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Background; SAVVAS architecture; software portability; history of Ada; isolation of non-portable code; simple terminal interface package; constraints of language features; and virtual interfaces are outlined. This presentation is represented by viewgraphs only.
The paper presents the Flow Analysis Software Toolset (FAST) to be used for fluid-mechanics analysis. The design criteria for FAST including the minimization of the data path in the computational fluid-dynamics (CFD) process, consistent user interface, extensible software architecture, modularization, and the isolation of three-dimensional tasks from the application programmer are outlined. Each separate process communicates through the FAST Hub, while other modules such as FAST Central, NAS file input, CFD calculator, surface extractor and renderer, titler, tracer, and isolev might work together to generate the scene. An interprocess communication package making it possible for FAST to operate as a modular environment where resources could be shared among different machines as well as a single host is discussed.
Technological and planning issues for data management, processing, and communication on Space Station Freedom are discussed in reviews and reports by U.S., European, and Japanese experts. The space-information-system strategies of NASA, ESA, and NASDA are discussed; customer needs are analyzed; and particular attention is given to communication and data systems, standards and protocols, integrated system architectures, software and automation, and plans and approaches being developed on the basis of experience from past programs. Also included are the reports from workshop sessions on design to meet customer needs, the accommodation of growth and new technologies, and system interoperability.
The Naval Postgraduate School has been conducting research into the design and testing of an Autonomous Underwater Vehicle (AUV). One facet of this research is to incrementally design a software architecture and implement it in an advanced testbed, the AUV II. As part of the high level architecture, a Mission Executor is being constructed using CLIPS (C Language Integrated Production System) version 5.0. The Mission Executor is an expert system designed to oversee progress from the AUV launch point to a goal area and back to the origin. It is expected that the executor will make informed decisions about the mission, taking into account the navigational path, the vehicle subsystem health, and the sea environment, as well as the specific mission profile which is downloaded from an offboard mission planner. Heuristics for maneuvering, avoidance of uncharted obstacles, waypoint navigation, and reaction to emergencies (essentially the expert knowledge of a submarine captain) are required. Many of the vehicle subsystems are modeled as objects using the CLIPS Object Oriented Language (COOL) embedded in CLIPS 5.0. Also, truth maintenance is applied to the knowledge base to keep configurations updated.
Information is given in viewgraph form on the Space Station Freedom (SSF) Thermal Control System Automation Project (TCSAP). Topics covered include the assembly of the External Thermal Control System (ETCS); the ETCS functional schematic; the baseline Fault Detection, Isolation, and Recovery (FDIR), including the development of a knowledge based system (KBS) for application of rule based reasoning to the SSF ETCS; TCSAP software architecture; the High Fidelity Simulator architecture; the TCSAP Runtime Object Database (RODB) data flow; KBS functional architecture and logic flow; TCSAP growth and evolution; and TCSAP relationships.
In order to meet the stringent time-critical requirements for real-time man-in-the-loop flight simulation, computer processing operations including mathematical model computation and data input/output to the simulators must be deterministic and be completed in as short a time as possible. Personnel at NASA's Langley Research Center are currently developing the use of supercomputers for simulation mathematical model computation for real-time simulation. This, coupled with the use of an open systems software architecture, will advance the state-of-the-art in real-time flight simulation.
ESMOSS is a specialized software system for the construction of geometric descriptive and discrete analytical models of engine parts, components and substructures which can be transferred to finite element analysis programs such as NASTRAN. The software architecture of ESMOSS is designed in modular form with a central executive module through which the user controls and directs the development of the analytical model. Modules consist of a geometric shape generator, a library of discretization procedures, interfacing modules to join both geometric and discrete models, a deck generator to produce input for NASTRAN and a 'recipe' processor which generates geometric models from parametric definitions. ESMOSS can be executed both in interactive and batch modes. Interactive mode is considered to be the default mode and that mode will be assumed in the discussion in this document unless stated otherwise.
The Lawrence Livermore National Laboratory (LLNL) is a Department of Energy contractor, managed by the University of California since 1952. Major projects at the Laboratory include the Strategic Defense Initiative, nuclear weapon design, magnetic and laser fusion, laser isotope separation, and weather modeling. The Laboratory employs about 8,000 people. There are two major computer centers: The Livermore Computer Center and the National Energy Research Supercomputer Center. As we increase the computing capacity of LLNL systems and develop new applications, the need for archival capacity will increase. Rather than quantify that increase, I will discuss the hardware and software architectures that we will need to support advanced applications.
