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Showing papers presented at "AUTOTESTCON in 2007"


Book ChapterDOI
05 Nov 2007
TL;DR: This paper provides a high level architecture and includes descriptions of the OGC sensor interface and encoding standards that have been approved or are soon to be approved.
Abstract: This document provides a high level overview if the Sensor Web Enablement work of the Open Geospatial Consortium. This paper provides a high level architecture and includes descriptions of the OGC sensor interface and encoding standards that have been approved or are soon to be approved.

761 citations


Proceedings ArticleDOI
05 Nov 2007
TL;DR: The RVM, which is a Bayesian treatment of the support vector machine (SVM), is used for diagnosis as well as for model development, and the PF framework uses this model and statistical estimates of the noise in the system and anticipated operational conditions to provide estimates of SOC, SOH and SOL.
Abstract: The application of the Bayesian theory of managing uncertainty and complexity to regression and classification in the form of relevance vector machine (RVM), and to state estimation via particle filters (PF), proves to be a powerful tool to integrate the diagnosis and prognosis of battery health. Accurate estimates of the state-of-charge (SOC), the state-of-health (SOH) and state-of-life (SOL) for batteries provide a significant value addition to the management of any operation involving electrical systems. This is especially true for aerospace systems, where unanticipated battery performance may lead to catastrophic failures. Batteries, composed of multiple electrochemical cells, are complex systems whose internal state variables are either inaccessible to sensors or hard to measure under operational conditions. In addition, battery performance is strongly influenced by ambient environmental and load conditions. Consequently, inference and estimation techniques need to be applied on indirect measurements, anticipated operational conditions and historical data, for which a Bayesian statistical approach is suitable. Accurate models of electro-chemical processes in the form of equivalent electric circuit parameters need to be combined with statistical models of state transitions, aging processes and measurement fidelity, need to be combined in a formal framework to make the approach viable. The RVM, which is a Bayesian treatment of the support vector machine (SVM), is used for diagnosis as well as for model development. The PF framework uses this model and statistical estimates of the noise in the system and anticipated operational conditions to provide estimates of SOC, SOH and SOL. Validation of this approach on experimental data from Li-ion batteries is presented.

175 citations


Proceedings ArticleDOI
05 Nov 2007
TL;DR: The design of an integrated framework for on-board fault diagnosis and failure prognosis of a helicopter transmission component is introduced, and its main modules are described.
Abstract: This paper introduces the design of an integrated framework for on-board fault diagnosis and failure prognosis of a helicopter transmission component, and describes briefly its main modules. It suggests means to (1) validate statistically and pre-process sensor data (vibration), (2) integrate model-based diagnosis and prognosis, (3) extract useful features or condition indicators from data de-noised by blind deconvolution, and (4) combine Bayesian estimation algorithms and measurements to detect and identify the fault and predict remaining useful life with specified confidence and minimum false alarms.

41 citations


Proceedings ArticleDOI
05 Nov 2007
TL;DR: Three novel classifier fusion approaches are developed: class-specific Bayesian fusion; joint optimization of the fusion center and individual classifiers; and dynamic fusion, which demonstrate that the proposed fusion techniques outperform traditional fusion approaches.
Abstract: Faulty automotive systems significantly degrade the performance and efficiency of vehicles, and oftentimes are the major contributors of vehicle breakdown; they result in large expenditures for repair and maintenance. Therefore, intelligent vehicle health-monitoring schemes are needed for effective fault diagnosis in automotive systems. Previously, we developed a data-driven approach using a data reduction technique, coupled with a variety of classifiers, for fault diagnosis in automotive systems. In this paper, we consider the problem of fusing classifier decisions to reduce diagnostic errors. Specifically, we develop three novel classifier fusion approaches: class-specific Bayesian fusion, joint optimization of fusion center and of individual classifiers, and dynamic fusion. We evaluate the efficacies of these fusion approaches on an automotive engine data. The results demonstrate that dynamic fusion and joint optimization, and class-specific Bayesian fusion outperform traditional fusion approaches. We also show that learning the parameters of individual classifiers as part of the fusion architecture can provide better classification performance.

