基于VR技术的防震安全教育软件的设计与实现

本文分析了虚拟现实技术应用于防震安全教育的优势,设计了虚拟场景的开发方案,利用3DS MAX,Virtools等软件工具设计开发出了防震安全教育软件。为了验证虚拟现实技术在防震安全教育中的有效应用,还对该软件作了测试与评价。     

Modeling and real-time simulation architectures for virtual prototyping of off-road vehicles

Virtual Reality-based simulation technology has evolved as a useful design and analysis tool at an early stage in the design for evaluating performance of human-operated agricultural and construction machinery. Detecting anomalies in the design prior to building physical prototypes and expensive testing leads to significant cost savings. The efficacy of such simulation technology depends on how realistically the simulation mimics the real-life operation of the machinery. It is therefore necessary to achieve ‘real-time’ dynamic simulation of such machines with operator-in-the-loop functionality. Such simulation often leads to intensive computational burdens. A distributed architecture was developed for off-road vehicle dynamic models and 3D graphics visualization to distribute the overall computational load of the system across multiple computational platforms. Multi-rate model simulation was also used to simulate various system dynamics with different integration time steps, so that the computational power can be distributed more intelligently. This architecture consisted of three major components: a dynamic model simulator, a virtual reality simulator for 3D graphics, and an interface to the controller and input hardware devices. Several off-road vehicle dynamics models were developed with varying degrees of fidelity, as well as automatic guidance controller models and a controller area network interface to embedded controllers and user input devices. The simulation architecture reduced the computational load to an individual machine and increased the real-time simulation capability with complex off-road vehicle system models and controllers. This architecture provides an environment to test virtual prototypes of the vehicle systems in real-time and the opportunity to test the functionality of newly developed controller software and hardware.     

Teaching your system to share

Creating multi-user virtual worlds is a relatively new challenge for developers of virtual reality applications. It is especially challenging to build networked VR systems based on inexpensive PC-based hardware, due to limitations in system software and inefficient networking hardware. This article explains how we created a multi-person shared virtual environment using DOS-based PCs. It also covers some of the design goals in creating a collaborative design tool for creating and modifying virtual buildings. Workroom is a general purpose simulation infrastructure that allows multiple participants to interact in unpredictable ways while minimizing simulation latency     

Adapting Virtual Reality for the Participatory Design of Work Environments

This paper describes the evolution of a standard PC-based virtual reality tool which has been adapted for the participatory design of work environments. Tool features, method of control and combination with other participatory design tools are investigated in the context of a particular design situation. This research is aimed at participatory design facilitators to aid in the adaptation of similar virtual reality systems for a similar purpose. The context of this work is the Envisionment Workshop, in which a group of workers participate with design experts in using full-scale modelling, pedagogical drama, and democratic meetings to (re)design their workplace. A series of prototypes have been developed and tested during the design of a new university in the region using a case study methodology to provide high ecological validity. These were preceded by a task analysis, brainstorming and pilot study. The results suggest that such a tool can be constructed and used successfully by a small group of people using projected virtual reality. However larger groups suffer from a bottleneck at the input devices such that a virtual reality expert must take control and build what the participants wish. This revised version was published online in August 2006 with corrections to the Cover Date.     

基于虚拟现实的水处理车间仿真的研究

为了达到在工人上岗前对其工作流程进行培训的目的,利用三维建模工具3DSMAX和虚拟现实仿真软件Cult 3D进行水处理车间工作流程的模拟.该文详细介绍了虚拟现实技术Cult 3D的功能,并将虚拟现实技术应用于大庆第二采油厂的水处理车间,详细分析了建模过程需要注意的问题以及如何模拟水处理车间工人操作的流程,同时分析了编程过程中的关键技术,开发了三维仿真动画程序.程序可以自动生成水处理车间的三维模型,并且以三维交互动画的形式演示操作流程.     

