Using interchangeable virtual instrument (IVI) drivers to increasetest system performance

Instrument driver technology has evolved tremendously over the last decade. Initiatives such as SCPI and VXIplug&play have simplified remote instrument programming with standardized command messages and high-level utility functions. The latest initiative is the Interchangeable Virtual Instrument (IVI) Foundation. IVI defines standards for instrument drivers that offer benefits to provide higher performance. These benefits include instrument interchangeability, instrument simulation, and instrument state-caching. Because instrument drivers are an integral part of a modern test system, IVI promises to provide developers with the tools to increase their system performance significantly. This paper reviews the technical aspects of the IVI specification and the TVI architecture and describes how IVI can help the test system developer improve performance and lower long-term software maintenance costs     

IVI comes of age: An overview of IVI specifications with current status

IVI stands for Interchangeable Virtual Instruments; the IVI Foundation was formed in 1997 and is a consortium founded to promote standard specifications for programmable test instruments. The foundation focuses on the needs of users who build high performance test systems. By building on existing industry standards, such as VXIplug&play driver concepts, the Foundation's goal is to deliver specifications that simplify interchangeability, provide better performance, and maintainable test programs. To date, only a few IVI drivers have been available. In the past year, the IVI Foundation finished a major revision of it's architecture and has released a blizzard of specifications, increasing its IVI Class specification by 80% and dramatically improving the consistency and quality of released drivers. The DoD has expressed major interest in IVI's success. With the recent successful completion of the current set of specifications, DoD is interested in becoming involved in defining the next set of Class Specifications. The NxTest Working Group lists IVI as a key technical element, and DoD has recently requested that the IVI Foundation consider Electro Optical equipment for their next set of Class Specifications; a Working Group has been formed to more clearly define this activity.     

Integrating VISA, IVI and ATEasy to migrate legacy test systems

New software technologies, such as VISA and IVI, continue to bring the industry toward greater standardization. The benefit to the integrator is reduced costs through reuse of the same hardware and software. The benefit to the customer end-user is lower costs by reducing modification and support through the life-cycle to the test station. However, while we position ourselves for the future with PXI and these software technologies, we must still provide support for VXI, GPIB, and instrument drivers that use current software technologies. Using a number of additional tools such as National Instrument's Measurement and Automation Explorer and Geotest's ATEasy, we can have the power of these tools today while waiting for wider acceptance and support of the newer VISA and IVI technologies. We are just now seeing the development of IVI drivers and the ink is still wet on the VISA specification for PXI. ATEasy provided the structure necessary to use these technologies with the current technology. This paper explores the process of implementing and integrating the system driver and instrument drivers for a PXI-based test station for the TOW2 optical sight sensor.     

建立与硬件无关通用测试程序的方法

IVI 驱动技术是当今受人推崇的软件控制新技术。文中阐述了 IVI 技术的应用,真正实现了仪器的可互换性.使得工程人员的测试程序可以应用于不同的仪器设备。文中介绍了 IVI驱动机制、使用工具、建立虚拟仪器等方面的相关问题。     

Specifying an IVI class for digital test instrumentation

This paper presents an overview of work being done by Teradyne in conjunction with the IVI Foundation to specify an IVI class for digital instrumentation. The Interchangeable Virtual Instruments (IVI) Foundation was formed in August 1997 to define standard specifications for programming common test instrument capabilities. The paper will present the major architectural aspects of digital test instrumentation and how those features can be grouped into classes for the purpose of writing an instrument independent driver. Topics discussed will include derivation of capability classes, class extensions, simulation, and range checking. Examples of how the IVI digital class would apply to the Teradyne M9-Series Digital Test Instrument will be included. Conclusions will summarize the unique attributes of digital test instrumentation, the benefits which can be achieved through standardization, and the tradeoffs associated with utilizing class extensions     

VLSTA: virtual instrument standard test architecture

Diagrammatic programming environments provide a unique challenge for the developers of test software. These cost effective environments facilitate access to technologies such as VXI, provide speedy development of highly effective user interfaces, and eliminate many of the tasks often associated with hardware integration in complex test systems. Nonetheless, difficulties can arise when designing functional and diagnostic test software in this environment. This paper introduces VISTA, a promising new architecture which allows users to elude most of the difficulties of building detailed functional and diagnostic Test Program Sets (TPSs), while taking full advantage of the benefits of diagrammatic programming environments. Here we examine an implementation of the VISTA architecture, the integration of advanced diagnostics, and the use of diagrammatic programming as a test language cross compiler     

基于LabVIEW的IVI编程

在介绍IVI类驱动程序和专用驱动程序的基础上,针对测量程序控制硬件发生变化时需要耗费大量的时间和精力重新编写程序的问题,以Fluke8840A为例,描述了利用NI公司MAX软件配置IVI仪器的Logical Names和Driver Sessions的过程、方法、步骤和注意事项,及在LabVIEW开发环境下如何利用IVI驱动设计IVI数字电压表测量程序。本文对正确地利用IVI驱动设计测试系统程序、推广利用IVI技术、节省开发时间和维护成本具有重要意义。     