37 citations


Proceedings ArticleDOI
05 Nov 2007
TL;DR: The IDATS team has utilized a commercial off-the-shelf data mining software package called ThinkAnalytics in combination with custom software tools to find meaningful trends within the F/A-18 BIT and maintenance datasets.
Abstract: A large portion of Naval aircraft maintenance is driven by avionics-related deficiencies. Military avionics systems rely heavily on built-in test (BIT) to troubleshoot discrepancies during unscheduled maintenance. One study found that analyzing BIT codes for trends (both at the aircraft level and at the squadron level) and scheduling maintenance accordingly, increased aircraft operational availability (Ao) by twenty-two percent within a single squadron [1]. The study focused on F/A-18C aircraft over a forty-four month period. While this is a substantial increase, it takes into account only organizational level (O-level) BIT data. It does not include all available information, such as historical maintenance data, operating environment, and past repair history. The Integrated Diagnostics and Automated Test Systems (IDATS) team at Naval Air Systems Command (NAVAIR) Lakehurst is investigating the use of data mining to mitigate ambiguity within Naval avionics maintenance, with the intent of reducing costly and inefficient maintenance practices [2]. This includes building models from both aircraft historical maintenance data and BIT codes recorded to an aircraft's memory unit (MU) during a flight in order to identify trends in the data that would not be obvious or trivial to a maintainer. The IDATS team has utilized a commercial off-the-shelf (COTS) data mining software package called ThinkAnalytics in combination with custom software tools to find meaningful trends within the F/A-18 BIT and maintenance datasets. ThinkAnalytics is a real-time enterprise data mining tool that provided the necessary data mining functionality. Trends identified by the software are currently being validated by the user and system Subject Matter Experts (SMEs) to ensure that they are accurate, novel and/or non-trivial. Through the use of data mining, in combination with knowledge about how the system operates and communicates with other systems, BIT can be augmented to improve maintenance efficiency at all levels of maintenance.

34 citations


Proceedings ArticleDOI
01 Jan 2007

33 citations


Proceedings ArticleDOI
05 Nov 2007
TL;DR: This paper describes how a timed failure propagation graph (TFPG) based reasoner can be used to optimally diagnose failures in a complex real time system, such as an aerospace vehicle.
Abstract: This paper describes how a timed failure propagation graph (TFPG) based reasoner can be used to optimally diagnose failures in a complex real time system, such as an aerospace vehicle. The TFPG approach is a specific instantiation of model based diagnostic reasoning which has been well documented (Abdelwahed et al., 2004). The authors have been collaborating over the last several years to identify the practical issues that are associated with the application of the TFPG reasoner for real time fault isolation in a large scale, dynamically changing environment; the resulting modifications to the reasoner have also been previously documented (Karsai et al., 2006) (Abdelwahed & Karsai, 2007). The focus of this paper is to illustrate, using a notional but representative fuel system case study, how the TFPG reasoner can efficiently and effectively diagnose both single and multiple failure scenarios. Using actual results obtained for this example, we will explore the practical implementation challenges that would typically be encountered when building a diagnostic reasoner implementation, and then demonstrate the TFPG features that have been implemented to address these issues.

27 citations


Proceedings ArticleDOI
05 Nov 2007
TL;DR: In this paper, the ringing characterization was used to evaluate the power electronic circuit and electric machine against transistor degradation, which demonstrated its viability as a practical real-time power device health state indicator.
Abstract: Embeddable features easily incorporated in traditional power drive systems are identified for prognostic health management (PHM) systems. This novel technique utilizes the original PWM waveform produced by the inverter to evaluate the power electronic circuit and electric machine against transistor degradation. Evaluation of the primary feature, ringing characterization, with experimental data demonstrates its viability as a practical real-time power device health-state indicator.

