Showing papers presented at "AUTOTESTCON in 1978"

Commercial applications of ate

Abstract: The need for custom designed Automatic Test Equipment (ATE) for production testing of high volume commercial and consumer electronics is explored. Topics discussed include economic rationale, hardware and software design considerations, hardware interface, operator interface as well as the relationship between the ATE supplier and his customers.

A review of analog automatic test generation

Abstract: Analog automatic test generation techniques are classified by the method of fault isolation utilized in implementation. These are fault analysis and fault dictionary, and are similar to the two branches of sta tistical inference: estimation (of actual network ele ment values from terminal measurements)'and hypoth esis testing (deciding which network element values have drifted out of tolerance), respectively. The clas ses also identify where in the fault isolation cycle com puter simulation takes place: fault analysis implies simulation after testing on the automatic test equip ment, whereas fault dictionary implies simulation prior to testing. Fault isolation methods known to be under investigation are discussed.

Software techniques for a microprocessor-based data acquisition device

Abstract: A Vehicle Monitoring System (VMS) based on the RCA 1802 microprocessor, was de veloped for recording the use, condi tion, and maintenance action experienced by military vehicles in their day-to-day operation. Data are collected over a period of up to one month by an unat tended on-board monitoring unit and are stored in a highly compacted digital form for later analysis. A multi-task ing operating system enables the real time monitoring of 18 digital and 25 analog parameters. Data predefined as "non-significant" are discarded, while significant data are saved in a 15-k byte storage area in the form of both detailed profiles and summary indicators and histograms. Retrieval of data is accomplished through the use of an off board cassette unit which can also be used to modify the control software of the monitoring unit. The data can then be analyzed by an off-line computer system to extract information relating to vehicle design and performance, effectiveness of maintenance programs, and causes or precursors of vehicle component failures.

Requirements communication

Abstract: Accurate requirements communication is critical to effective functioning of the modern design process. However, little has really been done to help ensure the accuracy of such communications. Ambiguity, mis understanding (and the resulting frustration) all create overly complex systems, nonperforming devices, and mismatched system components. The natural result of such inefficiencies is more cost, program delays, and weapon systems that cannot totally perform their prime mission (performance compromise). This paper attempts to characterize some of the causes for such communication breakdowns and postulates some likely approaches to improving the reliability of the requirements communication process. Additionally, the paper examines some past experiences that illustrate the problem and its impacts and suggests some specific solutions that should be considered now.

Self-learning machines applied to the testing of semiconductor memories

Abstract: The concept of self-learning testers is explored with reference to the detection of certain classes of soft failures. An appropriately organized machine acquires testing "know-how", while exercising memories with a virtually endless sequence of pseudo random test vectors. Verification and sorting of failures is straightforward, but imaginative compression of the acquired information is mandatory. The efficacy of the tester is, indeed, predicated on the notion of the "time trace" of a sequence of test vectors.

Analog atpg: a response to users'needs

Abstract: The need for increased reliability as well as better and simpler maintenance of wea pon systems and electronic systems gene rally is now being echoed at the highest levels. It is emphasized that interest in this aspect of the problem is not limited to military applications. We have been addressing this problem so as to take maximum advantage of inexpensive simple test equipment and computational facilities. An important criterion is that they be capable of effective use by the level of technicians available for the maintenance of the complex electronic sys tems currently in use and those being deve loped for future ground, ship or airborne use. We are developing a fuzzy automaton learning model based, in part, on the "fuzzy concept" to achieve such fault diag nosis. As a realistic goal, we seek to achieve at least an 80% throughput utili zing streamlined facilities.

Ate system architecture alternatives

Abstract: This paper proposes a definition of the concept of Auto matic Test Equipment (ATE) system architecture which encompasses all aspects of ATE system design governing the fundamental internal structure of ATE, and which accounts for all related system elements (e.g., hardware and software). This macro approach towards system architecture dif f erentiates the configuration and/or specific implementation of the system from archi tecturally significant alternatives. Examples of current and emerging ATE systems illustrate the definition concepts. Each system type is discussed in terms of salient operating features, limitations, and potential advantages.

