Showing papers on "System integration published in 1982"

Hardware-in-the-loop simulation for an active missile:

Abstract: A hardware-in-the-loop simulation has been developed to eval uate the performance of active missiles from prelaunch to inter cept. The facility is used for system integration, design verifica tion,...

Advanced Batteries For Load-Leveling The Utility Perspective on System Integration

Abstract: Developments associated with advanced batteries for large scale power applications have resulted in renewed interest in the use of batteries as a form of electric energy storage by utilities. Concerns which must be addressed to facilitate commercialization of battery systems and their integration into electric power systems are discussed along with programs and demonstrations designed to address these concerns and support the development of battery systems.

Combining analysis with optimization at Langley Research Center - An evolutionary process

Abstract: The evolutionary process of combining analysis and optimization codes was traced with a view toward providing insight into the long term goal of developing the methodology for an integrated, multidisciplinary software system for the concurrent analysis and optimization of aerospace structures. It was traced along the lines of strength sizing, concurrent strength and flutter sizing, and general optimization to define a near-term goal for combining analysis and optimization codes. Development of a modular software system combining general-purpose, state-of-the-art, production-level analysis computer programs for structures, aerodynamics, and aeroelasticity with a state-of-the-art optimization program is required. Incorporation of a modular and flexible structural optimization software system into a state-of-the-art finite element analysis computer program will facilitate this effort. This effort results in the software system used that is controlled with a special-purpose language, communicates with a data management system, and is easily modified for adding new programs and capabilities. A 337 degree-of-freedom finite element model is used in verifying the accuracy of this system.

Asynchronous Interactive Control Systems

Abstract: A class of interactive control systems is derived by generalizing interactive manipulator control systems. The general structural properties of such systems are discussed and an appropriate general software implementation is proposed. This is based on the fact that tasks of interactive control systems can be represented as a network of a finite set of actions which have specific operational characteristics and specific resource requirements, and which are of limited duration. This has enabled the decomposition of the overall control algorithm into a set of subalgorithms, called subcontrollers, which can operate simultaneously and asynchronously. Coordinate transformations of sensor feedback data and actuator set-points have enabled the further simplification of the subcontrollers and have reduced their conflicting resource requirements. The modules of the decomposed control system are implemented as parallel processes with disjoint memory space communicating only by I/O. The synchronization mechanisms for dynamic resource allocation among subcontrollers and other synchronization mechanisms are also discussed in this paper. Such a software organization is suitable for the general form of multiprocessing using computer networks with distributed storage.

Spacelab: Subsystems Performance Capabilities

Abstract: Spacelab, with its multiplicity of configuration options and associated subsystem capabilities provides the user with a unique set of environments and facilities to conduct scientific investigations in space. This paper provides an insight into the Spacelab resources and their efficient application to payloads and experiment integration for the manned and unmanned options. Subsystem capabilities and constraints for various types of missions and experiments are discussed in terms of structural support, power, thermal conditioning, pointing and stability, and command and data management.

Human factors in operations design

Abstract: The manner in which organizations develop their organizational structure is considered, taking into account an example in which the environment changes for an older organization. In such cases, it would be preferable to have some theoretical foundation on which to base the restructuring of the organization to meet new environmental needs. A description is given of a theoretic foundation based on the principles of Differentiation/Integration and Procedural/Knowledge based operations. The organizational design principle of Differentiation and Integration has been presented by Lawrence and Lorsch (1969). The differentiation/integration processes are related to the organizational structures presented in studies concerning NASA Deep Space Network (DSN) operations. The principles presented provide valuable tools for analyzing operations organization.

The software engineering of a microcomputer application system

Abstract: A system development methodology is outlined before describing its application to the development of a microcomputer system. Structured analysis techniques were used for determining the information flow through the system. The system was then structured into modules using structured design and information hiding techniques. The detailed design of the system was described in pseudocode. The system was coded in assembler supplemented by a set of structured programming macros. A systematic bottom-up testing procedure was adopted for system integration.

Integrated flight and fire control: systbm integration and testing and the role of onboard simulation

Abstract: This paper describes the methodology used for system integration and testing far the Integrated Flight and Fire Control System. This system provides a coupling between the flight control system and fire control system to steer out tracking errors based on information derived from an onboard sensorltracker. Three primary test facilities were used: the Software Test Facility, the Manned Air Combat Simulator, and the aircraft itself equipped with the Onboard Simulation capability. The Onboard Simulation feature provided a unique capability to perform closed loop system checkout on the a i r craft both on the ground and in airworthiness test flights.