25 citations


Proceedings ArticleDOI
05 Nov 2007
TL;DR: The development of the main parts of the IEEE 1451 standards, including those relating to wireless, have recently been approved and this smart transducer standard is illustrated with several wired and wireless network examples.
Abstract: The expansion of smart sensors usage is being slowed by the lack of a universal standard, especially in the wireless area. Recognizing that no single sensor bus or network is likely to dominate in the foreseeable future, the IEEE 1451 set of standards was developed to unify the diverse standards and protocols by providing a base protocol. One feature of the IEEE 1451.0 open standard is that the data and TEDS of all transducers are communicated on the network (Internet) with the same format for all sensors and actuators for both wired and wireless networks. The development of the main parts of the IEEE 1451 standards, including those relating to wireless, have recently been approved. This smart transducer standard is illustrated with several wired and wireless network examples.

21 citations


Proceedings ArticleDOI
05 Nov 2007
TL;DR: Some relevant open standards that can help to achieve seamless sensor connections, integration, discovery, access, and usage within and across systems, networks, and enterprises through the Web are examined.
Abstract: Distributed sensor networks are emerging technology for building applications in control and condition monitoring of equipment and machinery in government and industry. Open sensor interfaces, standard sensor data formats, and messaging standards are needed to enable the integration, access, fusion, use, and delivery of sensor-derived data for these applications. The sensor standards harmonization working group was formed at NIST to address these types of issues. This paper examines some relevant open standards that can help to achieve seamless sensor connections, integration, discovery, access, and usage within and across systems, networks, and enterprises through the Web.

16 citations


Proceedings ArticleDOI
05 Nov 2007
TL;DR: An environment to achieve these goals is described and its use as a resource for Boeing and its suppliers in defining the requirements and architecture for embedding health ready systems/ subsystems in new and legacy products is described.
Abstract: As the cost and complexity of components and systems increases, more reliance is placed on IVHM systems to extend functional life and to allow repairs to maximize affordability. Successful deployment of Integrated Vehicle Health Management capabilities depends on a sound business case. From the Boeing viewpoint as a systems integrator, a major deployment obstacle is the integration of health technology into the platform avionics. Deploying effective, affordable and supportable health management systems for new or legacy aircraft must leverage the system and subsystem suppliers as well as the systems integrator. To better facilitate this integration, Boeing's Phantom Works is defining the requirements and architecture to embed 'health ready' systems and subsystems in new and legacy products. The term health ready implies an involvement and contribution by the suppliers and partners to design and build in the features needed at the system or subsystem level to achieve an overall cost effective Integrated Vehicle Health Management (IVHM) solution. This paper addresses the issues related to embedding and enabling IVHM within subsystem/system and within the overall platform avionics architecture. This includes the life cycle support of the IVHM system as well as the initial implementation. This paper describes an environment to achieve these goals and its use as a resource for Boeing and its suppliers in defining the requirements and architecture for embedding health ready systems/ subsystems in new and legacy products.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: The technology behind cabled PCI express, as well as current and future application needs in measurement and automation systems, are examined.