Economic tradeoffs of in-circuit and functional testing

Abstract: With the advent of LSI devices, many manufac turers are experiencing a very complex board test problem and are looking at testers that will test all or most of the printed circuit board as an end product. This is often a narrow view and frequently an expensive mis take. What one does in one area of testing (e.g., device) affects what one does in another area of testing (e.g., board). There are many variables to consider when examining the overall test problem. There are device testers, PCB testers, testing services for devices and PCBs, burn-in ovens, automatic handlers, etc., etc. Furthermore, there are several different types of all of these testers. The systems approach to testing examines the total testing cost from receiving inspection through field service. This approach will minimize the overall testing costs and maxi mize the reliability of the end product.

Interactive fault isolation of analog hybrid circuit cards

Abstract: Modern custom hybrids which contain many analog and also digital circuits in a single flatpack, have increased the functional density of circuit cards 4 to 6 times. The consolidation of many complex functions and differing technologies on a single card has exposed the need for new fault isolation techniques, particularly for the manufacturing environment, due to high first-time through failure rates, the difficulty and cost of manual fault isolation, and the large cost of hybrid replacement. The interactive fault isolation technique optimizes the key attributes of the ATE and the human: the ATE rapidly and accurately characterizes the analog fault signatures, but the actual diagnosis is performed off-line with the aid of a fault dictionary by a human. Fault signatures of unknown signals are rapidly acquired at connector pins and at component nodes with an adaptively programmed DMM, counter, and Waveform analyzer which are appro priately connected over the ATE's instrument bus. The acquired signal characteristics are tested for validity prior to display and printing. The interactive technique does not require the development of individual diagnostic programs for each circuit card and is applicable to existing 2nd and 3rd generation ATE.

Multiple matrix switch: a high-performance universal switching system

Abstract: The requirements and design considerations involved in the development of a "Smart" switching interface are described. The implementation of the Universal Pin concept is presented, along with a discussion of switch ing system performance and reliability. The relocation of certain functions such as syntax checks, pin validity checks, and path allocation and conflict checks, from their traditional location in the compiling system to self contained firmware contributes significantly to the flex ibility of the switching interface. The resulting simpli city with which the switching interface can be incor porated into various ATE system configurations is discussed.

Design of system simulations for effective evaluation of analog test techniques

Abstract: It is much more effective to evaluate the principles of new test techniques and equipment using standard simulation models designed to reflect measurement noise, permissible parameter variation, non-linear phenomena, and drift, than to attempt demonstrations on randomly available hardware systems. The derivation and exploitation of one such stochastic simulation model of transfer functions representing the field perfornrance of a family of "healthy" electro-hydraulic servo systems is described in the paper. Generalisation of results and current categorisation studies are also outlined.

Discrete fourier transform analysis for harmonic distortion and am/fm modulation in ate testing

Abstract: The use of FFT versus DFT for signal analysis are compared in an automatic test system. For distortion and mod ulation analyses, where only a small number of spectral lines need to be computed, the DPT method is shown to be superior in flexibility and accuracy. It is shown that coherent sampling can be achioved in DFT distortion analysis by simple crossover detection without the use of windowing techniques. In AM/FM modulation analysis, the DFT program is used to recover all modula tion parameters from samples of the modulated signal without a demodulator. Frequency shift in DFT analysis to reduce leakage error from non-coherent sampling are also discussed.

Remus pre-production series

Abstract: REMUS (Rechnergesteuertes Einheitliches Mep und Priifsystern) is an Automatic Test System prograrn, conceived by the government of the Federal Republic of Germany in the mid '60's, whose objectives are to provide the FRG armed forces a standardized hardware/software auto matic test capability for electronic equipments at maintenance echelon 3. The REMUS program has progressed through a study phase and a prototype phase. The initial production phase deliveries are nearly complete; adaptation to several weapon systems is underway; and FRG Army troop trials are progressing. The REMUS system will be first fielded for support of the FRG's Gepard anti-aircraft tank electronic system in 1981. This paper provides an overview of the REMUS program; discusses significant technical changes from the prototype system; and reviews current program status and future plans.

The automatic test station as a quality assurance tool

Abstract: The quality assurance software package described in the paper was initially developed off-line from system data obtained from tape controlled production plant ATE. Results obtained to date are considered sufficiently satisfactory, general in application, and parsimonious in computational requirements for the appropriate quality assurance authorities to recommend the on-line implementation of the package to current projects utilising computer controlled ATE.

