A new type haptics-based virtual environment system for assembly training of complex products

Virtual reality (VR)-based assembly training has been an interesting topic for the last decades. Generally, there are two shortcomings for nowadays virtual assembly training systems. One is that the operators cannot move around the virtual environment in a natural way as people activity in the real world: they are constrained in a fixed position or can only move in a limited space. The other is that most of the virtual assembly training systems are based on geometry constraint modeling only, which lacks haptics feedback. A new type haptics-based virtual environment system for assembly training of complex products is described in this paper. A new low-cost motion simulator is designed and integrated with the virtual environment to realize free walking by human. An automatic data integration interface is developed to transfer geometry, topology, assembly, and physics information from a computer-aided design system to a VR application, and a hierarchical constraint-based data model is rebuilt to construct the virtual assembly environment. Physics-based modeling and haptics feedback are undertaken to simulate the realistic assembly operations. The application examples and evaluation experiments demonstrate that both motion simulator and haptics have great value for training of assembly processes.     

虚拟电梯系统的开发与应用

介绍了开发虚拟电梯系统的重要意义及系统实现的功能,概述了与实际物理模型电梯比较虚拟电梯系统的优势,阐述了虚拟电梯的灵活配置及其重要作用,重点介绍了以计算机为核心的虚拟电梯系统的硬件和软件实现。虚拟电梯系统为开发电梯控制系统的关键技术及电梯维修人员的培训提供良好的应用前景。     

桌面式工程机械虚拟维修训练系统技术研究

分析了面向设计任务与面向训练任务中虚拟现实技术应用目的和要求的不同,基于维修培训任务的特点和要求,应用桌面式虚拟现实技术,设计了虚拟维修训练系统的功能模块.介绍了桌面式虚拟现实技术的交互控制原理,并阐述了拆装训练、故障诊断训练及训练考核评价3个主要功能模块的设计思路及技术实现方法.开发了某型装载机虚拟维修训练系统,验证了方法的有效性.     

G语言的硬件虚拟模型

G语言是面向虚拟仪器的开发语言，一方面要模拟真实仪器的界面和功能，另一方面要满足高级语言的语法规则。本文在仪器硬件要素模型的基础上，提出基于函数节点与容器关系模型的G语言硬件虚拟模型，同时解决其语言本身要求的语法规则抽象问题，并在自主实现的虚拟仪器开发平台LabScene中实现。     

虚拟装配中基于生理约束的虚拟手建模与抓持规划

为控制虚拟手准确合理地完成虚拟零件的抓握动作,以方便快捷地实现虚拟装配仿真,在深入分析人手的解剖结构和关节运动生理约束的基础上,提出利用层次结构并借助三维虚拟现实软件EON,建立虚拟手几何模型和实现抓持控制的方法.该方法将手指简化为三关节连杆结构,采用逆向运动学方法,针对待拾取零件的位置计算出在目标位姿下各运动关节的角度值.进而利用关节插值方法,以迭代的方式实现对手部关节链上各个关节的运动控制,仿真结果验证了上述方法的可行性与实时性.     

远程维修系统中PXI虚拟仪器数据采集研究

针对远程维修系统中数据采集的特点,提出了基于PXI虚拟仪器的数据采集方案,保证系统稳定性良好。对方案中传感器、信号调理电路以及数据采集卡等有关硬件电路进行了设计;对图像信号的采集、处理方式进行了讨论。     

A novel optimal assembly algorithm for haptic interface applications of a virtual maintenance system

A virtual maintenance system in a virtual environment can be used to simulate a real-world maintenance system. The efficiency of the simulation depends mainly on the assembly/disassembly task sequence. During simulation, path planning of mechanical parts becomes an important factor since it affects the overall efficiency of the maintenance system in terms of saving energy and time. Therefore, planners must consider the path-planning factors under constraints such as obstacles and the initial/final positions of the parts, as well as the assembly sequence such as number of gripper exchanges and direction changes. We propose a novel optimal assembly algorithm that considers the assembly sequence of mechanical parts and the path-planning factors for a virtual maintenance simulation system. The genetic algorithm is used to determine the optimal sequence of parts to minimize the numbers of gripper exchanges and direction changes, as well as find a repulsive force radius by using the potential field method to generate the shortest optimal distance for transferring each part during the assembly operation. By applying the proposed algorithm to a virtual maintenance system, users can be haptically guided to the optimized assembly solution during mechanical parts assembly operations. This paper was recommended for publication in revised form by Associate Editor Jong Hyeon Park Christiand received a B.Eng. degree in Mechanical Engineering from University of Indonesia in 2006. He then went on to receive his M.Eng. from Gyeongsang National University in 2008. He is currently a member of engineering staff at Electronics and Telecommunication Research Institute (ETRI) in Daejeon, Korea. Jungwon Yoon received the B.S. degree in precision mechanical engineering in 1998 from the Chonbuk National Univ., Korea, and the M. S. degree in the Department of Mechatronics in 2000 from Gwangju Institute of Science and Technology (GIST), Kwangju, Korea, where he received the Ph.D. in 2005. He had worked as a senior researcher in Electronics Telecommunication Research Institute (ETRI), Daejeon, Korea, and a visiting researcher at Virtual Reality Lab, the Rutgers University, U.S.A, from 2001 to 2002. In 2005, he joined the School of Mechanical & Aerospace Engineering, Gyeongsang National University, Jinju, Korea, where he is currently an assistant professor. His research interests include virtual reality haptic devices & locomotion interfaces, and rehabilitation robots.     