Abstract: The PCI special interest group (PCI-SIG), developers of the PCI and PCI express specifications, released the PCI express external cabling 1.0 specification in February 2007 to extend PCI express "outside the box." Cabled PCI express is a high-performance cabled serial bus to interconnect system components. The following sections examine the technology behind cabled PCI express, as well as current and future application needs in measurement and automation systems.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: Here, the boundary between synthetic instruments (SI) and software defined radios (SDR) becomes very thin indeed, and the SI is asked to become a smart SDR, performing all the tasks of a DSP radio receiver and reporting small variations between the observed modulated signal parameters and those of an idealmodulated signal.
Abstract: Synthetic Instruments use the substantial signal processing assets of a field programmable gate array (FPGA) to perform the multiple tasks of targeted digital signal processing (DSP) based instruments. The signal conditioning common to many instruments includes analog spectral translation, filtering, and gain control to align the bandwidth and dynamic range of the input signal to the bandwidth and dynamic range capabilities of the A-to-D converter (ADC) which moves the signal from the analog domain to the sampled data domain. Once in the sampled data domain, the signal processing performed by the FPGA includes digital spectral translation, filtering, and gain control to perform its chartered DSP tasks. A common DSP task is spectral analysis from which frequency dependent (i.e., spectral) amplitude and phase is extracted from an input time signal. Another high interest DSP task is vector signal analysis from which time dependent (i.e., temporal) amplitude and phase is extracted from the input time signal. With access to the time varying amplitude-phase profiles of the input signal, the vector signal analyzer can present many of the quality measures of a modulation process. These include estimates of undesired attributes such as modulator distortion, phase noise, clock-jitter, l-Q imbalance, inter-symbol interference, and others. Here, the boundary between synthetic instruments (SI) and software defined radios (SDR) becomes very thin indeed. Essentially this is where the SI is asked to become a smart SDR, performing all the tasks of a DSP radio receiver and reporting small variations between the observed modulated signal parameters and those of an ideal modulated signal. Various quality measures (e.g., the size of errors) have value in qualifying and probing performance boundaries of communication systems.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: This paper presents several practical modeling and reasoning considerations that have been addressed based on experience with avionics systems, including the problem of intermittent faults, handling test alarms, dealing with limited computational resources, and model reduction for large scale systems.
Abstract: Timed failure propagation graphs (TFPG) are causal models that capture the temporal aspects of failure propagation in dynamic systems. In this paper we present several practical modeling and reasoning considerations that have been addressed based on experience with avionics systems. These include the problem of intermittent faults, handling test alarms, dealing with limited computational resources, and model reduction for large scale systems.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: The current efforts by the SCC20 Diagnostic and Maintenance Control subcommittee to integrate data from a wide range of sources into a "picture" of the diagnostic and maintenance state of a system are described.
Abstract: There is no doubt that system complexity is increasing. There are a number of ramifications of this increase in complexity, besides higher performance. On one hand conventional means of testing are being overwhelmed by the complexity. On the other there are more sources of information about the system. System data is fragmented by time and discipline. Early design data is not available during the operational phase. Design data is often segregated from test data. Even within a particular discipline, e.g. diagnostics, data is fragmented. Few diagnostic reasoners can exchange data. One approach to dealing with the complexity issues is to integrate these sources of information into a single picture of the state of the system. This is the approach taken by the SCC20 Diagnostic and Maintenance Control (DMC) subcommittee. The DMC is developing a family of standards that are product information exchange standards for test, diagnosis, and maintenance. This paper describes the current efforts by the DMC to integrate data from a wide range of sources into a "picture" of the diagnostic and maintenance state of a system.