Education and training: planning ahead in ate

Abstract: The requirement to PLAN FOR TRAINING exists regardless of the means by which a newly developed or upgraded system is designed, documented, produced, installed or used. This presentation will discuss current research findings in the various areas of ATE education and training, identify specific training problems and provide explanation for planning early and efficiently. Emphasis will be placed on multiservice application of training plan processes.

An approach to ate/uut functional matching

Abstract: A comprehensive survey was recently conducted of Automatic Test Equipment (ATE) resident at 31 Naval facilities in the continental U.S. The data collected at these facilities emphasized the stimulus and response parametric characteristics of the ATE. A second survey identified commercial ATE currently available in the market place. As in the Navy survey, the data collected emphasized the stimulus and response characteristics of the ATE. Following the surveys, all ATE data were organized into functional categories which defined the envelope of test capabilities of over 25 general purpose ATEs. In a related effort, the test requirements of over 1000 Digital/Analog/RF units under test (UUTs) spanning over 20 existing Naval systems/equipments, were functionally analyzed and arranged into a normalized format using techniques and procedures derived from the Test Require ments Document (TRD). In conjunction with this effort, a computerized matching algorithm was developed, de bugged, validated, and used to compare the ATE capabilities to the UUT requirements. Using the algorithm, the test requirements of each UUT were evaluated against the capabilities of each ATE and the resulting compatibilities (or incompatibilities) identified. This paper describes these efforts in detail and presents a discussion of the results including histograms of UUT compatibility by ATE, UUT stimulus and response frequency spectrum requirements, and UUT circuit function and operating technology histograms. In general, the paper is concerned with answering the question "How can we best determine which ATE to use in testing a particular UUTTI

Avionics design for testability an aircraft contractor's viewpoint

Abstract: Designing avionics for testability is the inclusion of design provisions in the avionics to enable test of the performance capability of the avionics, to isolate avionic malfunctions to replaceable elements, and to permit adjustment and alignment of the avionics as may be required. The effective implementation of testability provisions in the design of the Air Vehicle Equipment (AVE) and the Ground Support Equipment (GSE) that comprise the avionics can improve equipment reliability and availibility while reducing equipment weight and cost. Accordingly, the operational readiness of the weapon system can be improved by effectively designing the avionics for testability. The aircraft contractor's viewpoint of designing avionics for testability is presented along with the methods and techniques employed by the aircraft contractor to effectively include testability provisions in the avionics.

A resource allocation analyzer for source programs written in atlas

Abstract: This paper describes the design of a compu ter program which will read a source program written in abbreviated test language for all systems (ATLAS) and furnish a list of resources required by the ATLAS program to successfully conduct a test. These resources include specification requirements of test equipment used to generate or to sense test signals and impedance load requirements needed for the unit under test. This design uses high level data flow analysis of ATLAS (IEEE STD 416-1976) source code to determine the required resources of an ATLAS program.

Automatic test equipment software testing

Abstract: This paper defines the functions and activi ties involved in testing Automatic Test Equipment (ATE) software. Software testing is defined here in as black box testing. In addition, an examina tion is made of four areas of test facility design tradeoffs: *simulated versus real software, both software under test and environment simulation soft ware, .organization of the components of executable test software; *selection of the methods of exiting the code under-test during execution; and *selection of the methods of assembling and loading all executable software

An approach to cost effective ate system software

Abstract: ATE suppliers and vendors will signi ficantly reduce the life cycle cost of system and UUT software by selecting languages and programming techniques which are applicable across a wide ATE product line. This paper will discuss the elements of a cost effective, total ATE software system which is being implemented for a board ATE product line.

Testability, the key to economical and operationally effective avionic test software

Abstract: The economical development of high quality avionic test soft ware is inseparably linked to the test capability of the Automatic Test Equipment (ATE), the methodology employed in the generation of the test programs and the "testability" of the Unit-Under-Test (UUT). This paper explores the interrelation ship of these three elements and the contributions each has made toward the reduction of Test Program Set (TPS) develop ment costs and to the improvements in the operational effective ness of the test programs. Further reductions in the costs of TPS development, as well as improved TPS design quality, can be realized with the institution of UUT "testability" specifications, design guidelines, and the development of a testability "Figure of Merit" for application during avionic UUT design reviews.

Ate computer! programmer or processor?

