A parallel robotic attachment and its remote manipulation

This paper discusses a 3-dof (degree of freedom) parallel robotic attachment and its remote manipulation. This attachment is designed as a tripod that provides two rotary motions and one linear motion. The attachment can be mounted onto a variety of machines for different applications, including CNC milling machines, industrial robots, and CMM. Java technologies are used to develop a remote manipulation system for the parallel robotic attachment, including remote monitoring and control. The main difference of this system from the existing web-based or internet-based remote systems is the way to control the motion of the machine from a remote site. Instead of using a camera for monitoring, the tripod is modeled using 3D computer graphics with behavioral control nodes embedded. Compared with camera-based solutions, network traffic is largely reduced, thereby making real-time remote device manipulation practical on the web. Our parallel robotic attachment is one type of parallel kinematic mechanisms (PKM). With PKM emerging as a new way of building flexible systems or agile machines, its advantage over serial mechanism is also presented.     

Web-based three-dimensional geo-referenced visualization

This paper addresses several approaches to implementing web-based, three-dimensional (3-D), geo-referenced visualization. The discussion focuses on the relationship between multi-dimensional data sets and applications, as well as the thick/thin client and heavy/light server structure. Two models of data sets are addressed in this paper. One is the use of traditional 3-D data format such as 3-D Studio Max, Open Inventor 2.0, Vis5D and OBJ. The other is modelled by a web-based language such as VRML. Also, traditional languages such as C and C++, as well as web-based programming tools such as Java, Java3D and ActiveX, can be used for developing applications. The strengths and weaknesses of each approach are elaborated. Four practical solutions for using VRML and Java, Java and Java3D, VRML and ActiveX and Java wrapper classes (Java and C/C++), to develop applications are presented for web-based, real-time interactive and explorative visualization.     

基于嵌入式Web的发射机远程监控系统

为了保证广播电视节目的安全稳定播出,需要对广播电视发射机运行状态进行远程监测和控制。基于Web的广播电视发射机远程监控具有很强的适应性和开放性,符合现代远程监控系统的要求。讨论了基于Web服务器的广播电视发射机远程监控的2种方案,给出了基于嵌入式Web的广播电视发射机远程监控系统体系结构和系统功能,介绍了以SX52BD微处理器为核心的嵌入式Web服务器的软硬件设计与实现。针对系统功能的要求,着重对软件设计进行了分析,并提出利用Java Applet和Socket技术在Web页面上实现监控计算机与嵌入式Web服务器进行动态交互的具体方法。系统应用于某电视发射台发射机的远程监控,试运行效果良好。     

A Constraint-Based Robotic Soccer Team

It is a challenging task for a team of multiple fast-moving robots to cooperate with each other and to compete with another team in a dynamic, real-time environment. For a robot team to play soccer successfully, various technologies have to be incorporated including robotic architecture, multi-agent collaboration and real-time reasoning. A robot is an integrated system, with a controller embedded in its plant. A robotic system is the coupling of a robot to its environment. Robotic systems are, in general, hybrid dynamic systems, consisting of continuous, discrete and event-driven components. Constraint Nets (CN) provide a semantic model for modeling hybrid dynamic systems. Controllers are embedded constraint solvers that solve constraints in real-time. A controller for our robot soccer team, UBC Dynamo98, has been modeled in CN, and implemented in Java, using the Java Beans architecture. A coach program using an evolutionary algorithm has also been designed and implemented to adjust the weights of the constraints and other parameters in the controller. The results demonstrate that the formal CN approach is a practical tool for designing and implementing controllers for robots in multi-agent real-time environments. They also demonstrate the effectiveness of applying the evolutionary algorithm to the CN-modeled controllers.     