Proceedings ArticleDOI
Li Feng1, Sheng Zhuang1
05 Nov 2007
TL;DR: The background, features, and implementation details of the action-driven automation test framework designed to primarily increase the efficiency and flexibility in composing test cases and simplify the process of learning the test cases are described.
Abstract: In this paper we describe the design and implementation of an action-driven automation test framework especially for GUI software testing. The idea of action-driven automation test framework comes from the core concept of "quality assurance (QA)". Better quality can be ensured by increasing the coverage of test cases on the software but the process of creating large number of test cases has to be optimized. With this goal the framework was designed to primarily increase the efficiency and flexibility in composing test cases and simplify the process of learning the test cases. This paper describes the background, features, and implementation details of the framework.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: Failure of monitored I/O pins on operational, fully-programmed FPGAs is reported by SJ BIST and SJ Monitor to provide positive indication of damage to one or more I/o solder-joint networks of an FPGA on an electronic digital board.
Abstract: An update on a method (SJ BISTtrade) to detect intermittencies in Ball Grid Array (BGA) packages is presented, and another method (SJ Monitortrade) is introduced. SJ BISTtrade is primarily firmware embedded in the FPGA application; SJ Monitortrade is hardware on an IC chip. Failure of monitored I/O pins on operational, fully-programmed FPGAs is reported by SJ BIST and SJ Monitor to provide positive indication of damage to one or more I/O solder-joint networks of an FPGA on an electronic digital board. The board can then be replaced before accumulated fatigue damage results in intermittent or long-lasting operational faults.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: In order to achieve high levels of reusability and flexibility, an object-oriented meta-model of the parallel TPS is presented, described with Unified Modeling Language (UML).
Abstract: Parallel test is a new direction for the future automatic test systems (ATS) to reduce test time and costs of the increasingly complex and time-consuming Units-Under-Test (UUTs) test. It is also one of the key technologies of the DOD's "NxTest". In fact, future ATSs must provide some parallel testing features so as to have unparalleled performance. The kernel of the Parallel ATS is Parallel TPS. At present, there are no practical architectural models or patterns for the parallel TPS's R&D. This paper introduces the parallel TPS's analysis, design and application based on software architecture, components and patterns. A brief discussion of the parallel ATS's architecture and system requirements are provided. In order to achieve high levels of reusability and flexibility, an object-oriented meta-model of the parallel TPS is presented, described with Unified Modeling Language (UML). The layered component-based framework of the Parallel TPS is designed based on that meta-model. The framework makes full uses of the design patterns and is more likely to achieve reliability and extendibility. Based on such a framework and design patterns, not only can the parallel TPS reuse both its design architecture and source code, but also can be developed more efficiently and easier to maintain and extend.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: This paper proposes a novel signal processing front end for fast Fourier transform(FFT)-based spectrum analyzers and shows how employing polynomial-based filtering structures leads to more efficient solutions than were previously available.
Abstract: In this paper we propose a novel signal processing front end for fast Fourier transform(FFT)-based spectrum analyzers. Recent developments in polynomial-based filtering have yielded efficient structures for sample rate reduction by arbitrary factors. This is a key operation in FFT-based spectral analysis when arbitrary span capability is required. It is shown how employing these structures leads to more efficient solutions than were previously available.