Abstract: Automatic Test Equipment (ATE) concepts and implementation techniques predate mini-computer technology by many years. This has resulted in: ATE test methodologies that do not fully utilize computer data processing capabilities. To rea lize the full potential of computer controlled ATE, we must replace the traditional "Programmer Evaluator" concepts with innovative data pro cessing techniques. Future UUT's are expected to be characterized by their high information con tent and ability to acquire and communicate this information at increasing high rates. This situation provides an excellent opportunity for ATE computer mechanizations to move into their more natural role of data processor; providing functions such as multiple sampling of groups of parameters, data filtering, wild point rejection, and the use of statistical failure criteria. If we are willing to use the available data pro cessing tools, it will allow computer controlled ATE to emerge from its "development phase" and provide significant advances in the field of automatic test.

Establishing testability standards

Abstract: One of the causitive factors relating to the lack of manifest testability en countered in Units Under Test (UUT) which are being inducted into the Department of Defense (DOD) inventory is the lack of definitive requirements and controls imposed by the customer on the vendor. The purpose of this paper will be to clarify some of the key testability issues from the perspective of a DOD customer, in general, and the Naval Air Systems Command, in particular. The paper will then proceed to recommend the manner in which these testability issues and needs can be more effectively described and controlled by the customer in order to help vendor organizations understand and provide for the test ability needs required for effective support of modern UUTs.

Ate and aircraft mechanical diagnostics

Abstract: The Army is committed to fielding a family of automatic test support systems (ATSS) to support all Army materiel. The current plan is to field the AN/USM-410 "third generation" ATE. The Army has also sponsored a significant amount of work aimed at achieving an "on condition" maintenance philosophy for major aircraft sub systems by monitoring turbine engine performance, engine mechanical condition, health of various rotating dynamic components, hydraulic systems, and structural integrity of the aircraft. The objective is to investigate the viability of accomplishing the aircraft condition monitoring and diagnostic task using ATE. Significant points are the following: non-intrusive monitoring of aircraft mechanical systems is possible; impressive benefits can be attributed to this approach, but several attempts at fielding such a system have been terminated because of excessive initial in vestment costs; and mechanical diagnostics is not a simple extension of a measurement capability.

Design-to-cost: the road to testability

Abstract: Operation and Support (O&S) costs account for an ever increasing share of weapon systems budgets. Maintenance costs are a major driver in the 0 & S cost equation. As a result, testability, as a subset of maintainability, has become of increasing concern not only to the test community, but to the weapon system designer as well. While acceptance of the notion of testability poses no serious difficulty, the methodology of its delineation and measurement requires both definition and a means of implementation. While any number of parameters can serve to characterize elements of testability, any of these is utlimately translatable to cost. It is therefore suggested that the concept of testability be addressed within a Life Cycle Cost (LCC) structure, and reduced to practice by the application of Design To Cost (DTC) tech niques.

F-16 Avionics maintenance concept and multinational aspects

Abstract: The background of the F-16 program is presented, highlighted with a discussion of the multinational aspects of the procurement. After a general pre sentation of the aircraft itself, the reader is introduced to the three level avionics maintenance concept, and the iterative process by which it was tailored to the F-16 Weapons System. The depth of maintenance performed at each level is explained, along with the type of approach used.

Software verification for large-scale ate systems

Abstract: The current trend toward greater dependence on software control in ATE systems is directing the attention of procuring agencies toward assur ing software operability prior to system installa tion. The adequacy of the ATE system software components can be assured through the implementa tion of a formal software verification program. Such a program can result in long-term benefits, including lower life cycle acquisition costs, im proved specification definition, objective product acceptance and contractual completion criteria and a motivation for focusing on the overall design adequacy of the ATE system. This paper discusses an ATE software verification methodology which is applicable to large-scale ATE systems. Discus sions include software verification methods, test objectives, test criteria, testability of require ments, tools and techniques, and documentation and controls.

Ate software, whence - whither

Abstract: Standardization efforts within ATE software have been aimed pri marily at the languages used to prepare test programs. In the future the diversity of computer con figurations available to ATE will increase tremendously. To take full advantage of this diversity in a coherent manner will require some standardization of operating system features. The primary goal of such standardization should be the operator to computer interface. Given such standardization a wide range of possibilities become available without the disadvantages that diverse operator interfaces impose.