分布式同步协同包装纸盒CAD/CAM系统的设计与实现

采用Java技术开发了基于Web的分布式同步协同包装纸盒CAD／CAM系统．研究了纸盒CAD／CAM系统的体系结构、系统功能的分配、分布式同步协同设计、并发控制、协同感知、负载均衡、3D可视化技术、参数化设计以及系统安全性的保证等关键技术．     

Java3D在钢结构建模中的应用

Java3D是基于Java平台的、功能强大的面向对象的三维图形应用程序接口(API)，它的设计是对目前流行的诸如OpenGL和Direct3D的3D图形API的重大革新。利用Java3D能使三维建模变得更加快捷和清晰。该文就如何应用Java3D建立三维钢结构模型进行了初步的探讨。     

Web-based learning in the computer-aided design curriculum

Abstract This study attempts to apply the principle of constructivism and virtual reality (VR) technologies to computer-aided design (CAD) curriculum by integrating network, CAD and VR into a web-based learning environment. Through VR technologies, it is expected that the traditional two-dimensional (2D) computer graphics course can be expanded into a three-dimensional (3D) real-time simulation one. VR technologies provide a novel method to enhance user visualisation of complex three-dimensional graphics and environments. Experience and environmental interaction allow users more readily to perceive the dimensional interrelations of graphics which are typically portrayed through static multiview or pictorial representations. A web-based learning system ( WebDeGrator ) has been developed to simulate a computer graphics learning system for learning. Future developments of the proposed web-based learning framework are also discussed.     

EJS+EjsRL: An interactive tool for industrial robots simulation, Computer Vision and remote operation

This paper presents an interactive Java software platform which enables users to easily create advanced robotic applications together with Computer Vision processing. This novel tool is composed of two layers: (1) Easy Java Simulations (EJS), an open-source tool which provides support for creating applications with a full 2D/3D interactive graphical interface, and (2) EjsRL, a high-level Java library specifically designed for EJS which provides a complete functional framework for modeling and simulation of arbitrary serial-link manipulators, Computer Vision algorithms and remote operation. The combination of both components sets up a software architecture which contains a high number of functionalities in the same platform to develop complex simulations in Robotics and Computer Vision fields. In addition, the paper shows its successful application to virtual and remote laboratories, web-based resources that enhance the accessibility of experimental setups for education and research.     

Jabiru: harnessing Java 3D behaviors for device and display portability

The aim of this paper is to use the Java 3D ConfiguredUniverse utilities to create a set of behaviors that we can integrate into existing Java 3D programs, as long as these programs use the ConfiguredUniverse. We call this behavior package Jabiru (Java 3D Application Behavior Immersive Virtual Reality Utilities). The Jabiru set of behaviors, accessible from a master menu, facilitates moving Java 3D applications originally created for desktop environments to immersive VR environments and vice versa. Jabiru also provides a six-degrees-of-freedom (6DOF) device emulator for a conventional mouse, meant to facilitate offsite testing of immersive VR behaviors on a desktop. The main focus of our work with a CAVE is in relation to bioinformatics, which has embraced Java and Java 3D as one of the choice programming environments. By creating this package, we help bring 3D graphics to both the bioinformatics community and the casual Java 3D developer or user. We discuss the design and implementation of Jabiru.     

设计艺术学视野中的中国古代三足器研究

三足器,在本文中是指鬶、鼎、爵等以三足为造型特征的器物,这些器物曾经在中国古代文化中扮演过特殊的角色。文章把这种造型特殊的器型看作一个整体的类型——三足器,试图通过三足器的历史演化来解读它独特的文化身份并探寻中国古代的设计思想。     

基于SNMP的嵌入式系统Web管理模型

提出了嵌入式系统的一个远程Web管理模型，该模型以Web浏览器和服务器(Browser-Server)为框架，基于简单网络管理协议SNMP(Simple Network Management Protocol)管理器一代理(Manager—Agent)管理方式，利用平台独立且有丰富GUI接口的Java技术进行监控和表现。它使嵌入式系统管理员可以在任何时间和任何地点通过友好的、平台无关的GUI接口对嵌入式系统进行远程监控。最后对模型中主要组件的体系结构分别进行了设计。     

Seamless Integration of Databases in VR for Constructing Virtual Environments

An approach for authoring virtual environments within the virtual environments themselves is presented, integrating a database containing arbitrary components that are used to construct the 3D scene. The issues important to a seamless integration of the database, such as multimedia data storage and database linkage are discussed, with the focus on the human-computer interaction component. A concept for a 3D database interface is described for query, presentation and usage of query results in the virtual environment. Finally, an implementation of the concept using VRML and Java is presented.     

