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This work presents an investigation of methods of verifying computers to an Instruction Set Architecture and recommends a method suitable for Air Force use to verify vendor produced implementations of MIL-STD-1750. This study's purposes and goals follow: Investigate methods of verifying computers to an Instruction Set Architecture and recommend a method suitable to SEAFAC for certifying vendor produced implementations of MIL-STD-1750; Make cost-effective use of existing SEAFAC resources; Strive for vendor/implementation independence; Recommend a verification approach based on a cost trade-off analysis; and Provide sufficient descriptive information about the recommended approach so that the Air Force can: Plan future funding and personnel requirements; Write specifications for hardware and software necessary to support approach; and Contract for (or develop internally) the necessary facilities.

Electrical characterizations were performed on 16K dynamic RAMs available from the merchant semiconductor industry. Based on the data obtained, parameter limits were established and proposed for a draft 38510 specification. The data, proposed limits, and related discussion are presented. (Author)

The flight software executes in the Helmet-Mounted-Display Processor (HMDP) to provide vector-graphic displays that may be viewed on a helmet-mounted display (HMD), or a heads-up display (HUD). There are several different display formats, each of which is selectable via pushbutton switches mounted in a cockpit mockup. In addition, to these display selection inputs, the program is responsive to data value inputs which can be expressed using these same pushbuttons under various modes. Dynamic data received from actual aircraft electronics units are accommodated by an analog input capability and a synchro input capability. These dynamic inputs define the aircraft state and the helmet pointing angles to the flight software program. The various display generation routines that comprise the flight software program use these dynamic and static inputs to derive meaningful flight displays in several specific orientations, all of which are dynamically responsive to aircraft translation and rotation, as well as head pointing angle. In addition, the vector-graphics displays when viewed on the HMD may be mixed with a T.V. image.

The Head Switching Software Package is a system of programs which provide the capability to study item selection and switch activation by an operator's head line of sight. Data is gathered on the speed and accuracy of accomplishing discrete pointing tasks with the helmet mounted sight and stored on magnetic tape for subsequent data analysis. The programs were written for an IBM System/370, Model 155 computer running under the standard MFT version of the Operating System. Assembler language was used in coding the executive program and Fortran was used for the subroutine programs. The IBM System/370 Operating System Graphic Subroutine Package (GSP) for Fortran IV was utilized for the graphic software support. (Author)

The objective of this effort is to reduce avionic system life cycle cost by developing a set of standard power supply modules for application in Air Force avionics. The results of this effort to develop such a set of power supply modules are discussed. Included in this report are: an examination of avionic power requirements to determine the extent of commonality in terms of output voltage and power level; an analysis and evaluation of alternative power supply designs and selection of the optimum approach to meet the defined requirements; and extension of these studies to include more equipment items of recent design and definition of other module types that offer cost advantages to the module set proposed; and a prototype design, development and construction of a representative sample of the recommended module set and a life cycle cost comparison of the standard vs. custom approach.

The ALQ-T4 EWO Crew Station Simulation Programs were written for the Crew Station Integration Branch (HED), Human Engineering Division, Aerospace Medical Research Laboratory. The overall function of the entire system of programs is to provide the capability for studying the performance of a trained Electronic Warfare Officer (EWO) during an electronic warfare simulation, to support studies to analyze the impact of the addition of new equipment, and the organization of old equipment on crew performance. A real-time program controls and monitors an AN/ALQ-T4 B-52 EW Crew Station Simulator that has been modified to include a set of equipment changes associated with the Advanced Phase VI B-52 EW Crew Station Project. The subject response times, at which all input transitions occur, and the times that the emitters stations are turned on/off are recorded for subsequent analysis. This sytem was written for an IBM System/370, Model 155 Computer. OS Assembler Language and FORTRAN IV were used in coding the subroutines.

Circuits to add a passive ranging capability to the Interferometric Landmark Tracker (ILT) to form a Passive Range Interferometer Sensor (PRAIS) were built and tested in the laboratory. The laboratory test data were used in a Monte Carlo simulation to demonstrate the performance of the PRAIS Navigation System in a highly eliptical orbit and a synchronous (1 deg inclination) orbit. Navigation accuracies better than 1000 ft and attitude accuracy better than 10 arcsec were indicated by the analyses. (Author), See also Volume 2, AD-A038 489.