Proceedings ArticleDOI
C. Proft1
05 Nov 2007
TL;DR: This paper will illustrate and demonstrate how test system challenges are being addressed with existing GPIB and LXI class C instruments and how class A and B instruments will provide exciting new test system capabilities.
Abstract: With over 320 LXI instruments available in a little more than two years, electronic functional and data acquisition test systems can now be implemented with LXI instruments from a wide variety of product categories. Test system builders are often interested in three major areas: reduced system complexity with easier configuration, lower system cost, and increased performance. LXI instruments score high in lowering cost, remote access, and being easier to configure, verify, and debug, but there is discussion over performance in the area of latency and throughput. LXI class A and B instrumentation provide new test system techniques through flexible triggering schemes such as LAN messaging, IEEE-1588 timing, and downloaded scripts. While most LXI instruments are currently class C and are targeted to replace GPIB equivalents, 2007 and 2008 will see an increase of class A and B instruments that provide new and exciting possibilities that can directly improve performance and reduce system complexity. This paper will illustrate and demonstrate how test system challenges are being addressed with existing GPIB and LXI class C instruments and how class A and B instruments will provide exciting new test system capabilities.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: In this paper, an obsolescence assessment of the US Army's Integrated Family of Test Equipment (IFTE) functional test cards revealed a very serious problem and an Obsolescence Working Group (OWG) was formed to identify, recommend, and initiate corrective actions.
Abstract: The US Army Aviation and Missile Research, Development, and Engineering Center (AMRDEC) Engineering Support (ES) Division and the Integrated Materiel Management Center (IMMC), located on Redstone Arsenal, Alabama, have undertaken an enormous task of mitigation and management of obsolescence in the Army's Integrated Family of Test Equipment (IFTE). The team of the ES Division and the co-located IMMC logistics cell provides total life-cycle engineering and logistics management and support of diagnostics, prognostics, test equipment, and systems for aviation, missile, and other Department of Defense and government agencies in support of the warfighter. The IFTE family of test equipment includes the Base Shop Test Facility (BSTF), the Commercial Equivalent Equipment (CEE), the Electro-Optics Test Facility, and the Next Generation Automatic Test System. The basic mission of the IFTE is to support the testing of electronic and electro-optic weapons devices. In 2004 an obsolescence assessment of the IFTE BSTF functional test cards revealed a very serious problem. The IFTE BSTF was found to have a large percentage of microelectronic obsolescence. In order to address this issue, an Obsolescence Working Group (OWG) was formed to identify, recommend, and initiate corrective actions. The OWG identified several options for mitigating the obsolescence issues with the IFTE BSTF. Cost comparisons were performed for each of the options. Although most of the options appeared feasible and economical, funding was not available to support any of them. The OWG initiated actions to obtain funding through Army cost savings and reliability improvement programs.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: This paper will show how diagnostic reasoner technology can be used in the automated test industry and describe some issues and lessons learned while integrating with legacy components and provide some recommendations to be considered when designing new test systems and TPSs.
Abstract: This paper will show how diagnostic reasoner technology can be used in the automated test industry. It will briefly explain how diagnostic reasoners can reduce overall logistics support costs by reducing test time and more accurately identifying failed components. It is believed that diagnostic reasoner technology can be applied to both new and legacy test program sets (TPSs) and test systems. The paper will describe some issues and lessons learned while integrating with legacy components and will provide some recommendations that should be considered when designing new test systems and TPSs.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: This article describes the eight schemas that make up ATML and focuses on the test description and test results schemas to demonstrate how ATSs can use these components.
Abstract: Although ATML has started to gain momentum in the defense industry because of its adoption in high-profile projects (Woodward and Harris, 2006) and its implementation by ATS vendors (Gonzalez, 2006), a large segment of the automatic test community lacks in-depth knowledge of all the ATML components and how to use ATML in their own systems. Furthermore, for ATML to deliver on the productivity gains it proposes, ATML must be adopted beyond the defense industry. This article is an introduction to ATML, its subcomponents, and how it is being used in automatic test software development. In particular, this article focuses on how ATML can facilitate information exchange, expand interoperability of test systems, and increase ATS component documentation. The article describes the eight schemas that make up ATML and focuses on the test description and test results schemas to demonstrate how ATSs can use these components.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: In this article, the authors propose a needed evolution in automated satellite testing for both government and commercial mission applications and discuss roles and contributions by the U.S. government, commercial satellite services, the satellite manufacturers, and the automated test industry.
Abstract: This paper proposes a needed evolution in automated satellite testing for both government and commercial mission applications. Roles and contributions by the U.S. government, commercial satellite services, the satellite manufacturers, and the automated test industry are discussed. Specific areas with identifiable return on investment are presented as a starting point on a long term path for applying current industrial automation to the satellite test sector.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: The paper leads the user through a simple set of increasingly complex problems, at each step describing instrument and test system capabilities in a standard and reusable manner, and shows how real world complex systems can be described though a methodical and consistent process.
Abstract: This paper describes the major concepts of ATML Capabilities and how they are used to describe instrument performance and capabilities, using simple examples and use cases. The paper leads the user through a simple set of increasingly complex problems, at each step describing instrument and test system capabilities in a standard and reusable manner. The paper takes the form of a tutorial, posing and solving increasingly complex instrument description capabilities, with each step clearly explained and defined. Each step concentrates on a particular feature of the ATML capability standard, and each step shows how real world complex systems can be described though a methodical and consistent process. Finally the paper considers the impact that ATML capabilities could have on the test industry as a whole, and offers some real and tangible benefits that may be achieved by the adoption of ATML capabilities by the industry as a whole.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: The objective is to analyze the development effort required by a TPS engineer to produce a Test Program from scratch using only the elements provided by the IEEE 1641 Standard.
Abstract: The IEEE 1641 STD standard, provides a new way to define test requirements independently of the language and test station platform. Initiatives to put the standard into practice to discover its applicability to industry have been taken. The present study is concerned with this initiative. The objective is to analyze the development effort required by a TPS engineer to produce a Test Program from scratch using only the elements provided by the IEEE 1641 Standard. The study covers the description of test requirements based on the IEEE 1641 constructs to its implementation and execution in a real ATE (the SAMe ATE by Indra Sistemas). The development of a test program applying this standard implies the definition of a new methodology compared to the one traditionally used in the organization. The implementation of the test program brings out the issue of which programming environment to use, and the tools to support the process. The execution of the test program suggests the development of a 1641 compliant run-time system (RTS), so that the test program generated directly uses the elements defined by the standard (BSC's and TSF's) to implement the test requirements.

