一种能力驱动的开放式航电软件架构

在新一代IT 技术环境下,传统单平台“烟囱式”的航电软件架构和开发模式面临着变革的挑战。针 对航电软件系统软硬件耦合紧密、规模大、复杂度高的特点,提出了一种能力驱动的开放式航电软件架构环境, 用于大型复杂航电软件系统的多团队开发。除了软件计算环境(SCE) 为可移植的应用软件组件提供跨飞机平台 的能力外,该环境还包括一个航电软件架构规范,保障架构的开放性、可移植性、互操作性等,以及规范基于 模型驱动的软件开发流程,用于快速部署、升级和替换可移植的软件组件。为了证明该开放式航电软件架构环 境的可行性和有效性,本文结合实际需求进行了实例研究。     

基于DO一178B的结构覆盖分析研究

结构覆盖分析（SCA）是基于DO一178B的软件验证的重要组成部分。由于DO一178B仅提出目标活动要求,不提供具体的工程技术方法,如何进行结构覆盖分析是困扰国内航电软件开发和验证的一大难题。通过与国外航电设备厂商的多年的软件国际合作,以及对DO一178B软件结构覆盖分析具体要求的深入研究,提出了一个结构覆盖分析过程和具体的实现方法。在多个软件国际合作项目中的实际应用表明,的研究成果满足DO一178B结构覆盖分析的要求。     

机载嵌入式软件可靠性设计研究

机载航电系统的可靠性问题越来越受到关注,软件可靠性设计要抓住两个方面,软件开发过程和软件开发方法。本文根据机载嵌入式系统软件的特点,讨论了软件开发过程在可靠性方面的考虑,还有在需求、设计、编码阶段使用的相关设计方法和技术。     

综合航电显控仿真系统的设计与实现

介绍了一种综合航电显控仿真系统的设计思想和实现方法。提出了采用COTS思想进行该仿真系统设计的思路，运用真实显控分系统OFP软件的移植，保证了系统功能的一致性。重点设计了硬件接口（显示、控制、总线）功能的仿真，并运用触摸屏和模拟遥杆实现人机界面仿真。     

基于模型的航电系统集成验证技术研究

为了满足系统集成度高、交联关系复杂的航电系统集成验证需求,提出了基于模型的航电系统集成验证技术。详细介绍了基于模型的航电系统仿真和测试方法,航电系统仿真建模规范,以及基于模型运行的航电系统集成验证平台。通过在航电系统集成过程中的应用,基于模型的集成方法有效地提高了航电系统集成效率,保证了航电系统集成准确度。该方法可应用于航电系统全数字集成、半物理集成和全实物动态集成,保证各阶段试验的衔接,持续提升航电系统集成工作的技术水平。     

新一代飞机航电系统的综合化趋势及关键技术

基于飞机航电系统的发展演变历史,阐述了新一代飞机航电系统的综合化演变过程和主要特征,研究了新一代飞机综合化航电系统的结构趋势,提出了提高航电系统综合化水平需重点研究的关键技术。     

基于射频综合的综合航电系统介绍

本文通过对现代飞机综合航电系统与基于可编程技术的航电系统的对比分析表明，基于可编程技术的航电系统设计更加灵活，系统易于重构，系统升级更加方便，冗余度更高，大大改善了飞机的性能，提高了航电系统的可靠性，为飞机其他系统的设计提高了更大的灵活性，代表未来航电系统的发展方向。     

空间站环境COTS器件容错技术综述

由于空间站环境的总辐照剂量影响较小,采用商用现货(COTS)器件替代传统高等级抗辐照器件来降低成本是有效的方法,但是随着工艺尺寸的缩小,COTS器件受单粒子效应的影响越来越突出。为抑制单粒子效应,COTS器件通常需要采用多种软硬件容错设计。基于上述应用需求,对国内外采用COTS器件的低轨卫星及其相关容错技术进行了总结和分析,分别对存储器、SRAM型FPGA、DSP、CPU处理器进行了容错技术的研究和分析,总结了各类容错技术的现状及发展趋势。并针对上述四类COTS器件,分别给出在空间站环境下的容错设计建议。     

基于ADS2的航电系统综合测试平台设计与实现

介绍了基于ADS2的航电系统综合测试平台设计方案,通过分析航电系统的基本组成和当前航电系统测试对测试平台的迫切需求,提出构建航电系统综合测试平台的技术方案及测试系统的顶层逻辑架构、物理架构及功能实现.     