This is volume III of a three-volume final report of the Self-Contained High Altitude Navigation System (SCHANS) study. Volume I consists of a system summary, and Volume II presents the results of the seven technical tasks of the contract. This Volume III consists of the following three appendices: Appendix A, Interferometric Landmark Tracker (ILT) Receiver Electrical Design Description, Appendix B, SCHANS Pulse Conversion Unit (PCU) Final Report, Appendix C, SCHANS Operational Software Computer Program Development Specification., See also Volume 1, AD-A038 488.

This report is Volume II of the three-volume final report on the Self-Contained High Altitude Navigation System (SCHANS) study. Volume I provides a summary description of the system concept, operation, performance, and configuration as well as a statement of application potential, conclusions, and recommendations. This volume describes results of SCHANS contract work by task. Volume III contains circuit level electrical design description of the Interferometric Landmark Tracker (ILT) Receiver and the Pulse Conversion Unit (PCU); it also contains an operational software Computer Program Development Specification., See also Volume 3, AD-A038 490.

The Digital Switching Experiment Program is an interactive control system used for evaluating three different switching concepts in a simulated aircraft environment. The basic goal of the experiment is to assess pilot switching performance on a simple communications task while engaged in a tracking task that approximates formation flying. The three switching concepts to be evaluated include: (1) a conventional UHF control head (ARC-34) to provide baseline data on present-day manual systems, (2) a pushbutton keyboard (F-15 navigation panel switches) that reflects the proposed DAIS concept for fighter aircraft and, (3) a voice command system that employs an automatic speech recognition system to augment the control of cockpit functions. The program was written for an IBM S/370, Model 155 Computer using the MFT version of the standard Operating System. The simulated cockpit is interfaced through an IBM 1827 Data Control Unit and the graphics displays are presented on two IBM 2250 Display Units. Both assembler language and FORTRAN IV were used in the software development. (Author)

System design, analysis and tests were performed in preparation for a joint U.S. Army/Air Force demonstration flight test. This flight test will involve use of the Air Force Advanced Location and Strikes System (ALSS) Distance Measuring Equipment (DME) navigation and guidance techniques for control of a Hawk missile on a surface-to-surface trajectory. Requirements are defined for the interface between the DME Weapon Guidance Subsystem and the Hawk flight control system. A DME data link antenna system was designed. Scale model antenna pattern test results are presented which validate the performance for the DME, Telemetry and Command Destruct antennas needed for flight tests. A projected flight test geometry is defined relating the missile trajectory and ALSS ground station locations. Functional requirements are identified for modifications necessary to the ALSS software to provide missile control during the flight tests. (Author)

The Remotely Piloted Vehicle Mission Control System (RMCS) Simulation Program is a real-time, interactive, graphics program which simulates a hypothetical mission control center. It provides a means for analyzing the effects of numerous variables on the operator performance of a five-man team whose task is to control up to 35 Remotely Piloted Vehicles (RPVs) through the enroute, terminal, and return phases of a simulated strike mission. The enroute and return phases are performed by four operators seated at IBM 2250 Display Units. The terminal phase is simulated by a single operator who controls a remotely located terrain table which is interfaced to his control station through an IBM 1827 Data Control Unit.

The DAIS Triple Task Experiment Program is a real-time, interactive, graphics system containing processing functions for simultaneously executing three separate experimental tasks. The primary task is a flight control task in which a subject 'flies' a simulated aircraft using digital and graphic display indicators to represent the aerodynamic parameters of the aircraft. A second task involves a multifunction keyboard on which the subject is instructed to perform specific switching selections related to the communications and IFF systems onboard the simulated aircraft. And the third task is an information processing task designed to assess cognitive reserve capacity under various primary task loading conditions. The program was written for an IBM System/370, Model 155 computer operating under the standard MFT version of the Operating System. Both assembler language and Fortran were used in coding the subroutines and the IBM 2250 Graphics Programming Services were utilized for the graphic software support. (Author)

The Bi-Modal Short-Term Recognition Memory (BMSTRM) program provides a capability for measuring human reaction time and error rate for probe stimuli which are to be recognized in relation to a memory set that is presented prior to each trial. The experiment is conducted using either visual stimuli presented on an IBM 2250 Display Unit, or stimuli generated by laboratory equipment, or both. The visual stimuli can be any set of visual symbols that can be constructed from line segments. The user may specify the starting and ending coordinates for up to 12 line segments when defining each of 40 symbols. In addition, the program can control 10 electrical relay closures in equipment external to the data processing set. This allows control of unique stimuli such as auditory tone stimuli. The program, via parametric input, can control the stimulus duration, the inter-stimulus time interval, the inter-trial time interval, and the time delay between start switch initiation and presentation of the first stimulus. The program was written for an IBM System/370, Model 155 computer and employs the IBM 2250-3 Display Unit for visual symbol presentation and the IBM 1827 Data Control Unit for control of stimuli presentation by external laboratory equipment. (Author)