The viewgraphs of a discussion on Network Accessible Multi-terabyte Archive presented at the National Space Science Data Center (NSSDC) Mass Storage Workshop is included. Topics covered in the presentation include the rotary storage system (RSS) including RSS data access, data management, administration, and hardware and software architecture.
As the computing capacity of the Lawrence Livermore National Laboratory (LLNL) systems is increased and new applications are developed, the need for archival capacity will increase. The hardware and software architectures that will be needed to support advanced applications are discussed. Viewgraphs are included.
A navigation and control system was designed and implemented for an orbital autonomous rescue vehicle envisioned to retrieve astronauts or equipment in the case that they become disengaged from the space station. The rescue vehicle, termed the Extra-Vehicular Activity Retriever (EVAR), has an on-board inertial measurement unit ahd GPS receivers for self state estimation, a laser range imager (LRI) and cameras for object state estimation, and a data link for reception of space station state information. The states of the retriever and objects (obstacles and the target object) are estimated by inertial state propagation which is corrected via measurements from the GPS, the LRI system, or the camera system. Kalman filters are utilized to perform sensor fusion and estimate the state propagation errors. Control actuation is performed by a Manned Maneuvering Unit (MMU). Phase plane control techniques are used to control the rotational and translational state of the retriever. The translational controller provides station-keeping or motion along either Clohessy-Wiltshire trajectories or straight line trajectories in the LVLH frame of any sufficiently observed object or of the space station. The software was used to successfully control a prototype EVAR on an air bearing floor facility, and a simulated EVAR operating in a simulated orbital environment. The design of the navigation system and the control system are presented. Also discussed are the hardware systems and the overall software architecture.
The scope of this report is limited to the following: (1) assessing the feasibility of the assumptions for crew productivity during the intra-vehicular activities and extra-vehicular activities; (2) estimating the appropriate level of automation and robotics to accomplish balanced man-machine, cost-effective operations in space; (3) identifying areas where conceptually different approaches to the use of people and machines can leverage the benefits of the scenarios; and (4) recommending modifications to scenarios or developing new scenarios that will improve the expected benefits. The FY89 special assessments are grouped into the five categories shown in the report. The high level system analyses for Automation & Robotics (A&R) and Human Performance (HP) were performed under the Case Studies Technology Assessment category, whereas the detailed analyses for the critical systems and high leverage development areas were performed under the appropriate operations categories (In-Space Vehicle Operations or Planetary Surface Operations). The analysis activities planned for the Science Operations technology areas were deferred to FY90 studies. The remaining activities such as analytic tool development, graphics/video demonstrations and intelligent communicating systems software architecture were performed under the Simulation & Validations category.
A generic software architecture has been developed for posttest diagnostics of rocket engines, and is presently being applied to the posttest analysis of the SSME. This investigation deals with the Systems Section module of the architecture, which is presently under development. Overviews of the manual SSME systems analysis process and the overall SSME diagnostic system architecture are presented.
Work on the Flight Telerobotic Service (FTS) since that reported in Leake (1991) is examined, and initial work on a Hubble servicing mission is outlined. A state-of-the-art force reflecting teleoperation system that uses torque control at the joints of the slave manipulator has been implemented. The master rate/slave damper mode proposed by Langley has proved to be a very efficient operational mode, allowing force reflection ratios up to one to one. A software architecture for real-time Ada robotics systems has been proposed, and implementation has been launched. This architecture builds on the lessons learned from NASA Standard Reference Model Architecture and the prototype FTS effort. The Capaciflector sensor has been integrated into the system, and it has been used to perform a basic berthing task autonomously.
