Showing papers presented at "AUTOTESTCON in 1992"
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21 Sep 1992
TL;DR: Infrared thermal images, captured during the initial warmup of an electronic circuit card, are employed to enhance the available information and to assist the technician in performing the fault diagnosis.
Abstract: In many instances, the electronic state of an electronic circuit card contains insufficient information for correct fault diagnosis Infrared thermal images, captured during the initial warmup of an electronic circuit card, are employed to enhance the available information and to assist the technician in performing the fault diagnosis This system has proven beneficial for radar and microwave technologies where probing changes the electronic response of the circuit and signal levels can be extremely small The development of this system has required the integration of technologies from a diversity of fields including image capture, image compression, image enhancement, neural networks, genetic algorithms, thermodynamics, and automatic test equipment (ATE) software These technologies and preliminary system performance are discussed >
23Â citations
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21 Sep 1992TL;DR: In this paper, the authors describe a vision of unambiguous fault isolation on RF equipment and enabling critical technologies, and the overall goal is reduction of logistic support and maintenance cost of RF subsystems.
Abstract: The authors describe a vision of unambiguous fault isolation on RF equipment and enabling critical technologies. The overall goal is reduction of logistic support and maintenance cost of RF subsystems. Savings will be achieved through reduced false alarms, troubleshooting, false removal rates, spares inventory, and support equipment. The authors describe technology developments in miniature sources and signal analyzers with examples of built-in test (BIT) implementations utilizing specifically designed monolithic microwave integrated circuits (MMICs). These emerging technologies applied to integrated diagnostics can result in substantial cost avoidance in maintenance, spares inventory, and support equipment. >
8Â citations
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21 Sep 1992TL;DR: The author discusses an approach to identifying and correcting errors in diagnostic models using explanation based learning that uses a structural model or information flow model to guide diagnosis.
Abstract: The author discusses an approach to identifying and correcting errors in diagnostic models using explanation based learning. The approach uses a model of the system to be diagnosed that may have missing information about the relationships between tests and possible diagnoses. In particular, he uses a structural model or information flow model to guide diagnosis. When misdiagnosis occurs, the model is used to determine how to search for the actual fault through additional testing. When the fault is identified, an explanation is constructed from the original misdiagnosis and the model is modified to compensate for the incorrect behavior of the system. >
8Â citations
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12 May 1992
TL;DR: In this article, a means for automating knowledge acquisition and integrating it into the design process, and presents NASA's CAD/CAE knowledge base development tool (KBDT) as a prototype for demonstrating the concept of automated knowledge acquisition.
Abstract: The author discusses how knowledge acquisition will become a key element to improving the design, production, and testing of complex electronic, mechanical, and hydraulic systems. Specifically, knowledge acquisition will become critical to the use of dependency model systems. The author also discusses a means for automating knowledge acquisition and integrating it into the design process, and presents NASA's CAD/CAE knowledge base development tool (KBDT) as a prototype for demonstrating the concept of automated knowledge acquisition. KBDT's basic structure, its operation, and its integration with NASA's knowledge-based autonomous test engineer (KATE), are described. KBDT's unique combination of voice synthesis, voice recognition, natural language processing, and knowledge acquisition processing components, integrated via a blackboard architecture, necessary for this knowledge engineering application, are outlined. >
7Â citations
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21 Sep 1992
TL;DR: The author describes integrated system architectures and the requirements imposed on an RF system for an advanced platform and explains the evolution of an architecture which can meet those requirements.
Abstract: Emerging built-in test requirements for electronic warfare systems on platforms such as the F22 advanced tactical fighter necessitate advanced techniques to cost-effectively detect, isolate, and report RF faults. The author describes integrated system architectures and the requirements imposed on an RF system for an advanced platform and explains the evolution of an architecture which can meet those requirements. Diagnostic false alarm reduction is discussed, with analogies to false alarm reduction in the target detection domain. The problem of aperture testing is discussed, and a description of how these RF assets can interact with Depot test equipment is given. >
6Â citations
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21 Sep 1992TL;DR: An approach to associating temporal knowledge with a diagnostic system using an interval based approach, but incorporating point intervals in the model, and a propositional calculus representation of the temporal relations derived and combined with the transitive closure algorithm that operates on a bit matrix.