基于虚拟仪器的磁电机定子自动检测系统

为了满足电容充电式无触点(CDI)磁电机定子出厂性能检测的需求,提高检测精度、效率以及自动化水平,研究开发了一种磁电机定子自动检测系统。基于LabVIEW测控平台,设计并开发了检测台人机界面,实现了手动和自动控制两种模式的转换运行;对磁电机电压信号进行了采集、滤波、时频和峰值处理,同步测试出了开路峰值电压和点火提前角等指标;采用三针放电模拟火花塞点火,通过对火花电压和电流同步积分运算得出了点火能量值。该系统通过实际检测台的开发验证,能够自动同时测试出两个定子的各项性能指标,效率提高80%,测试误差不超过1%。研究结果表明,该系统具有较高的测量精度和柔性,能显著降低测试成本和工人劳动强度。     

基于OpenGL的虚拟数控车床加工仿真系统研究

在分析虚拟数控机床系统结构的基础上,以Visual C++6.0为平台,研究开发了基于OpenGL交互控制的虚拟数控车床加工仿真系统,实现了在不同转速、进给速度、NC代码等条件下数控车床切削过程的动态仿真。系统具有良好的实时性、交互性、可扩展性以及三维图形显示能力,能够有效地验证程序的正确性,有助于减少试切法检查引起的低效高耗,提高数控设备的生产效率。利用计算机图形学和虚拟现实技术对数控车床的加工过程进行模拟,可以节约成本、避免制造风险、开展数控培训。     

Virtual human modeling for interactive assembly and disassembly operation in virtual reality environment

Real operators are the initiators in assembly and disassembly activities. They participate throughout the whole process. In this sense, as an avatar of a real operator, virtual human (VH) plays an important role in virtual assembly and maintenance simulations. After detailed analysis of interactive assembly and disassembly process, the function requirements for VH are defined. Based on the defined requirements, the following works are done. First, a real-time driving model is established with a dynamic constraint applied to support personalized human model driving. Then, a driving error model is proposed for quantitatively analysis of VH’s driving error coming from the motion capture system. After that, on the basis of constraint processing method, an interactive operation modeling method for VH is presented. This method deals with interactive operation modeling in scenarios where VH manipulates the product directly, VH manipulates tools, and VH manipulates the product using tools. Finally, an assembly simulation for automobile engine connecting rod caps is implemented and a user survey is carried out. The survey result demonstrates the feasibility and validity of the proposed model and method.     

虚拟现实技术在机械产品装配中的应用

从虚拟现实技术的角度,研究分析虚拟装配的相关技术及虚拟装配系统的设计流程;结合发动机曲柄连杆机构给出虚拟装配的一般步骤;指出成功完成虚拟装配的关键在于虚拟手的操作,提出虚拟手抓取的满足条件.     

嵌入虚拟机监视器的高性能虚拟网络

由虚拟机和虚拟覆盖网相结合而构成的虚拟计算环境,在云计算和绿色计算中发挥非常重要的作用,然而,现有的虚拟计算环境在性能上难以满足高性能分布式计算的要求。设计和实现了一种高性能虚拟网络:VNET/P。基于网络第2层建立虚拟机互连模型,对一组虚拟机进行抽象,使其位于同一局域网中。与早期的用户层虚拟网络系统不同,VNET/P嵌入于可扩展、高性能的Palacios虚拟机监视器中。试验结果表明,VNET/P具有高带宽的特点,其性能接近于实际硬件的性能。     

敏捷化车间虚拟环境的研究

叙述了敏捷化 ,快速重组的制造系统的车间虚拟现实环境的研究关键问题 ,分析了把仿真技术与虚拟现实构造工具结合起来的技术 ,提出达到模型驱动和动态决策能力以及适应系统变化的主要方法。     