基于GPSS／H和GKS的FMS物流系统的动画仿真

本文介绍了在ｓｕｎ－３工作站上实现的ＦＭＳ动画仿真系统。该系统在开发Ｓｕｎ－３的ＧＰＳＳ／Ｈ及Ｓｕｎ ＧＫＳ软件的基础上，用Ｃ语言编制全部软件，具有良好的人机接口。利用该系统实现ＦＭＳ的动画仿真，具有易于建模和调试，开发周期短，符合标准化，易于验证正确性和可靠性等特点，为开发研制ＦＭＳ提供了有效的手段。这里着重介绍ＦＭＳ物流系统仿真的建模方法，软件设计以及仿真程序与动画程序的软件接口等。     

Dynamic virtual environment to test teleoperated systems with time delay communications

This paper presents a dynamic virtual environment tool for training operators and to prove different control schemes in telerobotic systems, and describes virtual reality environments used in teleoperated robotic systems. In the presented tool, the kinematic and dynamic model of the remote environment which is manipulating the operator is considered. The paper also describes how time delays in the communication channel can be easily added to the simulator, in order to analyze their effects in the teleoperated system. Finally, some experimental results achieved with this virtual teleoperated system are shown. With the presented dynamic simulator, different control schemes designed to overcome the time delay problem could be tested. © 2005 Wiley Periodicals, Inc.     

Modelling flexible manufacturing systems using mean-value analysis

Flexible manufacturing systems (FMS) represent an important new development in automated manufacturing of parts with mid-volume demand. In the design and operation of these complex systems, it is useful to have tools that predict their performance under various conditions. This paper describes one such tool called MVAQ, a computer program based on mean-value analysis of queues. Part production rates, machine utilization and average work-in-process sizes are all easily obtained using MVAQ. The reader is advised on when MVAQ should be used for modelling FMSs and how the program can be used. A simple design example is given to illustrate the use of MVAQ. A brief tutorial on the theory behind MVAQ is also included.     

嵌入式组态软件脚本解释虚拟机的设计

为了增强嵌入式组态软件的功能,引入一种类似于C语言的脚本.设计一个编译器把该脚本编译成中间代码,采用中间代码的优点是可提高程序运行的速度,也减小了脚本解释程序的设计难度.提出一种仿微处理器结构的脚本虚拟机设计方案,在运行时对中间代码进行解释.虚拟机主要由程序存储器、指令译码器、运算器、程序计数器、控制器以及动态容器组成,其中动态容器的设计是关键,它具有可动态分配内存、自动释放内存等优点,适合于嵌入式操作系统下运行.实验与测试结果表明,该脚本解释虚拟机可满足嵌入式组态软件设计的要求.     

iCoSim-FMS: An intelligent co-simulator for the adaptive control of complex flexible manufacturing systems

We describe an intelligent co-simulator for real time production control of a complex flexible manufacturing system (CFMS) having machine and tool flexibility. The manufacturing processes associated with the CFMS are complicated with each operation being possibly done by several machining centers. The co-simulator design approach is built upon the theory of dynamic meta-model based supervisory control with the cooperation of its own embedded intelligent blocks. The system is implemented by coupling of the centralized simulation controller (CSC) and real-time simulator for enforcing dynamic strategies of shop floor control. The posteriori adaptive co-simulator is equipped with a concurrent bilateral mechanism for simulation optimization based on appropriate control rules enhancing performance criteria simulation efficiency. A working intelligent adaptive controller prototype (iCoSim-FMS) has been developed to validate the proposed approach and compare its performance with well known FMS heuristic methods.     

Virtual reality and its role in removing the barriers that turn cognitive impairments into intellectual disability

Early expectations of the contribution that virtual reality (VR) could make to education far exceeded actual applications. This was largely due to the initial immaturity of the technology and a lack of evidence base on which to base design and utilisation. While the early developments in computer based learning largely concentrated on mainstream education, leaving those with special needs behind, the potential of VR as an educational tool was exploited for those with intellectual disabilities right from the start. This paper describes the empirical evidence that has contributed to the development of educational virtual reality for those with intellectual disabilities: studies on transfer of learning from the virtual to the real world; how teachers might support those using VR; the design of virtual environments and what input/control devices best facilitate use of desktop VR. Future developments and ethical issues are also considered.     

Dynamic Performance of Mobile Haptic Interfaces

The increasing demand for virtual reality applications in several scientific disciplines feeds new research perspectives dealing with robotics, automation, and computer science. In this context, one of the topics is the design of advanced force-feedback devices allowing not only kinesthetic interaction with virtual objects but also locomotion and navigation inside virtual worlds. This has the main advantage to stimulate human vestibular apparatus, thus increasing the overall realism of simulation. Particularly, this paper deals with mobile haptic interfaces (MHIs), built by combining standard force-feedback devices with mobile platforms. We investigated which factors may affect the transparency of this kind of devices, identifying in mobile robot dynamics a possible cause of loss of transparency. Hence, in this paper, we present a method to analyze dynamic performance of an MHI and some basic guidelines to design controller in order to meet desired specifications. Experimental validation of the theoretical results is reported.     

