VFSim: Concurrent Fault Simulation at Register Transfer Level

VLSI testing is being pushed to the high-level based technology. In this paper a Verilog Register transfer level Model (VRM) for integrated circuits is proposed. The model provides a text format file, which is convenient and more practical for developing succeeding Register Transfer Level (RTL) test tools, such as fault simulation, test pattern generation and so forth. Based on the VRM, an RTL concurrent fault simulation approach is presented. After RTL fault models and super faults defined, the concurrent fault simulation algorithm is given. The corresponding RTL concurrent fault simulator, VFSim, was implemented. The initial experiments show that the RTL fault simulator is efficient for VLSI circuits.     

基于混合遗传算法的RTL激励生成

寄存器传榆级（RTL）描述是目前应用最广泛的电路设计描述形式．在时序电路的RTL激励生成中，基于模拟的方法避免了帧扩展法庞大的搜索空间，但采用该方法常存在向量过多．质量不高等问题．本文充分考虑影响算法效率的各种因素，在此基础上，提出一种基于混合遗传算法的激励生成方法．该方法结合多种覆盖评估准则与故障模型作为激励生成目标，同时采用动态参数设置，实现全局-局域混合搜索机制．实验结果显示该方法是有效的．     

寄存器传输级测试用例生成算法

基于控制流图／数据流图层次模型,以分支覆盖、位功能覆盖以及语句可观测覆盖为目标,给出一个高层次测试用例生成算法,并最终实现一种可行的RTL级测试生成算法．实验结果表明,在较少的测试生成时间下,该算法可生成相对短的测试序列,得到与其他方法相当或略差的测试效果．此外,该算法因采用了测试用例技术而具有良好的灵活性．     

综合模块化航空电子平台网络故障注入策略

综合模块化航空电子（IMA）平台网络通信结构复杂，在进行故障注入测试时，存在难以选取合适的测试路径及等效、无效故障注入较多的问题。根据IMA平台网络通信结构特点，提出一种新的故障注入策略。首先，根据IMA平台网络对实时性和确定性的要求，提出一种基于通信链路的测试路径优化算法，生成最优测试路径，实现对IMA平台网络测试任务的有序覆盖；然后，在确定测试路径之后，采用有色Petri网（CPN）建模方法搭建测试案例自动生成模型，排除等效与无效故障，精简测路径中每个测试任务所需的测试案例。仿真结果表明，所提方法在测试次数与测试时间等方面均少于传统的故障注入策略，能够克服传统策略中的无序性及盲目性的缺点，降低测试的时间成本。     

一种低功耗BIST测试方法

通过分析RTL的代码和RTL的故障仿真可得到一组屏蔽向量,将这些屏蔽向量和随机向量应用到门级进行故障测试可提高系统的故障覆盖率并降低测试功耗。本文主要论述了利用RTL的功能信息进行低功耗BIST测试的方法,并通过其在标准电路中的应用阐述实现过程。     

Correlation-based fault-tolerant controller design for MIMO systems under the Youla parameterisation

This paper develops a correlation-based method into the Youla parameterisation structure for a fault-tolerant controller design strategy. By tuning the Youla parameters with the proposed correlation-based algorithm, a number of conditional faults described by the dual Youla parameters are attenuated. The traditional fault-tolerant control (FTC) schemes under the Youla parameterisation often require the gradient information of the defined cost function for minimisation, which is either tedious or even unfeasible with unknown fault model. However, the proposed correlation-based FTC algorithm in this paper can compensate the faults via system data without the explicit fault model or the cost function gradient information. It is also proved that the algorithm convergence can be achieved without identifying the unknown fault model. For illustration, a simulation example with corresponding comparisons are presented to show the effectiveness of the proposed method in the end.     