The Analog Digitization Program is a real-time program which provides the capability for continuous sampling of one to sixteen analog input channels. The resultant digital representations of the analog samples are then stored on a disk pack for subsequent analysis. The program was written for an IBM System/370, Model 155 computer operating under the standard MFT version of the Operating System. Assembler language was used in coding the program. The IBM 2250 Graphics Programming Services were utilized for the graphic software support. (Author)

The Voltscan Program provides the capability to graphically display four channels of digitized analog samples. The program was written for an IBM System/370, Model 155 computer operating under the standard MFT version of the Operating System. Assembler language and Fortran were used in coding the program. The IBM 2250 Graphics Programming Services were utilized for the graphic software support. (Author)

A laboratory evaluation of an Interferometric Landmark Tracker (ILT) for an autonomous spacecraft navigation system was conducted. The system processes ILT, inertial reference unit, and star sensor data in a Kalman filter to provide in-space navigation. Sighting accuracy measurements were made over a 120 degree field-of-view on a four-antenna interferometer in an anechoic chamber. Error data from the interferometer measurements were used as inputs to Monte Carlo simulations of the spacecraft and orbital dynamics to determine navigation accuracy for several orbital conditions. Navigation errors and interferometer sighting errors were analyzed in terms of order statistics and cumulative distributions.

The studies conducted under this phase O HANS Study contract evaluated the performance of a Passive Ranging Interferometer Sensor (PRAIS) when used for autonomous navigation of high altitude spacecraft. The autonomous navigation system investigated consisted of the PRAIS, a digital computer and an Attitude Determination System (ADS). Performance of this HANS is five orbits encompassing a range of orbital altitudes from 400 to 150,000 nm was evaluated using covariance analysis for the trade studies and parametric sensitivity analyses. HANS performance in a synchronous equatorial orbit and highly eccentric (Molniya) orbit was demonstrated via a Monte Carlo simulation using order statistics., See also Volume 5 dated Mar 75, AD-A008 486.

Analysis and simulation of a Passive Ranging Interferometer Sensor (PRAIS) used to provide autonomous navigation of spacecraft at average altitudes greater than 5000 nm was conducted. Navigation accuracy of a High Altitude Navigation System (HANS), configured with the PRAIS in conjunction with a digital computer and an Altitude determination system (ADS), was evaluated for five orbits spanning the altitude range of 400 to 150,000 nm. Performance of this HANS configuration was demonstrated with Monte Carlo simulation using order statistics., See also Volume 2 dated Mar 75, AD-A008 483.

This report describes the system configuration trade studies analyses, defines critical system parameters, documents the results and selects a high altitude navigation system concept. During this Task 1 effort two basic system configurations were analyzed and their sensitivity to landmark parameters and tracking schedule established. The first of these configurations is based on the Interferometric Landmark Tracker (ILT) studied and tested under the Autonomous Navigation Technology ANT Contracts; the second configuration adds a passive ranging capability to the ILT. These systems are described in Section 2.0. The results obtained using a covariance analysis program are presented in Section 3.0 and indicate the feasibility of the Passive Ranging Interferometer Sensor (PRAIS) concept. Critical parameters are identified in Section 4.0. Section 5.0 describes the system selection., See also Volume 1 dated Mar 75, AD-A008 482, and Volume 3 dated Mar 75, AD-A008 484.

This report, Volume 5 of the High Altitude Navigation System (HANS) Study, presents the sensitivity analyses carried out on the selected HANS system. Two Passive Range Interferometer Sensor (PRAIS) sensitivity analyses were conducted, one assuming atomic clock control of radar PRI, and one assuming crystal clock stability typical of MTI radars. Sensitivity data for the five study orbits is presented in terms of percent change in position error from the position error under nominal system (error) conditions. In these analyses two landmarks were tracked simultaneously, one with both passive ranging and interferometer landmark tracker (ILT) - the other with only the ILT., See also Volume 4 dated Mar 75, AD-A008 485, and Volume 6 dated Mar 75, AD-A008 487.