Demonstration Advanced Avionics System (DAAS) function description

Abstract: The Demonstration Advanced Avionics System, DAAS, is an integrated avionics system utilizing microprocessor technologies, data busing, and shared displays for demonstrating the potential of these technologies in improving the safety and utility of general aviation operations in the late 1980's and beyond. Major hardware elements of the DAAS include a functionally distributed microcomputer complex, an integrated data control center, an electronic horizontal situation indicator, and a radio adaptor unit. All processing and display resources are interconnected by an IEEE-488 bus in order to enhance the overall system effectiveness, reliability, modularity and maintainability. A detail description of the DAAS architecture, the DAAS hardware, and the DAAS functions is presented. The system is designed for installation and flight test in a NASA Cessna 402-B aircraft.

Aircraft interrogation and display system: A ground support equipment for digital flight systems

Abstract: A microprocessor-based general purpose ground support equipment for electronic systems was developed. The hardware and software are designed to permit diverse applications in support of aircraft flight systems and simulation facilities. The implementation of the hardware, the structure of the software, describes the application of the system to an ongoing research aircraft project are described.

Shuttle Payload Integration: Contamination Aspects

Abstract: As part of the development of the Space Shuttle, a payload integration system has been established. This integration system or process encompasses several technical disciplines, one of which is concerned with the control of molecular and particulate contamination. Specific integration procedures and documentation have evolved that reflect the incorporation of payload/Space Transportation System contamination requirements and capabilities. Of the 38 payloads in the payload integration system currently, about 20% are considered sensitive to contamination in that special precautions must be taken to ensure that contamination from the Space Shuttle Orbiter does not impair payload function. Most of these payload requirements have been satisfied by the incorporation of controlled ground operations discipline and installation of a payload bay liner, which isolates the payload from the Orbiter systems. Some payloads, however, provide covers for sensitive payload instrumentation.

Problems related to the integration of fault tolerant aircraft electronic systems

Abstract: Problems related to the design of the hardware for an integrated aircraft electronic system are considered. Taxonomies of concurrent systems are reviewed and a new taxonomy is proposed. An informal methodology intended to identify feasible regions of the taxonomic design space is described. Specific tools are recommended for use in the methodology. Based on the methodology, a preliminary strawman integrated fault tolerant aircraft electronic system is proposed. Next, problems related to the programming and control of inegrated aircraft electronic systems are discussed. Issues of system resource management, including the scheduling and allocation of real time periodic tasks in a multiprocessor environment, are treated in detail. The role of software design in integrated fault tolerant aircraft electronic systems is discussed. Conclusions and recommendations for further work are included.

On getting our em act together and putting it on a navy ship

Abstract: Design and production of a fighting ship is more complex than even we in the shipbuilding community know. Electro-magnetic (EM) systems have become vital organs of the Navy combatant. EM communication systems provide mission guidance and coordination, EM navigational aids enable precise positioning worldwide, EM surveillance systems detect and warn of the threat, and EM tracking systems permit timely engagement. This paper addresses the major engineering disciplines competing and trading off to produce Navy ships. U.S. Navy activity in each area is discussed, with commentary on the systems engineering relationship among them, from the EM perspective. In stressing the need for whole ship systems engineering, the paper features an advanced communications system architecture and discusses its implications in ship design and performance. Assessments are made of present priorities and effectiveness and how close we are to realizing EM combat system integration.

Development of an Avionics System Integration Self-Test

Abstract: A new method for ground testing a complex avionics system in an integrated manner has been developed. A case study for the space shuttle, on which the concept has been successfully implemented, is described. The advantages over current testing techniques and the extension of the concept to other strategic systems are discussed.

Evaluation of automated decisionmaking methodologies and development of an integrated robotic system simulation, volume 2, part 1. Appendix A: Software documentation

Abstract: Documentation of the preliminary software developed as a framework for a generalized integrated robotic system simulation is presented. The program structure is composed of three major functions controlled by a program executive. The three major functions are: system definition, analysis tools, and post processing. The system definition function handles user input of system parameters and definition of the manipulator configuration. The analysis tools function handles the computational requirements of the program. The post processing function allows for more detailed study of the results of analysis tool function executions. Also documented is the manipulator joint model software to be used as the basis of the manipulator simulation which will be part of the analysis tools capability.

D4 Digital Channel Bank Family: Custom-integrated circuits for digital terminals

Abstract: This article describes the design steps for generating custom and semi-custom integrated circuits for digital terminals. The design styles and processing techniques are discussed with special emphasis on the interaction of the device organization with the system organization. Metal-oxide-semiconductor technology makes possible high-packing-density custom integration. Logic conversion is verified by simulation, layout is performed automatically, and timing is verified by using layout information as input to the timing simulator. Gate arrays facilitate semi-custom designing at low cost for modest scales of integration. The same design automation tools are used for both custom and semi-custom integration. Complementary bipolar integrated circuit technology realizes high-performance analog circuitry and can be combined with buried injector logic to integrate both analog and digital circuitry on the same chip. The combination of these technologies offers cost-effective system integration for digital terminals.