商用货架产品的可靠性风险控制方法

归纳提出了选用COTS的五项原则,分析了COTS可靠性风险源,指出了COTS可靠性工作的重点,提出了型号研制中COTS可靠性风险控制的程序与方法,最后还分析了尚需进一步开展的COTS可靠性管理与技术研究工作。     

Open systems architecture solutions for military avionics testing

Raytheon makes extensive use of open systems architecture methods in developing special test equipment (STE) for testing military avionics equipment. Such use has resulted in significant cost and schedule savings in the development of production test equipment for radar and infrared systems. With open systems architectures, a test system can be assembled using COTS products. This brings economies of scale to test equipment, which is normally built in very low quantities. Therefore, the potential cost savings due to COTS usage is proportionately greater in STE than in the higher volume avionics systems that are tested. A second major benefit of using COTS products is that test system development schedule cycle time is greatly reduced. This paper describes the application of Open Systems Architectures (OSA) to avionics testing. The following major architectures are surveyed: VME bus, VXI bus, IEEE GPIB, IEEE 1149.1 JTAG test bus, 1553 Military Bus, Fibre Channel, and COTS Test Applications Software. We describe how the benefits of OSA have been extended at Raytheon into achieving vertical test commonalities. The flexibility of OSA can be exploited to provide an overall optimum test solution, taking all levels of test into account. For example, test systems can be tailored with COTS products to provide integrated methods for avionics tests at the module, unit, and system levels. Test systems can be configured to maximize the reuse of COTS hardware over all test levels. Test software can also be programmed to optimize such reuse over levels of test. Additional test verticality synergies derived from such OSA usage are described, including: test false alarm avoidance; test cones of tolerance optimization; and efficient test of field returns     

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.     

Replacement strategy for aging avionics computers

With decreasing defense dollars available to purchase new military aircraft, the inventory of existing aircraft will have to last many more years than originally anticipated. As the avionics computers on these aging aircraft get older, they become more expensive to maintain due to parts obsolescence. In addition, expanding missions and changing requirements lead to growth in the embedded software which, in turn, requires additional processing and memory capacity. Both factors, parts obsolescence and new processing capacity, result in the need to replace the old computer hardware with newer, more capable microprocessor technology. New microprocessors, however, are not compatible with the older computer instruction set architectures. This generally requires the embedded software in these computers to be rewritten. A significant savings-estimated in the billions of dollars-could be achieved in these upgrades if the new computers could execute the old embedded code along with any new code to be added. This paper describes a commercial-off-the-shelf (COTS)-based form, fit, function, and interface (F³I) replacement strategy for legacy avionics computers that can reuse existing avionics code “as is” while providing a flexible framework for incremental upgrades and managed change. It is based on a real-time embedded software technology that executes legacy binary code on the latest generation COTS microprocessors. This technology promises performance improvements of 5-10 times that of the legacy avionics computer that it replaces. It also promises a 4× decrease in cost and schedule over rewriting the code and provides a “known good” starting point for incremental upgrades of the embedded flight software. Code revalidation cost and risk are minimized since the structure of the embedded code is not changed, allowing the replacement computer to be retested at the “blackbox” level using existing qualification tests     

云服务技术在航电软件研发中的应用研究

航空电子系统硬件的发展，为云服务技术在航空领域的应用提供了可能。借助虚拟化及容器管理技术， 将机载计算资源进行池化管理，并借助服务化技术，将复杂航电软件拆分为可协作的独立模块，能够实现航电 软件的快速构建、灵活部署，并提高航电软件之间的互操作能力。本文讨论了云服务技术在航空领域的应用现 状，研究并提出了一种应用于航电软件研发的云服务架构，给出了服务化和容器管理平台的实现方案，并构建 了应用原型验证环境。     