Abstract: The authors describe an approach to associating temporal knowledge with a diagnostic system They present a summary of work done in developing an algebra of relations for temporal reasoning, and proceed to extend the work using an interval based approach, but incorporating point intervals in the model A propositional calculus representation of the temporal relations is derived and combined with the transitive closure algorithm that operates on a bit matrix The result is an efficient and relatively simple approach to modeling relations between temporal intervals and propagating the constraints imposed by these relations through the knowledge base >
5Â citations
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21 Sep 1992TL;DR: The authors investigate the modeling of discrete event systems in a distributed context, as well as problems of a nature related to the mapping of a simulation onto a parallel or distributed architecture.
Abstract: The research approach presented focuses on the investigation of real-time distributed (RTD) systems development and simulation. The authors are developing a formalized simulation method for performance modeling and analysis of RTD systems. In more specific terms, a system model is defined as an abstraction of the RTD system, which consists of both a conceptual and physical model. The conceptual model controls activities which sense and control the dynamics of the functional description, while the physical model defines the structural architecture. The behavioral model is the visible part of the system which displays how the reactive and dynamic activities of the system are affected by different simulated environmental stresses. The authors investigate the modeling of discrete event systems in a distributed context, as well as problems of a nature related to the mapping of a simulation onto a parallel or distributed architecture. >
5Â citations
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21 Sep 1992
TL;DR: The author presents a cohesive set of heuristic algorithms that can be used with boundary-scan logic to diagnose interconnect faults to create a well-thought-out test generator which meets the outlined requirements.
Abstract: The author presents a cohesive set of heuristic algorithms that can be used with boundary-scan logic to diagnose interconnect faults The terms that are used, a brief overview of the boundary-scan architecture, and the boundary-scan test generator requirements are given The interconnect diagnostics and the heuristic algorithms that are used during the processing are discussed A well-thought-out test generator which meets the outlined requirements is essential The diagnostic program performs best when it acquires as much information as it can during initialization >
4Â citations
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21 Sep 1992
TL;DR: An object-oriented graphical user interface TPS-X is described, which provides the test program set (TPS) designer with a development tool that is independent of the automated test equipment (ATE) and the programming language used by the ATE.
Abstract: The authors describe an object-oriented graphical user interface TPS-X, which provides the test program set (TPS) designer with a development tool that is independent of the automated test equipment (ATE) and the programming language used by the ATE. The interface uses object-oriented symbols representing test objects and circuit topology to show the test strategy as opposed to using a specific language syntax. A TPS-X graphical test diagram and the resulting TPS may be transported from a software development system to and between various test stations. This method of TPS development also aids the TPS debug and maintenance effort by providing a simple visual description of the test strategy and a method of updating the description as opposed to studying source code to determine the strategy and where to make the necessary changes. >
4Â citations
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21 Sep 1992
TL;DR: McDonnell Aircraft Company has implemented improved procedures and developed new CAE tools to enhance the supportability of the new and modified equipment under development for the F/A-18E/F program as discussed by the authors.
Abstract: McDonnell Aircraft Company has implemented improved procedures and developed new CAE tools to enhance the supportability of the new and modified equipment under development for the F/A-18E/F program These procedures and tools were designed to reduce or eliminate support equipment requirements, ensure compatibility with automatic test equipment, and enhance equipment testability and thereby reduce life cycle cost associated with support and maintenance of the airborne equipment This will be accomplished by emphasizing testability and other diagnostic elements through the implementation of an extended interorganizational concurrent engineering environment The development and application of an automated testability analysis tool (AutoTEST) are discussed AutoTEST can perform an analysis with varying levels of component and circuit detail AutoTEST supports both a top-down and a bottom-up analysis approach The tool will also be used to integrate the various functions and organizations involved in the product development process >
3Â citations
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21 Sep 1992
TL;DR: Results indicate that neural networks can generalize around the data on which they were trained, yielding better performance for unforeseen inputs than traditional algorithms in the case of the fault diagnosis problem described.