基于虚拟远程实验室的数字电子技术实验设计

针对传统的电工电子类实验室存在的投入高,维护费用高,易受时间、地点限制等问题,设计了虚拟远程实验室(包括浏览器端、管理端和计算端),各部分通过可拓展标记语言XML通信,浏览器端的虚拟场景操作平台采用Adobe Flex技术搭建,管理端的实验调度模块采用成熟的网络框架Python Twisted开发。用户通过虚拟场景操作平台搭建好电路并仿真时,向计算端发送虚拟场景数据,计算端接收数据后,建立Modelica模型并利用仿真环境OpenModelica进行求解,最后将求解的仿真结果反馈给用户。以数字电子技术课程中的半加器实验展示了虚拟远程实验的具体步骤和仿真结果。实验结果表明,虚拟远程实验室以学习者为中心,具有良好的交互性和拓展性,操作简便,性能可靠,有效地弥补了传统电工电子类实验室的不足。     

Hand gesture-based tangible interactions for manipulating virtual objects in a mixed reality environment

In the environment of mixed reality (MR) or augmented reality (AR), there have been several previous works dealing with user interfaces for manipulating and interacting with virtual objects aimed at improving immersive feeling and natural interaction. However, it is still considered that there must be much progress in supporting human behavior-like interactions for providing control efficiency and natural feeling in MR/AR environments. This paper proposes a tangible interaction method by combining the advantages of soft interactions such as hand gesture and MR and hard interactions such as vibro-tactile feedback. One of the main goals is to provide more natural interaction interfaces similar to the manipulation task in the real world by utilizing hand gesture-based tangible interactions. It also provides multimodal interfaces by adopting the vibro-tactile feedback and tangible interaction for the virtual object manipulation. Thus, it can make users get more immersive and natural feeling in the manipulation and interaction with virtual objects. Furthermore, it provides an alternative instruction guideline based on the analysis of the previous interaction while manipulating virtual objects, which makes it possible for the user to minimize manipulation errors during the interaction phase and the learning process, which guides the user to the right direction. We will show the effectiveness and advantage of the proposed approach by demonstrating several implementation results.     

人在回路的沉浸式虚拟装配技术研究

针对传统产品开发的序贯过程,很多问题要待到实物装配时才能充分暴露,导致零部件装配缺陷发现滞后,提出了人在回路的沉浸式虚拟装配技术。研究了人在回路的沉浸式虚拟装配环境、虚拟装配关键技术、虚拟装配应用系统,提出了人在回路的沉浸式虚拟装配原理,基于Virtools搭建出虚拟装配原型系统,并进行了工程验证。结果表明,所设计的人在回路的沉浸式虚拟装配系统具有一定的工程应用性。     

Application of the virtual machine technology in the e-VLBI mode on the quasar radiointerferometric complex

Applications of the virtual machine system based on a SUN Fire X4450 workstation with a StorageTek 2530 external disk array for data exchanges between observatories of the Quasar complex and the Correlation Processing Center of the Russian Academy of Sciences in the e-VLBI mode is described. The comparison with the similar system on real workstations demonstrated the advantage of the designed system, allowing one to speak about the possibilities of using it as a master (backup) data exchange system in the e-VLBI mode to ensure operation of the GLONASS global navigation system.     

大型射电望远镜数字孪生系统架构设计与应用

为提高大型射电望远镜的自动化管理程度、增强其运维的实时性和操控的交互性,参考数字孪生经典理论模型,提出一种以智能感知为基本处理单元的数字孪生系统实时操控模型,并对其关键技术进行了阐述.以500 m口径球面射电望远镜(中国天眼)为应用案例设计开发了中国天眼数字孪生系统,并对其中的虚拟三维模型创建、数据的智能感知以及虚拟模...     

推土机保障虚拟训练系统的设计与实现

在分析推土机结构性能特点的基础上,基于模块化的设计思想,依据系统功能需求,构建保障训练系统平台.研究了推土机保障虚拟训练平台和维修仿真的实现过程,包括虚拟样机建立、保障任务科目规划、维修知识数据库构建及交互控制方法设计等内容,结合训练应用的实际需要,开发了一种推土机保障虚拟训练系统.结果表明该系统对课程设计和教学应用有良好的指导意义和实用价值.     

基于虚拟仪器技术的液压系统网络化检测

利用LabVIEW虚拟仪器开发平台,构建了液压系统网络化检测系统,该系统实现对液压系统远程宾时数据采集、测试的控制与实时显示、数据分析与存储等功能,降低了开发成本、提高了测试精度.