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     

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     

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。     

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.     

Advances in DoD's ATS Framework

The Automatic Test System (ATS) Executive Directorate (ED) is charged with developing objectives for the Department of Defense (DoD) ATS modernization. The DoD ATS Framework Working Group (FWG) was established by the ATS ED to create a Framework addressing these objectives. The FWG consists of two sub-groups: Management, that includes members from all of the DoD Services, and Technical. The Framework is made up of key elements and associated specifications and standards that form the open system architecture approach for DoD ATSs. In addition to creating and updating key element definitions, the FWG focuses on identifying commercial ATS related specifications that might satisfy the elements in the Framework. The standards specified in the DoD ATS Framework are documented in the DoD's Information Technology Standards Repository (DISR) and thereby become a mandatory requirement for all DoD ATS acquisitions. The Framework is also being specifically called out in DoD ATS requirements documents so that its standards are incorporated in future DoD ATS acquisitions, such as the Navy's eCASS.     

利用IVI驱动程序在LabVIEW中构建测试系统

讨论了IVI驱动程序的特点、测试系统结构、MAX配置IVI 仪器过程,介绍了在LabVIEW环境中实现IVI编程的方法.     

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。     

EUROPEAN NETWORK FOR THE NUMERICAL SIMULATION OF SPACE PLASMAS

The Cluster mission of the European Space Agency (ESA) will allow, for the first time three-dimensional measurements in key regions of the Earth's magnetosphere to be carried out. The European Numerical Simulation Network (ENSN) aims at providing a theoretical support to the mission. We describe the achievements of the ENSN during its first period of activity 1991–1994, during which the network was funded by the European Union. In particular, the ENSN has set up (i) thematic Working Groups on the prime scientific goals of the mission, (ii) a code development Working Group to develop numerical simulation codes specifically adapted to studying magnetospheric boundaries and the corresponding scale mixing, and (iii) software models of Cluster instruments to test in a numerical simulation what the set of four instruments will measure.     

Proposal to TPS delivery in 4 months?

Decreasing the often lengthy Test Program Set (TPS) development time is a high priority for both DoD and commercial industry. A protracted test development time for a commercial product can make or break its success. It can impact time-to-market goals for a product, which in turn, can result in a loss of market share. Though the DoD world has different objectives, they, too, are concerned with long test development times which can increase costs and jeopardize a weapon system's mission readiness. The case study for this paper is a test system developed by BAE Systems in less than four months to meet a commercial customer's stringent schedule requirements. The factors that contributed to the success of this project are examined, as is their relevance to the DoD world. The desire is to apply relevant lessons learned from the commercial industry to DoD programs, yielding a decrease in TPS development time     

The defense acquisition system too late for the scalpel; bring outthe meat axe!

The problems discussed include that associated with the requirements process which leads to overspecification and an overly rigid approach to development, and a procurement system which is bloated and grossly inefficient. The bureaucracy in the DoD acquisition system has grown steadily from the 1960's to 1990's. Each problem encountered, and there have been serious ones, has resulted in the addition by the DoD or Congress of another wicket to get through, another set of unended peripheral tasks, another layer of checks, meetings, reports. Each addition was an intended improvement which in the long run has only made things worse. The DoD rightly asked for greater reliability and the reliability/maintainability/availability RMA, cult was born. Recommendations dealing with these problems are discussed     

Software architecture for building

Test system developers can benefit greatly from a software architecture that allows for easy interchangeability of instruments in those systems. Using open industry standard software architectures such as Virtual Instrument Software Architecture (VISA), and Interchangeable Virtual Instruments (IVI), developers are able to create systems with interchangeable test instrumentation. This paper describes the VISA and IVI software standards and demonstrates how their use within a broader software architecture, which includes standard development environments and flexible test executive software, facilitates the creation of interchangeable test systems     

Open system concepts for modular avionics

Advanced communications, guidance and navigation systems play key roles in determining superiority of one combat aircraft over another. The use of advanced technology is essential to meeting the mission requirements of present as well as future aircraft. Modular avionics are being used in next generation aircraft, such as the Air Force F-22 fighter and the Army Comanche helicopter, as the means of achieving higher levels of performance, including reduced volume and improved adaptability, maintainability, and expandability. New system acquisitions such as Joint Strike Fighter will attempt to achieve these same performance levels but at dramatically reduced life cycle cost. Retrofit applications will also take on increasing roles in meeting this affordability need as the Department of Defense (DoD) struggles to maintain readiness in the face of the shrinking defense budget. The government is encouraging the use of open standards practices as a means of addressing the affordability issue. The Open Systems Joint Task Force (OS-JTF), formed in September 1994, is chartered to “sponsor and accelerate the adoption of open systems in weapons systems and subsystem electronics to reduce life-cycle costs and facilitate effective weapon system intra- and interoperability”. The purpose of this paper is to relate the concept of open systems to modular avionics. It discusses the key attributes of an open systems approach and identifies key technologies necessary for its success     

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     

“Test technology and commercialization-past, present andfuture”. Theme of AUTOTESTCON '96

AUTOTESTCON '96, jointly sponsored by AESS and the Instrumentation and Measurement Society (I&MS), was held September 16-19 in Dayton, OH, the birthplace of aviation. As the largest test conference, it provides a valuable forum for the exchange of information relating to automatic test systems (ATS). The conference has continued to grow both in attendance and in exhibition space. This year's conference emphasized improving test system effectiveness in the presence of exploding computer technology and the changing military and commercial environment. The impact of DoD acquisition reform on test was also examined     