This document is Volume 4 of the High Altitude Navigation System (HANS) study - System Preliminary Design Description. This volume describes the system studied by IBM to provide autonomous navigation for high altitude spacecraft. This spacecraft system concept consists of a Passive Range Interferometer Sensor (PRAIS) which provides precise angle tracking of and ranging to known radar landmarks, a digital computer to process the sensor data in a 19 state Kalman filter, and an attitude determination system., See also Volume 3 dated Mar 75, AD-A008 484, and Volume 5 dated Mar 25, AD-a008 486.

This specification establishes the requirements for performance, design, test, and qualification of one mission-design-series of equipment identified as the Passive Ranging Interferometer Sensor (PARIS). This CEI is used to provide the terrestial reference essential to the High Altitude Navigation system (HANS) for precise spacecraft navigation. This CEI requires RF radiation from ground radars of known location operating in the E/F frequency band., See also Volume 2 dated Mar 75, AD-A008 483, and Volume 4 dated Mar 75, AD-A008 485.

The primary objectives of the investigation were to perform the following four tasks: (1) Define the functional transfer functions for the following device and channels - IBM model 2314 disc drive controller; IBM system 360/370 channels; and, NTDS parallel and serial channels as analyzed by IBM ASC. This also included the IOA and IOA-E: (2) Prepare MCU micro-code, written in AMIL, to emulate the functional transfer functions defined under Task 1; (3) Define modeling statistics to assay performance of the MCU in emulating each of the transfer functions; (4) Perform emulation of the functional transfer functions to determine the performance and feasibility of attaching to the MCU.

The solution to the standard steady state LQG problem is a controller whose order equals the order of the plant model. For many high order plant models, a reduced order controller which is easier to mechanize can be used with good performance. A methodology is described for solving the discrete-time, steady state LQG problem with the constraints that the controller be of reduced order and that linear combinations of the controller states estimate particular plant model state variables. Formulas for simplifying the gradient calculations are introduced. (Author), This article is from 'Transactions of the Army Conference on Applied Mathematics and Computing (1st) Held at Washington, DC on 9-11 May 1983,' AD-A139 224, p443-454.

A detailed design of the receiver portion of a flight test model Interferometric Landmark Tracker (ILT) was completed. Prototype RF subassemblies and breadboard circuits were built and tested. Test results indicate the flight test model ILT receiver will provide an accuracy of 0.57 phase one sigma over the frequency range of 2.5 to 2.9 GHz, the specified temperature range of 30 F to +160 F and the received signal dynamic range of 50 dB. (Author)

The report details a study of the resolution of a dielectric membrane display device. The areas of study included the analysis and selection of a deformable dielectric membrane, incorporation of this membrane into a sealed cathode ray tube, selection and modification of the writing electron gun, and subsequent testing of the complete display device to determine its resolution characteristics. The study results show that the resolution of the device could be increased from 280 to 440 lines per inch, by proper selection of the writing electron gun and the dielectric membrane. (Author)

The report presents a study of a dielectric membrane used as a light valve in a CRT. The areas of study included the schlieren optical system, the characteristics of the dielectric membrane; resolution, write and erase speed, and the storage capability of the composite membrane. It was shown that a thin dielectric substrate for electronic charge control and a corresponding elastomer (deformable) layer on the substrate with a suitable reference plane, provided many desirable features. The dielectric membranes were fabricated and tested successfully in demountable CRT. The resulting performance data was found to correlate with the analytical studies. (Author)

Results are reported on the failure mechanisms of multilayer interconnection boards (MIBs) subjected to long-term temperature-cycling tests. The underlying failure process, consisting of low-cycle copper fatigue and leading to circuit open due to fracture, was found to occur at different rates and in different locations as a function of: (1) MIB design geometry and material parameters; (2) manufacturing process parameters; and (3) temperature cycling test profile values. Of particular interest is the presentation of comparative test results showing that straight-wall PTH (plated-through-hole) construction provides somewhat greater resistance to thermal fatigue than does etched-back PTH construction. Results are also given for comparative tests on early-vintage MIBs fabricated using polyimide materials and fluroborate-copper PTH plating. (Author)

The paper reviews some of the more significant developments in materials and processes used in the fabrication of flexible printed interconnection cables. Polyimide printed circuit cables are emphasized, and a typical manufacturing process sequence for cables of this type is outlined and discussed. (Author)