Proceedings ArticleDOI
A. Scott1
05 Nov 2007
TL;DR: In this paper, a theoretical framework and algorithmic methodology for obtaining useful diagnostic and prognostic data from electro-mechanical systems was developed based on vibration and modal analyses of the physical components.
Abstract: In support of the Condition Based Maintenance (CBM) philosophy, a theoretical framework and algorithmic methodology for obtaining useful diagnostic and prognostic data from electro-mechanical systems was developed. The methods are based on vibration and modal analyses of the physical components. To illustrate the concept of the derived process, two "real world" models, a PCI circuit card, and an example rotor hub were considered. Models were created using finite element analysis (FEA) techniques, and analyzed to determine fundamental mode shapes and vibration frequencies. Simulations were initially conducted on unadulterated benchmark models, and then faults common to the actual physical components were introduced to the models for subsequent simulation. The results yielded vibration modes characteristic of both undamaged and damaged systems. The obtained system natural frequencies for each FAULT test signal vector were compared to the NORMAL operation benchmark signal. An O(N*logN) correlation technique was utilized for signal discrimination. Application of the developed techniques proved very useful, and correctly identified all inserted FAULTS on the simulated systems.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: In this paper, the concept of design for diagnosability (DfD) is introduced as a different concept than design for testability, which enables circuit designers to distinguish between those guidelines that separate good circuits from faulty ones and guidelines that are aimed at improving the repair process.
Abstract: The concept of design for diagnosability (DfD) is introduced as a different concept than design for testability (DfT). Separating design for diagnosability guidelines from those of the more general design for testability guidelines enables circuit designers to distinguish between those guidelines that separate good circuits from faulty ones and guidelines that are aimed at improving the repair process. Comprehensive fault detection does not result in cost effective repair without unambiguous fault isolation. A model is used to demonstrate the distinctions between test and diagnostic goals. Diagnoses related terminology is introduced and diagnostic complications are discussed. Hidden faults, cannot duplicates (CNDs), retest OK, fault isolation ambiguity, false remedies and false alarms are explored in great detail. A Venn diagram model is used to further explain Diagnosability and the diagnostic complications. The term Distinguishability is added to our vocabulary as the positive dual of ambiguity. The paper probes the possible causes of the various diagnostic issues and provides guidelines designers can incorporate to eliminate them. The paper offers specific design guidelines to achieve a more diagnosable or diagnostic-friendly circuit design. In doing so, diagnostic complications can be reduced, resulting in lower cost repairs and maintenance.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: The 'circuit as a sensor' concept as an innovative and practical PHM solution for electronic systems through proof of concept using radio frequency digital (RF/D) systems and is scalable and can be applied to broad class of electronic systems.
Abstract: The maintainability and reliability of critical electronic systems such as radars and global positioning system (GPS) on military and commercial aircrafts is a significant concern. Practical condition assessment and prediction of remaining useful life for such systems offer significant potential for improved readiness and field reliability. This paper introduces the 'circuit as a sensor' concept as an innovative and practical PHM solution for electronic systems through proof of concept using radio frequency digital (RF/D) systems. To demonstrate the feasibility of this concept, an economical test platform operating in the frequency range representative of modern avionic systems, with available system and component features was selected. An experiment to study the effects of degradation from the highly accelerated tests on diagnostic features as well as derive failure progression trends was conducted. Results from this research are presented. The embedded diagnostic and prognostic capability developed is scalable and can be applied to broad class of electronic systems.

Proceedings ArticleDOI
05 Nov 2007
TL;DR: Cabled PCI Express technology is being used as method for remote VXI control while PXI has integrated PCI Express signaling into the backplane.
Abstract: This paper discusses the advantages and benefits of PCI Express technology. As a dedicated high bandwidth, low latency bus, PCI Express possesses specific technical advantages for test and measurement applications. This paper examines some specific examples of how PCI Express has been applied to existing standards like PXI and VXI. Cabled PCI Express technology is being used as method for remote VXI control while PXI has integrated PCI Express signaling into the backplane. This document also discusses the benefits of cabled PCI Express and its role in synthetic instrumentation systems. As a low latency, high bandwidth bus, PCI Express provides many technical advantages for the test and measurement industry.