FMS中动画仿真系统的设计与实现

ＦＭＳ动画仿真系统是通用单元控制器中的一个主要子系统，本文介绍了该系统的两个主要组成；     

A Sensorized Garment Controlled Virtual Robotic Wheelchair

This paper presents the design and performance of a body-machine-interface (BoMI) system, where a user controls a robotic 3D virtual wheelchair with the signals derived from his/her shoulder and elbow movements. BoMI promotes the perspective that system users should no longer be operators of the engineering design but should be an embedded part of the functional design. This BoMI system has real-time controllability of robotic devices based on user-specific dynamic body response signatures in high-density 52-channel sensor shirt. The BoMI system not only gives access to the user’s body signals, but also translates these signals from user’s body to the virtual reality device-control space. We have explored the efficiency of this BoMI system in a semi-cylinderic 3D virtual reality system. Experimental studies are conducted to demonstrate, how this transformation of human body signals of multiple degrees of freedom, controls a robotic wheelchair navigation task in a 3D virtual reality environment. We have also presented how machine learning can enhance the interface to adapt towards the degree of freedoms of human body by correcting the errors performed by the user.     

集成虚拟现实环境在工程设计分析中的应用 *

虚拟现实技术在工程设计与分析上有很大的应用潜力。可是 ,虚拟环境的创建时间长、成本高,极大地限制了虚拟现实技术在工程上的应用。为此 ,提出了虚拟现实脚本生成器的概念,将虚拟现实技术与过程的设计、分析集成化,创造性地提出了一种自上而下的设计方法———VR-IEDA,以便高效、快速地创建虚拟原型,提高计算机虚拟复杂系统工程的性价比。在 VR-IEDA中复杂系统的结构和行为被计算机捕捉并自动生成可执行的 VR仿真代码 ,从而减少了创建虚拟环境的时间,便利了基于仿真的过程分析和设计。最后 ,以武器系统的维修过程为     

MATLAB在虚拟现实技术中的应用

本文在简要介绍MATLAB和Simulink的基础上,结合其虚拟现实工具箱,重点分析MATLAB在虚拟现实中的应用,同时展示了在MAILAB和Simulink中创建和处理三维模型的过程和接口应用。最后结合飞机模型的应用实例,验证了MATLAB在虚拟现实技术中应用的可行性。     

虚拟现实在室内设计中的研究

主要探讨了选择虚拟现实系统,建立虚拟现实环境以及虚拟现实系统在实际应用,同时阐述了虚拟现实在未来室内设计的发展趋势。通过该系统让用户仿佛置身于这个设计的虚拟场景中,感受身临其境的效果。     

基于VAPS的FMS CDU 实时仿真系统开发

基于VAPS建立了飞行管理系统控制显示组件（CDU）实时仿真系统。在满足真实性和可靠性的前提下,给出了基于VAPS的CDU设计方法。建立了一个通用的、基于网络连接的飞行管理系统的CDU模型。在满足实时性要求的前提下,实现了飞机管理系统中控制显示组件的动态图形仿真以及在实时环境中飞行计划的生成。对飞行计划的生成进行了讨论,解决了仿真中的一些关键技术,并实现了在实时运行环境中的故障处理、数据传输及通信功能。为达到一个完整的FMS仿真系统打下了基础。     

Haptic Direct-Drive Robot Control Scheme in Virtual Reality

This paper explores the use of a 2-D (Direct-Drive Arm) manipulator for mechanism design applications based on virtual reality (VR). This article reviews the system include a user interface, a simulator, and a robot control scheme. The user interface is a combination of a virtual clay environment and human arm dynamics via robot effector handler. The model of the VR system is built based on a haptic interface device behavior that enables the operator to feel the actual force feedback from the virtual environment just as s/he would from the real environment. A primary stabilizing controller is used to develop a haptic interface device where realistic simulations of the dynamic interaction forces between a human operator and the simulated virtual object/mechanism are required. The stability and performance of the system are studied and analyzed based on the Nyquist stability criterion. Experiments on cutting virtual clay are used to validate the theoretical developments. It was shown that the experimental and theoretical results are in good agreement and that the designed controller is robust to constrained/unconstrained environment.