Abstract: A neural network based fault diagnosis system is being developed for use in aerospace systems in which a family of neural nets replaces an online simulation process A new neural network implementation of one of the model-based algorithms was developed The authors summarize a series of computer experiments designed to benchmark the performance of this neural network based fault diagnosis algorithm in an environment where the good components of the systems are only known up to a tolerance band The results indicate that neural networks can generalize around the data on which they were trained, yielding better performance for unforeseen inputs than traditional algorithms in the case of the fault diagnosis problem described >
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21 Sep 1992
TL;DR: Neural network technology is considered that may significantly reduce the time required to obtain steady-state compressor maps using neural networks trained to learn correlations between transient and steady- state compressor performance.
Abstract: Neural network technology is considered that may significantly reduce the time required to obtain steady-state compressor maps. This reduction would be accomplished using neural networks trained to learn correlations between transient and steady-state compressor performance. Neural networks that generalize with guaranteed bounds on computational effort, smoothness, and stability are particularly appropriate for this application. The learned correlation could make important contributions to the solution of stall recovery and surge anticipation problems. >
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21 Sep 1992
TL;DR: In this article, an interim status report on the implementation of a company wide continuous quality improvement (CQI) total quality management (TQM) initiative dealing with cost, technology, and organizational problems associated with development and transfer of electronics/avionics test strategies from prime equipment design to manufacturing test and subsequently to depot level maintenance is presented.
Abstract: This study is an interim status report on implementation of a company wide continuous quality improvement (CQI) total quality management (TQM) initiative dealing with cost, technology, and organizational problems associated with development and transfer of electronics/avionics test strategies from prime equipment design to manufacturing test and subsequently to depot level maintenance. This interim status report highlights the concerns, problems, and tentative solutions to implementing a company wide common automated test equipment (ATE) architecture for commercial airlines and for military programs. >
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21 Sep 1992
TL;DR: In this article, the authors describe the general principles underlying the testability analysis of analog circuits and systems performed by the automated testability expert system tool (AutoTEST) which is an artificial intelligence (AI) based CAE tool.
Abstract: Increasing avionic design complexities and diagnostic requirements have focused attention on the need for performing a testability analysis early in the design cycle. The author describes the general principles underlying the testability analysis of analog circuits and systems performed by the automated testability expert system tool (AutoTEST) which is an artificial intelligence (AI) based CAE tool. The goal is to perform a testability analysis early in the design cycle to ensure conformance with diagnostic requirements. To meet this goal, AutoTEST was designed to perform an analysis with varying levels of component and circuit detail. AutoTEST supports both a top-down and a bottom-up approach. The analog and system level portions of AutoTEST provide test and design engineers with both quantitative measures and qualitative descriptions of the testability of a given design. Quantitative measures are testability figures of merit such as fraction of faults detected, fault isolation resolution, and average ambiguity group size. Qualitative descriptions of testability problems include identifying feedback loops and unique circuit configurations which are difficult to test. The qualitative analysis consists of a set of design rules that are applied to the circuit. At the completion of an AutoTEST session, selected analysis results are written to a set of report files. >
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21 Sep 1992
TL;DR: The portable electrooptics tester (PET) as mentioned in this paper is a small, man-portable field forward-looking IR (FLIR) MRTD test system that can accurately measure multiple spatial frequency minimum resolvable temperatures (MRTs) within minutes of power application.
Abstract: A key performance parameter of thermal imaging systems is the minimum resolvable temperature difference (MRTD). The authors describe a new approach to on-platform end-to-end thermal imaging system testing which can be accomplished in an unstable field environment, and application of the technique to a superior cost effective field MRTD test system. The new approach consists of quickly establishing the system radiometric zero and very accurately referencing all blackbody temperatures to the radiometric zero. This approach provides excellent radiometric control, resolution, stability, and speed that are needed for meaningful field testing of thermal imaging systems. A test system which incorporates the technology, the portable electrooptics tester (PET), is a small, man-portable field forward-looking IR (FLIR) MRTD test system. The PET was designed to accurately measure multiple spatial frequency minimum resolvable temperatures (MRTs) within minutes of power application. A novel technique is also used to determine if the thermal imaging system under test is mission capable, even if it is not performing to its design specification. >
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21 Sep 1992TL;DR: A knowledge-based approach for diagnosis of electronic circuits in avionics systems is discussed and a generally-applicable shell incorporating the methodology was developed in a commercial software package and applied to the development of a diagnostic system for a black and white television circuit.