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     

IMA aircraft improvements

Integrated modular avionics (IMA) is being suggested as the means by which new capabilities can be deployed on aircraft at an affordable cost. RTCA SC-200 is presently considering the guidance document for IMA. All of the functionality that IMA offers can be achieved through a conventional federated architecture; however, the cost, size, and weight penalties of the federated solution make it economically infeasible. IMA is seen as the way forward. It is assuming greater importance as the aircraft industry transitions to commercial-off-the-shelf (COTS) technology with its attendant obsolescence and reliability concerns. IMA may be one of the most cost-effective ways by which rapid obsolescence can be managed. Ironically, this move to COTS is also the greatest threat to IMA systems. IMA achieves reductions in size, cost, and weight by providing a set of flexible hardware and software resources that can be statically or dynamically mapped to a set of required avionics functional capabilities. This introduces a number of new complexities such as mixed criticalities and reconfiguration. We do not address these issues herein. Rather we discuss the mechanisms by which electronics degrades and how a classical safety assessment of a reconfigurable IMA system can be ified by this degradation. We argue that, with the advent of COTS, it is no longer justifiable to consider that electronics has an effectively constant failure rate. Physical considerations suggest that electronics failure occurs when environmental and operating stress causes the accumulation of damage to the underlying structures to exceed the threshold strength of the constituent materials and interfaces. Finally, we suggest how finite-life electronics effects may be mitigated.     

基于并行工程的航空嵌入式软件测试过程研究

航空嵌入式软件市场不断动荡与激烈竞争的局面对航空嵌入式软件测试提出了新的挑战,商业化的第三方软件测试面临着质量、进度、成本等问题,而良好的软件过程与持续的过程改进是解决这些问题的一个途径。从对并行工程的研究入手,将并行工程的方法运用到航空嵌入式软件测试实践中,寻求基于并行工程的航空嵌入式软件测试过程,用于解决以上问题。     

A cost effective critical space systems design approach

NASA-ISC requires avionics platforms capable of serving a wide range of applications in a cost-effective manner. In part, making the avionics platform cost effective means adhering to open standards and supporting the integration of COTS products with custom products. Inherently, operation in space requires low power, mass, and volume while retaining high performance, reconfigurability, scalability, and upgradability. The Universal Mini-Controller (UMC) project is based on a modified PC/104-Plus architecture while maintaining full compatibility with standard COTS PC/104 products. The architecture consists of a library of stackable building block modules, which can be mixed and matched to meet a specific application. A set of NASA developed core building blocks, (e.g. processor card, analog input/output card, high level analog card, and a Mil-Std-1553 card) were constructed to meet critical functions and unique interfaces     

机载嵌入式软件的系统测试

针对航空电子系统的功能特点,分析了某航电分系统控制管理计算机软件的特征和要求,结合机载嵌入式软件的系统测试需求,提出利用航电分系统设计开发试验平台,通过总线上的故障注入和数据采集方法,实现机载嵌入式软件的系统测试。     

Use of service history for certification credit for COTS [avionic software]

Much has been written in the last ten years about how the use of commercial-off-the-shelf (COTS) components would revolutionize the aerospace industry avionics, communication, navigation, surveillance/air traffic management (CNS/ATM) as well as global air traffic management (GATM). Civil aviation authorities around the world have been faced with numerous requests to certify aircraft containing increasing percentages of COTS components, much of it never designed or intended for use in the safety critical environment of an aircraft. Product service history is one method for demonstrating that such software is acceptable for use. In theory, product service history would seem to be a fairly simple concept, both to understand and to apply. However, in practice, such use has proven extremely problematic, as questions of how to measure the historic performance and the relevance of the provided data have surfaced. This paper elaborates a research effort funded by the United States Federal Aviation Administration to collect, analyze, and synthesize what is known and understood about applying product service history. The effort is limited to the topic of software product service history as applied in the certification of airborne systems and equipment.