完全RTL的故障数目预测及故障覆盖率计算

在超大规模集成电路设计过程中，门级故障仿真通常因仿真速度太慢而不能满足市场需求，因此近年来寄存器传输级(RTL)故障仿真成了一个研究热点．已有的RTL的故障模型和故障仿真方法在计算系统的故障覆盖率时，对故障数目或者加权系数的计算需要将RTL设计综合到门级．文中在信号位宽和运算符类型的基础上，提出了一种在RTL预测故障数的手段，并由此得到完全RTL的故障覆盖率计算方法．实验结果证明了该方法的有效性．     

Verilog到C翻译器的设计与实现

介绍了一种将Verilog硬件描述转化到等价C／C＋＋代码的自动翻译器的实现过程，并给出了简化Verilog行为模型的疗法、非阻塞赋值串行化的优化算法和一些访存优化原则。该方法没计的翻译器的生成代码可直接由C/C＋＋编译器汇编成可执行程序后进行仿真。采用龙芯RTL作为系统输入的测试表明，该方法的仿真速度可比一般仿真软件有成倍的增加，并能在系统评估和分析上发挥显著的成效。     

A sliding mode observer-based strategy for fault detection,isolation, and estimation in a class of Lipschitz nonlinear systems

This article investigates the design and application of a sliding mode observer (SMO) strategy for actuator as well as sensor fault detection, isolation, and estimation (FDIE) problem for a class of uncertain Lipschitz nonlinear systems. Actuator FDIE is addressed by regrouping the system's inputs into a structure suitable for SMO design. Similarly, by filtering the regrouped outputs, a similar system structure can be developed for sensor FDIE problem. Once in the suitable form and under certain assumptions, nonlinear SMOs are proposed for actuator and sensor FDIE. A systematic LMI-based design approach for the proposed SMO is presented. Additionally, the article addresses four problems, namely: (P1) What are the conditions for isolating single and/or multiple faults? (P2) What is the maximum number of faults that can be isolated simultaneously? (P3) How should one design SMO-based FDI approach in order to achieve multiple fault isolation using as few observers as possible? (P4) How can one estimate the shape of the faults? To solve the above problems, a new concept called fault isolation index (FIX) is proposed for actuator and sensor FDIE. It is proved that fault isolation can only be achieved if FIX?≠?0, and also that the maximum number of faults that can be isolated is equal to FIX. Using the proposed fault isolation strategy and by treating some healthy inputs or outputs as unknown inputs, a systematic FDIE design scheme using a bank of nonlinear SMOs, which provides a solution for the four problems is provided. An example is used to illustrate the proposed ideas. The simulation results show that the proposed FDIE scheme can successfully detect and isolate both slowly and fast-changing actuator faults. It is also shown that accurate estimation of actuator faults can be achieved.     

基于代理的航天器自主运行仿真系统设计与验证系统设计

针对目前航天器自主健康管理功能测试过程中,由于故障模拟手段不足造成测试覆盖率低,测试项目不完备,测试效率低等问题,提出一种基于代理的航天器自主健康故障仿真验证系统设计方案;基于该方案实现的故障仿真系统支持根据通用化航天器自主健康故障检测模型,严格按逻辑和时序,无延迟、持续的向全实物或半实物测试系统自动注入故障状态表征参数,模拟航天器整器或任意分系统、单机、软件的故障状态,模拟弥补了长期以来在实物测试环境下,整器故障模式测试覆盖率低,测试用例复用性差的问题;实践证明,此方法能将测试覆盖率提升至95%以上,并将测试时间缩短至传统方式的1/6,有效提升被测航天器产品可靠性。     

SoC设计中嵌入存储器对ATPG的影响

在ASIC设计中，越来越多地采用了So（systems-on0a-chip）方法，同时也因为采用各种IP核和嵌入存储器，给芯片的设计和测试带来了复杂性，特别是在ATPG中这些单元对故障覆盖率有较大的影响，现在已经有一些测试嵌入存储器本身的方法，但这些方法一般不考虑嵌入存储器对周围逻辑可测性的影响，在分析了嵌入存储器对ATPG的影响后，提出了消除这些影响的RTL级的DFT方法，这种方法得到了实验的检验。     

长期在轨推进系统故障诊断实时仿真技术研究

为了解决长期在轨航天器易出现故障的推进系统故障常规地面检测费时费力且无法完全包络全部故障模式的问题,提出了长期在轨推进系统故障诊断实时仿真技术方案,建立了长期在轨推进系统故障诊断实时测试平台。通过建立推进系统实时仿真模型,实现对长期在轨推进系统的实时仿真;依托实时测试平台对推进系统故障诊断策略进行仿真优化、对在轨飞行器故障进行诊断、并对处置预案进行验证支持故障处置决策。长期在轨推进系统故障诊断实时测试平台有效缩短了器上故障诊断策略的优化迭代周期,同时节省了大量原本用来进行试车的经费。     

