum inter-vehicle distances of 0.4702 and 0.8763 m,confirming collision-free navigation of four UGVs.DFCOA outperforms conventional methods in formation stability,path efficiency,and scalability,proving its suitability for decentralized multi-UGV applications.