The results of a technology survey conducted for the NASA/JSC by the CSDL during Phase 1 of the NASA Advanced Information Processing System (AIPS) program at the CSDL are discussed. The purpose of the survey was to ensure that all technology relevant to the configuration, design, development, verification, implementation, and validation of an advanced information processing system, whether existing or under development and soon to be available, would be duly considered in the development of the AIPS. The emphasis in the survey was on technology items which were clearly relevant to the AIPS. Requirements were developed which guided the planning of contacts with the outside sources to be surveyed, and established practical limits on the scope and content of the Technology Survey. Subjects surveyed included architecture, software, hardware, methods for evaluation of reliability and performance, and methods for the verification of the AIPS design and the validation of the AIPS implementation. Survey requirements and survey results in each of these areas are presented, including analyses of the potential effects on the AIPS development process of using or not using the surveyed technology items. Another output of the survey was the identification of technology areas of particular relevance to the AIPS and for which further development, in some cases by the CSDL and in some cases by the NASA, would be fruitful. Appendices are provided in which are presented: (1) reports of some of the actual survey interactions with industrial and other outside information sources; (2) the literature list from the comprehensive literature survey which was conducted; (3) reduced-scale images of an excerpt ('Technology Survey' viewgraphs) from the set of viewgraphs used at the 14 April 1983 Preliminary Requirements Review by the CSDL for the NASA; and (4) reduced-scale images of the set of viewgraphs used in the AIPS Technology Survey Review presentation to the NASA monitors by the CSDL at the NASA Langley Research Center on 28 Sep. 1983.
This paper describes the development status of a prototype supervised intelligent robot for space application for purposes of (1) helping the crew of a spacecraft such as the Space Station with various tasks, such as holding objects and retrieving/replacing tools and other objects from/into storage, and (2) for purposes of retrieving detached objects, such as equipment or crew, that have become separated from their spacecraft. In addition to this set of tasks in this low-Earth-orbiting spacecraft environment, it is argued that certain aspects of the technology can be viewed as generic in approach, thereby offering insight into intelligent robots for other tasks and environments. Candidate software architectures and their key technical issues which enable real work in real environments to be accomplished safely and robustly are addressed. Results of computer simulations of grasping floating objects are presented. Also described are characterization results on the usable reduced gravity environment in an aircraft flying parabola (to simulate weightlessness) and results on hardware performance there. These results show it is feasible to use that environment for evaluative testing of dexterous grasping based on real-time vision of freely rotating and translating objects.
In order to meet the stringent time-critical requirements for real-time man-in-the-loop flight simulation, computer processing operations must be deterministic and be completed in as short a time as possible. This includes simulation mathematical model computational and data input/output to the simulators. In 1986, in response to increased demands for flight simulation performance, personnel at NASA's Langley Research Center (LaRC), working with the contractor, developed extensions to a standard input/output system to provide for high bandwidth, low latency data acquisition and distribution. The Computer Automated Measurement and Control technology (IEEE standard 595) was extended to meet the performance requirements for real-time simulation. This technology extension increased the effective bandwidth by a factor of ten and increased the performance of modules necessary for simulator communications. This technology is being used by more than 80 leading technological developers in the United States, Canada, and Europe. Included among the commercial applications of this technology are nuclear process control, power grid analysis, process monitoring, real-time simulation, and radar data acquisition. Personnel at LaRC have completed the development of the use of supercomputers for simulation mathematical model computational to support real-time flight simulation. This includes the development of a real-time operating system and the development of specialized software and hardware for the CAMAC simulator network. This work, coupled with the use of an open systems software architecture, has advanced the state of the art in real time flight simulation. The data acquisition technology innovation and experience with recent developments in this technology are described.
This paper presents an overview of the proposed Lyndon B. Johnson Space Center (JSC) precompetitive, dual-use technology investment project in robotics. New robotic technology in advanced robots, which can recognize and respond to their environments and to spoken human supervision so as to perform a variety of combined mobility and manipulation tasks in various sectors, is an obejective of this work. In the U.S. economy, such robots offer the benefits of improved global competitiveness in a critical industrial sector; improved productivity by the end users of these robots; a growing robotics industry that produces jobs and profits; lower cost health care delivery with quality improvements; and, as these 'intelligent' robots become acceptable throughout society, an increase in the standard of living for everyone. In space, such robots will provide improved safety, reliability, and productivity as Space Station evolves, and will enable human space exploration (by human/robot teams). The proposed effort consists of partnerships between manufacturers, universities, and JSC to develop working production prototypes of these robots by leveraging current development by both sides. Currently targeted applications are in the manufacturing, health care, services, and construction sectors of the U.S. economy and in the inspection, servicing, maintenance, and repair aspects of space exploration. But the focus is on the generic software architecture and standardized interfaces for custom modules tailored for the various applications allowing end users to customize a robot as PC users customize PC's. Production prototypes would be completed in 5 years under this proposal.