37,514 research outputs found

    An assembler for the MOS Technology 6502 microprocessor as implemented in jolt (TM) and KIM-1 (TM)

    Get PDF
    Design of low-cost, microcomputer-based navigation receivers, and the assembler are described. The development of computer software for microprocessors is materially aided by the assembler program using mnemonic variable names. The flexibility of the environment provided by the IBM's Virtual Machine Facility and the Conversational Monitor System, make possible the convenient assembler access. The implementation of the assembler for the microprocessor chip serves a part of the present need and forms a model for support of other microprocessors

    Concurrent simulation of a parallel jaw end effector

    Get PDF
    A system of programs developed to aid in the design and development of the command/response protocol between a parallel jaw end effector and the strategic planner program controlling it are presented. The system executes concurrently with the LISP controlling program to generate a graphical image of the end effector that moves in approximately real time in response to commands sent from the controlling program. Concurrent execution of the simulation program is useful for revealing flaws in the communication command structure arising from the asynchronous nature of the message traffic between the end effector and the strategic planner. Software simulation helps to minimize the number of hardware changes necessary to the microprocessor driving the end effector because of changes in the communication protocol. The simulation of other actuator devices can be easily incorporated into the system of programs by using the underlying support that was developed for the concurrent execution of the simulation process and the communication between it and the controlling program

    Development of a prototype automatic controller for liquid cooling garment inlet temperature

    Get PDF
    The development of a computer control of a liquid cooled garment (LCG) inlet temperature is descirbed. An adaptive model of the LCG is used to predict the heat-removal rates for various inlet temperatures. An experimental system that contains a microcomputer was constructed. The LCG inlet and outlet temperatures and the heat exchanger outlet temperature form the inputs to the computer. The adaptive model prediction method of control is successful during tests where the inlet temperature is automatically chosen by the computer. It is concluded that the program can be implemented in a microprocessor of a size that is practical for a life support back-pack

    An integrated and modular digital modeling approach for the space station electrical power system development

    Get PDF
    An electrical power system for the Space Station was designed, developed and built. This system provides for electrical power generation, conditioning, storage, and distribution. The initial configuration uses photovoltaic power generation. The power system control is based on a hierarchical architecture to support the requirements of automation. In the preliminary design and technology development phase of the program, various modeling techniques and software tools were evaluated for the purpose of meeting the Space Station power system modeling requirements. Rocketdyne and LeRC jointly selected the EASY5 simulation software, developed by Boeing Computer Services, as a system level modeling tool. The application of the selected analytical modeling approach to represent the entire power system is described. Typical results of model predictions are also summarized. The equipment modeled includes solar arrays, dc to ac converters, resonant inverters, battery storage system, alternator, transmission line, switch gear, and system level microprocessor controls. During the advanced development phase of this program, several models were developed using this approach

    Advanced CO2 removal process control and monitor instrumentation development

    Get PDF
    A progam to evaluate, design and demonstrate major advances in control and monitor instrumentation was undertaken. A carbon dioxide removal process, one whose maturity level makes it a prime candidate for early flight demonstration was investigated. The instrumentation design incorporates features which are compatible with anticipated flight requirements. Current electronics technology and projected advances are included. In addition, the program established commonality of components for all advanced life support subsystems. It was concluded from the studies and design activities conducted under this program that the next generation of instrumentation will be greatly smaller than the prior one. Not only physical size but weight, power and heat rejection requirements were reduced in the range of 80 to 85% from the former level of research and development instrumentation. Using a microprocessor based computer, a standard computer bus structure and nonvolatile memory, improved fabrication techniques and aerospace packaging this instrumentation will greatly enhance overall reliability and total system availability

    Fault Injection for Embedded Microprocessor-based Systems

    Get PDF
    Microprocessor-based embedded systems are increasingly used to control safety-critical systems (e.g., air and railway traffic control, nuclear plant control, aircraft and car control). In this case, fault tolerance mechanisms are introduced at the hardware and software level. Debugging and verifying the correct design and implementation of these mechanisms ask for effective environments, and Fault Injection represents a viable solution for their implementation. In this paper we present a Fault Injection environment, named FlexFI, suitable to assess the correctness of the design and implementation of the hardware and software mechanisms existing in embedded microprocessor-based systems, and to compute the fault coverage they provide. The paper describes and analyzes different solutions for implementing the most critical modules, which differ in terms of cost, speed, and intrusiveness in the original system behavio

    A smart end-effector for assembly of space truss structures

    Get PDF
    A unique facility, the Automated Structures Research Laboratory, is being used to investigate robotic assembly of truss structures. A special-purpose end-effector is used to assemble structural elements into an eight meter diameter structure. To expand the capabilities of the facility to include construction of structures with curved surfaces from straight structural elements of different lengths, a new end-effector has been designed and fabricated. This end-effector contains an integrated microprocessor to monitor actuator operations through sensor feedback. This paper provides an overview of the automated assembly tasks required by this end-effector and a description of the new end-effector's hardware and control software

    A project to transfer technology from NASA centers in support of industrial innovation in the midwest

    Get PDF
    A technology transfer program utilizing graduate students in mechanical engineering at the University of Kansas was initiated in early 1981. The objective of the program was to encourage industrial innovation in the Midwest through improved industry/university cooperation and the utilization of NASA technology. A related and important aspect of the program was the improvement of graduate engineering education through the involvement of students in the identification and accomplishment of technological objectives in cooperation with scientists at NASA centers and engineers in industry. The pilot NASA/University Industrial Innovation Program was an outstanding success based on its ability to: attract top graduate students; secure industry support; and stimulate industry/university cooperation leading to enhanced university capability and utilization of advanced technology by industry
    corecore