自动测试系统通用性的实现技术

文章分析了与开发通用ATS密切相关的标准/规范,从软、硬件两方面讨论了ATS通用性的实现途径,包括硬件配置及接口技术、IVI技术以及面向信号方法。ATS通用性的实现可以实现被测对象的跨平台测试以及测试程序的可移植,能带来显著的军事及经济效益。     

用于虚拟仪器开发的IVI技术

介绍了IVI的规范及体系结构，描述了IVI仪器驱动器的工作过程及特点，重点讨论了开始开发IVI仪器驱动程序器的方法。     

Technology roll lessons learned on embedded avionics platforms

Open system architectures based on commercial off-the-shelf (COTS) building block components offer the ability to leverage the latest technology into fielded products while minimizing the impact to the operational flight software, typically the most costly component of an avionics development or upgrade. Our team has developed a layered hardware and software approach based on industry standard hardware and software interfaces to abstract the application (operational) software developers from the underlying technology rolls to the hardware and operating system software that naturally occur as part of the commercial marketplace, A technology roll is defined as the replacement of a current product with a subsequent generation of a product from the same product family. In this article, we describe the components and the layered architecture of our open system architecture approach. We discuss specific system, hardware, and software technology insertions that incorporate the latest available technology and how these changes have been abstracted from the application software. The article concludes by discussing lessons Learned from the use of these common components and corresponding technology rolls across various platforms     

导航计算机测试软件的架构设计

为解决多种型号被测产品、在不同测试设备上的测试软件开发的问题，尽可能地缩短开发和调试时间，并确保软件的开发质量，提出了一种针对导航计算机测试这一特定领域，以提高扩展性和重用性为目标的软件架构。该架构提供了统一的测试软件设计和开发方法，规范了软件的实现过程，为测试软件的开发提供了一致性的解决方案。采用组件化的开发方法，将具有复用价值的内容封装为组件，为测试软件开发和运行提供了共享的基础平台；提供了开放式的体系结构，规定了内部的组织结构、组件类别与职责、接口规范、交互方式、组件开发方法，便于软件的扩展和修改。经过工程项目的验证，该架构满足在各种专用测试设备上、针对不同型号被测产品的测试软件快速、高质量开发的需要。     

Sustainment of legacy automatic test systems: lessons learned on TPS transportability

Sustainment of legacy automatic test systems (ATS) saves cost through the re-use of software and hardware. The ATS consists of the automatic test equipment (ATE), the test program sets (TPSs), and associated software. The associated software includes the architecture the TPSs run on, known as the control software or test station test executive. In some cases, to sustain the legacy ATS, it is more practical to develop a replacement ATE with the latest instrumentation, often in the form of commercial off-the-shelf (COTS) hardware and software. The existing TPSs, including their hardware and test programs, then need to be transported, or translated, to the new test station. In order to understand how to sustain a legacy ATS by translating TPSs, one must realize the full architecture of the legacy ATS to be replaced. It must be understood that TPS transportability does not only include translating the original TPS from an existing language (such as ATLAS) to a new language (such as "C") to run on a new test station, but includes transporting the run-time environment created by the legacy ATS. This paper examines the similarities and differences of legacy ATE and modern COTS ATE architectures, how the ATS testing philosophy impacts the ease of TPS transportability from legacy ATE to modern-day platforms, and what SEI has done to address the issues that arise out of TPS transportability.     

Engineering in a virtual environment

The authors review virtual environment technology and its application to the aerospace industry. Virtual environment systems have three components: sensors, effectors, and interlinkage hardware and software. Virtual environment tools used by the aerospace industry include the Multi-dimensional, User-oriented, Synthetic Environment (MUSE); Cave Automatic Virtual Environment (CAVE); and Immersadesk. Engineering applications include design and manufacture of aerospace systems, maintenance, and repair.     

基于 FACE 思想的软件通用运行环境设计

未来机载能力环境（FACE）思想由美国军方、工业界和学术界共同发起，它针对机载航空电子软件系统提出了一种新的业务模型和参考架构。通过制定参考架构核心元素间的接口标准以及定义基于共识的通用数据模型可以为软件模块的跨平台重用提供便利。本文通过分析 FACE 参考架构的核心思想，结合实现层面的具体考虑，提出了软件通用运行环境的设计方案，旨在硬件计算平台上进一步搭建一个软件计算平台，使得应用软件模块在能够正常运行的基础上尽可能地实现“一次开发，多次应用”。     