AFRL Cryogenic Technology Development Programs

This is an overview of the cryogenic refrigerator and cryogenic integration programs in development and characterization under the Cryogenic Technologies Group, Space Vehicles Directorate of the Air Force Research Laboratory (AFRL). The vision statement for the Air Force Research Laboratory Cryogenic Technologies Group is to support the space community as the center of excellence for developing and transitioning space cryogenic thermal management technologies. The primary customers for the AFRL cryogenic technology development programs are Ballistic Missile Defense Organization (BMDO), the USAF SBIRS (space based infrared) Low program office, and DoD space surveillance programs. This describes a variety of Stirling, pulse tube, Reverse Brayton, Joule-Thomson, and Sorption cycle cryocoolers currently under development to meet current and future Air Force and DoD requirements. The AFRL customer single stage cooling requirements at 10 K, 35 K, 60 K, 150 K, and multi-stage cooling requirements at 35/60 K are addressed. In order to meet these various requirements, the AFRL Cryogenic Technologies Group is pursuing various strategic cryocooler and cryogenic integration options. The Air Force Research Laboratory is also developing several advanced cryogenic integration technologies that will result in the reduction in current cryogenic system integration penalties and design time. These technologies include the continued development of the cryogenic systems integration model (CSIM), 60 K, and 100 K thermal storage units and heat pipes, cryogenic straps, thermal switches, and development of an integrated lightweight cryogenic bus (CRYOBUS).     

An integrated systems engineering approach to aircraft design

The challenge in Aerospace Engineering, in the next two decades as set by Vision 2020, is to meet the targets of reduction of nitric oxide emission by 80%, carbon monoxide and carbon dioxide both by 50%, reduce noise by 50% and of course with reduced cost and improved safety. All this must be achieved with expected increase in capacity and demand. Such a challenge has to be in a background where the understanding of physics of flight has changed very little over the years and where industrial growth is driven primarily by cost rather than new technology.The way forward to meet the challenges is to introduce innovative technologies and develop an integrated, effective and efficient process for the life cycle design of aircraft, known as systems engineering (SE). SE is a holistic approach to a product that comprises several components. Customer specifications, conceptual design, risk analysis, functional analysis and architecture, physical architecture, design analysis and synthesis, and trade studies and optimisation, manufacturing, testing validation and verification, delivery, life cycle cost and management. Further, it involves interaction between traditional disciplines such as Aerodynamics, Structures and Flight Mechanics with people- and process-oriented disciplines such as Management, Manufacturing, and Technology Transfer.SE has become the state-of-the-art methodology for organising and managing aerospace production. However, like many well founded methodologies, it is more difficult to embody the core principles into formalised models and tools. The key contribution of the paper will be to review this formalisation and to present the very latest knowledge and technology that facilitates SE theory. Typically, research into SE provides a deeper understanding of the core principles and interactions, and helps one to appreciate the required technical architecture for fully exploiting it as a process, rather than a series of events.There are major issues as regards to systems approach to aircraft design and these include lack of basic scientific/practical models and tools for interfacing and integrating the components of SE and within a given component, for example, life cycle cost, basic models for linking the key drivers. The paper will review the current state of art in SE approach to aircraft design and identify some of the major challenges, the current state of the art and visions for the future. The review moves from an initial basis in traditional engineering design processes to consideration of costs and manufacturing in this integrated environment. Issues related to the implementation of integration in design at the detailed physics level are discussed in the case studies.     

用MFC开发 OpenGL的三维图形功能

OpenGL是目前国际流行的开放式图形标准 ,它具有功能强大的三维图形库 ,而VisualC 6 .0具有完善的MFC和AppWizard ,如何将二者完美地结合在一起 ,在Win32环境下开发出高品质的三维图形应用程序是一个值得深入研究的课题。本文介绍了作者在工程实践中利用MFC开发OpenGL三维图形功能的关键技术。     

Near term approach to data relay for satellites under test

The increasing need for a continuous communications link with U.S. Department of Defense (DoD) spacecraft during test missions in low Earth orbit (LEG) has resulted in greater interest in geosynchronous data relay services. This may be a more economical alternative to building additional remote tracking stations for the Air Force Satellite Control Network (AFSCN), and avoids tying up operational assets for a test mission. A low-cost near-term approach for such a space-based data relay system would utilize two existing Defense Satellite Communication System III spacecraft, two existing ground terminals, and a small, standardized terminal using autonomous antenna pointing for the space vehicle under test. Such a system design is presented     

水雾灭火技术在民用飞机上的应用现状

由于环境保护的需要,寻找适合民用飞机的哈龙替代灭火剂是急需解决的问题,在可选择的多种灭火剂或灭火系统中,水雾灭火系统由于其环保、清洁、高效、稳定且无毒害等优点而成为目前最有希望的哈龙替代灭火剂。首先介绍了水雾灭火系统的灭火机理及其独特优势,以及国际航空火灾防护工作组(IASFPWG)制定的最低性能标准(minimum performance standard,简称 MPS)和测试结果,研究显示水雾灭火系统很好地通过了MPS要求。然后对影响水雾灭火系统性能的因素进行研究分析：提高工作压力和流量系数可有效提高水雾灭火系统灭火能力,通过调节喷雾锥角和雾滴粒径可改善水雾灭火系统灭火性能;添加一定浓度的盐类化合物、表面活性剂也可提高水雾灭火系统的灭火能力,且不同添加剂具有不同的最佳浓度比例。