Abstract: A knowledge-based approach for diagnosis of electronic circuits in avionics systems is discussed. The knowledge-based methodology is generic and was designed for accurate and efficient identification of malfunctioning circuit components in diagnostic situations involving single-component malfunctions, multiple independent malfunctions, and multiple interacting malfunctions. The resulting methodology integrates the features of two knowledge-based techniques. Hierarchical classification (HC), a compiled knowledge approach, is used to efficiently identify single and multiple malfunctions. An approach called diagnostically focused simulation, which refines the HC results with causal reasoning, is then used to resolve whether multiple malfunctions are the result of independent component failures or whether an interaction exists that relates the malfunction behaviors. A generally-applicable shell incorporating the methodology was developed in a commercial software package and applied to the development of a diagnostic system for a black and white television circuit. >
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21 Sep 1992
TL;DR: In this paper, the authors focus more on the factors that govern the integrated design rather than on the design itself, and the experience on this program suggests that concurrent engineering should be implemented from the viewpoint of specifying system requirements that force the process.
Abstract: Vertical test equipment commonality implemented in support of two level maintenance for the Army TACMS missile led to a concurrently engineered development program. The customer prime contractor and subcontractors united as a team in pursuing an integrated concurrent design. The author concentrates more on the factors that govern the integrated design rather than on the design itself. A brief description of the system and then a little more detail on the influence of commonality on design approach, concept, and requirements serve as a backdrop for a discussion on personnel interaction and lessons learned. The expected benefits of lower test equipment costs, improved quality, and mature organic depot support at initial operational capability (IOC) were all realized. The experience on this program suggests that concurrent engineering should be implemented from the viewpoint of specifying system requirements that force the process. >
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21 Sep 1992TL;DR: In this article, a consolidated automated support system (CASS) electrooptic (EO) configuration eliminates the need for dedicated laser transmitter testers using state-of-the-art instrumentation, CASS has the ability to determine laser energy and far-field spatial characteristics.
Abstract: The majority of laser target designators in the current military inventory are 1064- mu m, Q-switched, Nd:YAG laser transmitters In addition to its capabilities for forward looking infrared (FLIR) and camera testing, the consolidated automated support system (CASS) electrooptic (EO) configuration eliminates the need for dedicated laser transmitter testers Using state-of-the-art instrumentation, CASS has the ability to determine laser energy and far-field spatial characteristics that include alignment, peak power, pulse energy, energy distribution, beam divergence, satellite beam measurements, and pulse period All these tests are performed under ATLAS test programming language control >
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21 Sep 1992
TL;DR: The authors provide more background on ABET standardization and describe recent ATAG accomplishments and current plans to develop needed draft standards, and provide data needed to address some significant open areas in the current drafts.
Abstract: For the past two years, the Ada Based Environment for Test (ABET) Technical Advisory Group (ATAG) has been working to expedite development of the IEEE ABET standards. J.E. Heiser and K. Schoonover (1991) discussed the formation, structure, and early results of the USAF ATAG initiative. The authors provide more background on ABET standardization and describe recent ATAG accomplishments and current plans. The drafts and reports produced by the ATAG during this second year have significantly aided evolution of the ABET family of standards. Proposed tasks will develop needed draft standards, and provide data needed to address some significant open areas in the current drafts. >
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21 Sep 1992TL;DR: A systems modeling approach was applied to the (Boeing 747-400 airplane) to study its effectiveness in accurately representing various on-board systems and analyzing their failure detection, isolation, and propagation.
Abstract: The authors describe a systems modeling approach for design and analysis of failure prevention, detection, and isolation The modeling approach was applied to the (Boeing 747-400 airplane) to study its effectiveness in accurately representing various on-board systems and analyzing their failure detection, isolation, and propagation The modeling approach is based on use of state transition diagrams as well as functional and information flow diagrams The model presented, which is executable and testable, includes the Boeing 747-400 electrical power generation and distribution system, the communications system, the central maintenance system, and the user interface system for interaction with the crew Results of failures injected in the model for analysis of various scenarios are presented >
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21 Sep 1992
TL;DR: The author discusses artificial intelligence (AI) applications for the human interface of the test/diagnosis environment, which can contain speech recognition, understanding, and response and visual perception of thetest environment.