嵌入式Java的Mobile 3D实现

嵌入式领域移动3D图形技术的出现与发展是人们对高性能娱乐、时尚、商务不断追求的必然结果。该文依据J2ME的移动3D图形规范（JSR-184）,实现了基于嵌入式Java的Mobile 3D。分析了JSR-184规范及相对应的渲染流水线,提出实现架构和方案。对移动3D图形的前景做出了展望。     

嵌入式Java编译器的研究与设计

提出用编译的方法设计一款能直接生成 MCS-51系列单片机的目标代码,不依赖操作系统和JVM的嵌入式Ja-va编译器,使得Java语言在低档嵌入式系统中应用更加广泛,实现成本低廉的工业环境及家庭电器与 Internet 相结合实现远程监测和控制.详细分析了Java语言与嵌入式系统的特点,以实时版jRate及 sun公司的GJC编译系统为参考,采用单遍扫描语法制导翻译模式,以语法分析程序单元为核心,构建嵌入式Java 编译器的词法分析器、语法/语义分析器和代码生成器,并对测试方法进行了探讨.     

基于Java的嵌入式软件在电子设备中的应用研究

编写的目的在于探讨Java是否能用于嵌入式系统,因为Java本身的跨平台性具有很大的优点。首先,介绍了Java,探讨了它的优、缺点,然后,着重研究了Java在嵌入式电子设备中的应用。最后,还为Java在嵌入式环境下提供了一个实施模型。此模型充分利用了Java的优点,完整保持了设备的高度可靠性和重要的传输特性。结论是：如果实施正确,Java对嵌入式设备来说是很有意义的。     

The Java 3D API and virtual reality

Java programmers can quickly and easily define graphics programs using Java 3D's scene graph classes. An expanded view model lets applications seamlessly operate in a variety of single- and multiple-display, nonhead-tracked and head-tracked, display environments. This view model relies on the flexible InputDevice interface that Java 3D provides to remove most of the vagaries of hardware trackers     

iJob: an Internet-based job execution environment using asynchronous messaging

Various toolkits exist today for the distributed execution of computational algorithms on clusters of machines. These toolkits are often referred to by the terms ‘Grid Toolkits’, ‘Job Execution Environments’, and ‘Problem Solving Environments (PSEs)’. Here, we introduce iJob—an Internet-based job execution environment that sets out to meet many of the goals of PSEs, such as providing facilities and services to solve a class of problems. In addition, the iJob software allows execution of computational algorithms utilizing standard Internet technologies such as Java, XML, and asynchronous communication protocols. The goals of this project include: (1) deploying the toolkit easily to multiple platforms using the Java technologies; (2) running multiple types of algorithms and supporting multiple users simultaneously; (3) providing a web-based GUI for monitoring and controlling the status of jobs; and (4) providing security at both the user-level and at the network-level. The toolkit has been tested using several simulation codes on pools of Windows 2000 and Solaris systems.     

SVG数字高程模型生成与3D可视化方法

可缩放矢量图形(SVG)不支持3D模型的建立,为此,介绍SVG扩展元素的实现原理,研究在SVG的3D模型建立方法,利用三角网格差分方法解决元素不支持点数不一致、非均匀对象分布的问题,在SVG中建立3D数字高程模型,并对其实现在线旋转控制。对内嵌JS和Java后台程序生成DEM的方案进行比较,结果表明,内嵌JS方案的时间消耗较大,有必要扩展SVG标准中的3D表示标签。     

基于Java 3D的生物大分子模拟可视化系统

本文采用基于Java 3D的三维可视化编程环境,利用Java 3D、Java Applet、Java多线程等技术,开发了一个适于网络环境的生物大分子模拟的可视化系统,有效地解决了网络环境下生物大分子模拟计算中的三维图像的动静态显示、用户交互、进程控制等问题。