Next generation space avionics: layered system implementation

Advances in electronics over the past decade have produced major improvements in the power and flexibility of computer systems. Unfortunately current avionics systems for space applications typically have not leveraged these COTS advantages. A decade ago, the state-of-the-art for avionics systems made a step change to the Integrated Modular Avionics (IMA) used in the Boeing 777. This next generation avionics architecture is not based upon traditional Byzantine redundancy structures, but on a truth-based scheme where each element knows when an internal failure occurs and removes itself from the system. IMA utilizes a lock-step microprocessor design that communicates to a COTS Backplane for input/output, and to a Virtual Backplane/spl trade/ (a reliable high-speed serial bus) for intra-system communication. The system functions are implemented using a time and space partitioned operating system. The entire system provides the simplicity of a simplex system, implements the highest level of reliability providing complete flexibility to reconfigure both software applications and hardware interfaces, allows for rapid prototyping using low-cost COTS hardware, and is easily expandable beyond the initial point implementation. As the only 5/sup th/ generation avionics architecture, the concepts incorporated into Honeywell's IMA are ideally suited to be the backbone of the next generation Space Exploration Program avionics architectures.     

Software architecture requirements for DoD automatic test systems

The DoD has achieved success with recent automatic test equipment (ATE) families, as evidenced by the navy's consolidated automated support system (CASS) and the army's integrated family of test equipment (IFTE) programs. However, as these systems age, the increased requirements for technology insertion due to instrument obsolescence and the demands of advanced electronics are becoming evident. Recent advances in test technology promise to yield reduced total ownership costs (TOC) for ATE which can incorporate the new technology. The DoD automatic test system (ATS) executive agent office (EAO) objective is to significantly reduce total ownership cost. Several objectives have been identified including use of synthetic instruments, support for legacy test product sets (TPSs), and more efficient ways of developing TPSs. The NxTest software architecture will meet the objectives by providing an open systems approach to the system software. This will allow for the incorporation of commercial applications in the TPS development and execution environments and support current advances in test technology     

Implementing reusable, instrument independent test programs in thefactory

Development of computer programs that control test sequences on Automatic Test Equipment (ATE) is costly and time consuming. Test Programs are usually written by specifying the instruments to be used in the ATE and the sequence of the setup and measurement parameters for these instruments. Reuse of test program software on other ATE is usually not possible without rewriting, revalidating and re-releasing the programs. This paper describes an implementation of a test program software development system and a standard of software runtime architecture used in our factories. The object-oriented development environment and its associated class libraries allow test programs to be written without knowledge of the ATE on which they will be run. Two main principles guided the design: the software architecture was based on recognized formal and industry standards; and our implementation used commercial off-the-shelf software products when possible. Emerging standards such as the IEEE-1226 (ABBET) as well as defacto industry standards including VXI Plug and Play have made our implementation possible. The current draft of the ABBET and P&P standards do not promote this instrument independence, but it is hoped that this will be added as the standards mature. Three immediate benefits are: cost savings that result from reusing validated test programs; cycle time reductions that result from concurrently developing test program software and ATE; and software defect reductions that result from using proven software     

基于虚拟无线电技术的航天测控系统设计

为了适应未来航天测控系统的发展趋势,提出了VRTCS（虚拟无线电测控系统）硬件平台和软件系统的基本结构。以通用高性能计算机作为系统的硬件平台,采用分层结构模型设计系统体系结构,使得航天测控系统具备更好的通用性和灵活性。阐述了VRTCS的基本概念和总体结构,对系统各组成部分的功能、组成和用途进行了分析;对测控系统中构件进行分层设计,开发原型软件实现测控系统的核心应用;以统一载波测控系统为模型,通过测控信号接入试验,验证了VRTCS的可行性。     

面向适航认证的模型驱动机载软件构件的安全性验证

 在软件开发的过程中为适航认证提供证据,已成为机载软件开发的研究热点。现代复杂机载软件多为构件化分布式架构,如何有效验证构件之间安全性依赖关系与适航认证标准当中规定目标的一致性,是机载软件设计阶段的一个重要问题。首先,使用系统建模语言(SysML)块图建立带有安全性特征的系统静态结构模型,将其转换为块依赖图以便进行精确的形式化描述。在此基础上给出形式验证方法,检验系统静态结构模型中的安全性依赖关系与适航认证标准中所规定目标之间是否一致。最后,通过一个飞机导航系统的例子说明如何将该方法应用于机载软件开发的过程中。利用这种方法对系统静态结构模型的安全性依赖关系进行验证,能够提高系统整体的安全性,并为适航认证提供证据。     

基于管道-过滤器模式的机载导航数据库格式化技术研究

针对飞行管理系统机载导航数据库应用需求,以管道-过滤器模式的软件架构体系为基础,设计了机载导航数据库格式化软件,实现标准导航数据格式到机载导航数据库格式的转换,生成适用于飞行管理系统的机载导航数据库文件系统。在分析机载导航数据库格式化的需求上,采用一种改进的管道-过滤器模式,通过裁剪和筛选导航数据的方法,降低数据容量。利用Access数据库作为中间数据库,建立不同类别的数据表,实现数据的快速查询和对比。通过实际的验证和应用表明机载导航数据库格式化软件是可行的,生成的机载导航数据库文件系统符合飞行管理系统要求,格式化后的数据是正确的。