Abstract: The author discusses artificial intelligence (AI) applications for the human interface of the test/diagnosis environment. The human interface can contain speech recognition, understanding, and response and visual perception of the test environment. The areas of focus for the human interface are described. The intelligent diagnostic functions available at the human interface provide complete automated test/diagnostic data entry and evaluation to the human. The human interface of the AI system is a multimedia environment. The integrated AI system promises to facilitate ease in long term support. This is accomplished by moving the information domain into a user-oriented configuration. What specifically happened to a unit when it failed will determine the repair action. Expert know-how will reside in a usable knowledge sharing domain. Arbitrary testing-diagnosing philosophies will no longer exist. Only the part(s) which is defective will be tested and repaired. >
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21 Sep 1992TL;DR: A standardized, comprehensive tool certification procedure was developed that has interdicted tool errors that conceivably could have caused failure in software/systems tests or allowed faulty deliverable hardware items to pass and be integrated into final systems.
Abstract: The authors describe a generic process for the certification of custom-made, user modified and off-the-shelf tools including automatic test equipment (ATE) and development tools. A standardized, comprehensive tool certification procedure was developed. This procedure includes participation with many varied groups from conception of the tool through final acceptance and its subsequent use. The major areas of the procedure are addressed. The use of this comprehensive tool certification by an independent software quality engineering group has interdicted tool errors that conceivably could have caused failure in software/systems tests or allowed faulty deliverable hardware items to pass and be integrated into final systems. The procedure also mandates correct configuration control of tool software and hardware. This procedure encourages total quality management (TQM). It has been shown to inspire better customer confidence in the test tools and the whole testing process chain. >
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21 Sep 1992TL;DR: The authors discuss the results of a proof-of-concept effort aimed at defining an automatic test equipment (ATE) architecture that incorporates both built-in-test (BIT) data and functional testing techniques.
Abstract: The authors discuss the results of a proof-of-concept effort aimed at defining an automatic test equipment (ATE) architecture that incorporates both built-in-test (BIT) data and functional testing techniques The concept, called BENeFITS (BIT-Enhanced Functional Test System), uses fault guided analysis techniques to process BIT failure data retrieved from the unit under test and perform functional testing only on the sections indicated by BIT Other features include the use of software algorithms and artificial intelligence (AI) principles to improve fault callout accuracies over time >
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21 Sep 1992TL;DR: In this paper, the electrical performance of wafer-scale integration interconnections was studied, with an emphasis on the characteristic impedance, based on closed-form expressions, finite difference method models, commercially available microwave circuit analysis software, and a numerical evaluation of the Telegrapher equations.
Abstract: The electrical performance of wafer-scale integration interconnections was studied, with an emphasis on the characteristic impedance. The study was based on closed-form expressions, finite difference method models, commercially available microwave circuit analysis software, and a numerical evaluation of the Telegrapher equations. Measurements were conducted on 5-in-diameter test wafers which contained numerous interconnection structures. The results revealed interesting information concerning the driving-point impedances of the structures, the inadequacy of closed-form models for accurate estimation, and the need for more accurate modeling techniques. >
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21 Sep 1992
TL;DR: The authors propose a new approach to evaluating AI based ATE systems under AI-ESTATE using a weighted evaluation function based upon the functional capabilities of the AI system called the functional intelligence ratio (FIR).
Abstract: Recent work by the IEEE Standards Coordinating Committee 20 (SCC-20) has included the specification of standards for artificially intelligent automatic test equipment (ATE). The SCC-20 established a subcommittee known as AI-ESTATE (artificial intelligence expert system tie to automatic test equipment). The authors propose a new approach to evaluating AI based ATE systems under AI-ESTATE using a weighted evaluation function based upon the functional capabilities of the AI system called the functional intelligence ratio (FIR). They describe the problems associated with evaluating AI systems, describe the role of AI-ESTATE as part of SCC-20, and present the FIR with a sample list of base requirements. >
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21 Sep 1992
TL;DR: The author discusses the design to test data representations that are being developed by Rome Laboratory in concert with representatives of the computer aided design/test (CAD/CAT) industry and various US Department of Defense and government agencies under the auspices of the IEEE.