The object of the research is the design and fabrication of a versatile experimental display module incorporating an array of 60 gallium-phosphide diodes as light-emitting elements. This effort includes the associated control circuitry for accessing, latching, and providing the necessary input waveforms and impulses for X-grid and Y-grid access. This report covers the work accomplished towards the development of an experimental display module using red-light-emitting gallium-phosphide diodes. Both analog and digital X - Y scanning circuits were breadboard tested. Techniques for measuring the light output and for selecting diodes for high-density arrays were also developed. (Author)

The report describes a process for vacuum-forming thin sheets of plastic material into control and display panel mockups. The description includes techniques for fabricating controls and annunciators plus requirements for drawings, tools, equipment, and materials. The vacuum-forming process, which is well established in the plastics industry for fabricating parts in large quantities, is fast and inexpensive. In this report, the fabrication of a typical mock-up panel is used to illustrate the vacuum-forming process. (Author)

This report describes tests that will be performed to determine the properties of radiation-induced currents in various types of capacitors. The tests will be conducted at a linear accelerator from 13 to 17 December 1965. The report also describes tests on magnetic core memories that will be conducted at the linear accelerator during the same period. These tests are to be performed to confirm that changes in magnetic-core voltages during previous tests were not caused by irradiation. The voltage changes are believed to have been caused by the magnetic field of a vacuum pump. (Author)

The report describes the investigation of the dielectric isolation of an integrated circuit while under electron irradiation by studying the two primary effects of induced transient conductivity and charge storage in silicon dioxide layers. A mathematical approximation describing physical processes, outlined in a qualitative physical model, was developed which consists of a set of partial differential equations. A combined set of differential and difference equations have been constructed and solutions for these equations were found by using SCEPTRE's differential equation solution capability. This computer program calculates transient conductivity, field distributions and the charges in the dielectric before and after irradiation. The average internal electric field in the silicon dioxide layer of SOS-structures was measured by means of optical probing with a Helium-Neon laser utilizing the electro-optical Kerr effect. For an unirradiated structure the average field in the oxide at zero bias was determined as 4 x 40,000 V/cm. In an identical SOS-structure electron bombarded with a total dose of 5.5 x 4,000 rads an average field of 1.2 x 120,000 V/cm was measured corresponding to 2.6 x 10 to the 12th power charges per sq cm in the dielectric. It could be concluded that the field in the dielectric at zero bias is directed toward the polysilicon layer. Positive charges stored in the dielectric are located in the vicinity of the interface silicon dioxide single crystal silicon. (Author)

The results of a test program to investigate failure mechanisms of Multilayer Interconnection Boards (MIB's) are reported. The overall objective was a more fundamental understanding of the reliability characteristics of MIB's, as related to design, manufacturing and environmental variables. The test approach used was an experimental type of accelerated testing, called 'enhanced-defects' testing. Implementation was successfully carried out using two special MIB Test Vehicles designed to exhibit controlled-enhancement of failure occurrence during environmental tests. Test samples were prepared by marginal off-setting of selected design and processing variables. Test results for MIB open failure modes revealed a PTH-fracture failure mechanism which occurs as a result of temperature change, and is relatable to MIB material properties, PTH geometry and processing variables. MIB short failure modes were shown to be largely dependent on temperature and relative humidity but also relatable to MIB design variables, e.g., line spacing and processing variables. Failure models for MIB failure mechanisms are postulated. (Author)

The purposes of the Synergistic Navigation System Study are: To determine the portion of theoretically available improvements which can be realized when practical implementation is considered; to assess the cost of the gains in terms of computer execution time and storage requirements; and to recommend an optimal filter design for flight test verification. Having concluded in the Phase I effort that major navigation accuracy improvements were possible through optimal data processing techniques, it was necessary in the Phase II effort to explore many areas of uncertainty. These areas include the sensitivity of the concept to unknown error magnitudes and distributions, to maneuvering flight paths, to approximations required in implementing the concept, and to implications upon data processing equipment. The major conclusion is that a significant improvement over conventional filter design is maintained under broad variation in a priori statistic. Several additional conclusions are drawn regarding system performance versus frequency of position fixes, the dependence of system performance on flight path and the relative effects on open and closed loop compensation by the filter cycle update time. A final conclusion was that closed loop compensation is preferred, and that a filter cycle update time of 30 seconds is satisfactory. (Author)