基于未知输入集员滤波器的不确定系统故障诊断

针对一类具有参数不确定性和未知扰动的线性系统,提出了一种新的执行器故障诊断方法.将指定执行器故障视为未知输入,利用全对称多胞形近似状态边界,本文设计了一种未知输入全对称多胞形集员滤波器,以估计测量输出的上下边界.在此基础上,提出了一种利用一组未知输入滤波器的故障检测与分离策略.通过一个飞行控制系统的数值仿真验证了所提出方法的有效性.     

基于广义回归神经网络的传感器故障诊断研究

针对诊断传感器偏置故障与漂移故障的难点问题,提出了一种基于广义回归神经网络(GRNN)的传感器故障诊断方法。该方法充分利用控制系统闭环回路测控信息,建立一组多输入单输出GRNN观测器,通过将观测器输出与传感器实际输出相比较获取残差序列,获得基于残差序列的传感器偏置故障和漂移故障的辨识策略,实现控制系统传感器故障在线诊断。仿真结果表明:该方法可以快速准确地检测和分离传感器故障,辨识传感器故障类型、故障大小以及故障发生的时间。     

Robust fault and icing diagnosis in unmanned aerial vehicles using LPV interval observers

This paper proposes a linear parameter varying (LPV) interval unknown input observer for the robust fault diagnosis of actuator faults and ice accretion in unmanned aerial vehicles (UAVs) described by an uncertain model. The proposed interval observer evaluates the set of values for the state, which are compatible with the nominal fault‐free and icing‐free operation and can be designed in such a way that some information about the nature of the unknown inputs affecting the system can be obtained, thus allowing the diagnosis to be performed. The proposed strategy has several advantages. First, the LPV paradigm allows taking into account operating point variations. Second, the noise rejection properties are enhanced by the presence of the integral term. Third, the interval estimation property guarantees the absence of false alarms. Linear matrix inequality–based conditions for the analysis/design of these observers are provided in order to guarantee the interval estimation of the state and the boundedness of the estimation. The developed theory is supported by simulation results, obtained with the uncertain model of a Zagi Flying Wing UAV, which illustrate the strong appeal of the methodology for identifying correctly unexpected changes in the system dynamics due to actuator faults or icing.     

面向HDL描述基于路径覆盖的模拟矢量自动生成方法研究

提出和实现了一种面向HDL描述基于路径覆盖的模拟矢量自动生成方法,该方法在约束生成时只考虑控制语句的条件表达式，可有效避免生成冗余约束；利用扩展的决策图模型解决了中间信号到初始输入的传播问题和信号依赖关系问题，以及处理各种HDL描述风格的问题；采用约束逻辑编程方法解决了由位、位向量和整型变量组成的约束系统的统一处理问题,实验结果表明该方法能加快模拟矢量生成速度，提高路径覆盖率．生成的模拟矢量也能用于低层次设计验证和故障模拟，加快了设计进度,将该方法的原型系统用于一个32位微处理器核RTL级验证，发现了RTL级设计描述中的错误．     

面向专用指令集处理器设计的软硬件协同验证

为提高专用指令集处理器设计中的验证效率和覆盖率,将专用指令集处理器的寄存器传输级设计验证与汇编器、指令集模拟器等软件开发工具的测试相结合,提出一种软硬件协同验证方法。该方法按照覆盖率要求由软件自动产生测试程序和数据,将利用汇编器产生的机器指令输入到指令集模拟器和硬件仿真工具分别进行软硬件仿真,通过软硬件仿真结果自动比对得出联合验证结果。实践证明,该方法能够有效提高验证效率和覆盖率,缩短验证周期。     

数字系统单加权集下随机测试生成方法

为在不引入额外的硬件开销以下较短的测试序列获得较高的故障覆盖率，提出一种基于细胞自动机（CA）的数字集成电路加权随机测试方法。该方法利用可测性测度建立反映故障侦查代价的可测性代价函数，对此函数的寻优得到被测电路主输入处的权值，再由一维混合型CA实现了该权值下的随机序列。对标准电路的实验验证了该方法是一种有效的、且便于BIST的应用的测试生成算法。