Abstract: The author discusses the design to test data representations that are being developed by Rome Laboratory in concert with representatives of the computer aided design/test (CAD/CAT) industry and various US Department of Defense and government agencies under the auspices of the IEEE. Few standard representations of engineering, design, and test information exist to foster exchange and reuse in any reasonable fashion during the process of developing and fielding electronic systems. One problem is that the data generated by one vendor's tool cannot be readily used by the tools of another vendor. Another problem is that no integrated solution exists to address the complete spectrum of engineering, design, and test activities. Three industry standard data representations that are in various stages of development are presented, and their potential impact on the problem domain is examined. >
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21 Sep 1992
TL;DR: The author describes work being performed in the IEEE Standards Coordinating Committee 20 (SCC-20) P1232 committee related to the development of standards for interchange between knowledge and information sources and knowledge-based systems used in test and diagnosis applications.
Abstract: The author describes work being performed in the IEEE Standards Coordinating Committee 20 (SCC-20) P1232 committee related to the development of standards for interchange between knowledge and information sources and knowledge-based systems used in test and diagnosis applications. The goals, philosophy, and direction of the P1232 knowledge and information interface component standard, which encompasses the use of multiple ontologies and utilizes existing and currently developing standards to a large degree, is described along with the rational for the introduction, evolution, and potential benefits of this standard. Its relationship with the other P1232, SCC-20, and IEEE/ANSI standards is identified. Coordination with other knowledge-based system standards efforts in an attempt to prevent duplication and the development of diverging standards is discussed. The current status in the development of this standard, and future planned efforts for its continued development are described. >
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21 Sep 1992TL;DR: Digital signal processing (DSP) techniques, coupled with high performance digital interfaces, provide a highly flexible test set that can verify the performance of digital radar LRUs with minimum equipment and results in a downsized, highly mobile ATE which significantly reduces LRU test times.
Abstract: Testing of modern airborne radar systems requires the automated test equipment (ATE) to interface with complex microprocessor based data and memory intensive line replaceable units (LRUs) Bendix Guidance and Control Systems has, for over twenty years, been testing fire control radars Bendix recognized that a flexible/reconfigurable test set was required to minimize the development of new interfaces The authors discuss the development of a test set based on existing, non-proprietary architecture using the VXI bus The computational power of newly developed array processors produces substantial performance improvements over general purpose computers when performing floating point calculations on arrays of data Digital signal processing (DSP) techniques, coupled with high performance digital interfaces, provide a highly flexible test set that can verify the performance of digital radar LRUs with minimum equipment Implementing these techniques into a test set results in a downsized, highly mobile ATE which significantly reduces LRU test times >
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21 Sep 1992TL;DR: The authors compare and contrast the future automated diagnostic approach to the paper based methodology of today and show that enhanced maintenance performance was achieved when a diverse work force was equipped with PMAs.
Abstract: Current flight line maintenance troubleshooting uses static fault isolation trees contained in paper based technical manuals. Future troubleshooting trends will automate the flight line diagnosis of system failures using portable maintenance aides (PMAs). The authors compare and contrast the future automated diagnostic approach to the paper based methodology of today. Field experiment results are also presented that quantify the differences between these two troubleshooting approaches. These field experiments conducted at Luke Air Force Base showed that enhanced maintenance performance was achieved when a diverse work force was equipped with PMAs. >
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21 Sep 1992
TL;DR: The author cites instances where multitasking is and is not appropriate and suggests some guidelines for implementing multithreaded Ada test programs developed in conformance with ABET/ATLAS.
Abstract: The author discusses the application of tasking in Ada test programs to satisfy multithreaded dynamic functional testing requirements Ada's inherent multitasking capability, which can express both control and data dependencies among simultaneous actions, is one of the reasons why the IEEE ATLAS Committee (SCC 20) is presently engaged in developing a new Ada-based test program specification standard, designated informally as ABET/ATLAS Experience using ATLAS tasking can be applied in the development of the ABET standards and in the implementation of Ada test programs The author cites instances where multitasking is and is not appropriate and suggests some guidelines for implementing multithreaded Ada test programs developed in conformance with ABET/ATLAS >