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A new software tool, Caesy, is described. This tool provides a strongly typed programming environment for research in the development of algorithms and software for computer-aided control system design. A description of the user language and its implementation as they currently stand are presented along with a description of work in progress and areas of future work.
Transportable Applications Environment (TAE), a Goddard Space Flight Center developed software management system, organizes multiple computer programs by providing user interface development tools and a stable framework for a system. It binds applications into an easily operated whole and interfaces with users. The program also lowers system development and software conversion costs by providing software and structures for commonly recurring user requirements. Originally developed to support image processing and remote sensing applications, TAE is now used in scientific analysis and defense systems, and as a teaching tool by private industry and government. A support office assists users. New development areas are anticipated.
This paper discusses technologies and software tools that are being implemented in a software toolkit currently under development at NASA Glenn Research Center. Its purpose is to help study the effects of icing on airfoil performance and assist with the aerodynamic simulation process which consists of characterization and modeling of ice geometry, application of block topology and grid generation, and flow simulation. Tools and technologies for each task have been carefully chosen based on their contribution to the overall process. For the geometry characterization and modeling, we have chosen an interactive rather than automatic process in order to handle numerous ice shapes. An Appendix presents features of a software toolkit developed to support the interactive process. Approaches taken for the generation of block topology and grids, and flow simulation, though not yet implemented in the software, are discussed with reasons for why particular methods are chosen. Some of the issues that need to be addressed and discussed by the icing community are also included.
A computer program has been written as a tool for developing optical pulse-position- modulation (PPM) receivers in which photodetector outputs are fed to analog-to-digital converters (ADCs) and all subsequent signal processing is performed digitally. The program can be used, for example, to simulate an all-digital version of the PPM receiver described in Parallel Processing of Broad-Band PPM Signals (NPO-40711), which appears elsewhere in this issue of NASA Tech Briefs. The program can also be translated into a design for digital PPM receiver hardware. The most notable innovation embodied in the software and the underlying PPM-reception concept is a digital processing subsystem that performs synchronization of PPM time slots, even though the digital processing is, itself, asynchronous in the sense that no attempt is made to synchronize it with the incoming optical signal a priori and there is no feedback to analog signal processing subsystems or ADCs. Functions performed by the software receiver include time-slot synchronization, symbol synchronization, coding preprocessing, and diagnostic functions. The program is written in the MATLAB and Simulink software system. The software receiver is highly parameterized and, hence, programmable: for example, slot- and symbol-synchronization filters have programmable bandwidths.
Set of three reports describes work on Protoflight Manipulator Assembly (PFMA). "Performance Characteristics of Protoflight Manipulator Assembly" presents parameters of PFMA after refurbishment of operating components. "End Effector and Task Board Development for the Protoflight Manipulator Assembly" describes special tools and adaptations allowing PFMA to be used for servicing equipment. "Modular Software Development for the Protoflight Manipulator Assembly" documents interface and control software for PFMA.
As NASA supports International Space Station assembly complete operations through 2020 (or later) and prepares for future human exploration programs, there is additional emphasis in the manned spaceflight program to find more efficient and effective ways of providing the ground-based mission support. Since 2006 this search for improvement has led to a significant cross-fertilization between the NASA advanced software development community and the manned spaceflight operations community. A variety of mission operations systems and tools have been developed over the past decades as NASA has operated the Mars robotic missions, the Space Shuttle, and the International Space Station. NASA Ames Research Center has been developing and applying its advanced intelligent systems research to mission operations tools for both unmanned Mars missions operations since 2001 and to manned operations with NASA Johnson Space Center since 2006. In particular, the fundamental advanced software development work under the Exploration Technology Program, and the experience and capabilities developed for mission operations systems for the Mars surface missions, (Spirit/Opportunity, Phoenix Lander, and MSL) have enhanced the development and application of advanced mission operation systems for the International Space Station and future spacecraft. This paper provides an update on the status of the development and deployment of a variety of intelligent systems technologies adopted for manned mission operations, and some discussion of the planned work for Autonomous Mission Operations in future human exploration. We discuss several specific projects between the Ames Research Center and the Johnson Space Centers Mission Operations Directorate, and how these technologies and projects are enhancing the mission operations support for the International Space Station, and supporting the current Autonomous Mission Operations Project for the mission operation support of the future human exploration programs.
Formal verfication and simulation are powerful tools to validate requirements against complex systems. [Problem] Requirements are developed in early stages of the software lifecycle and are typically written in ambiguous natural language. There is a gap between such requirements and formal notations that can be used by verification tools, and lack of support for proper association of requirements with software artifacts for verification. [Principal idea] We propose to write requirements in an intuitive, structured natural language with formal semantics, and to support formalization and model/code verification as a smooth, well-integrated process. [Contribution] We have developed an end-to-end, open source requirements analysis framework that checks Simulink models against requirements written in structured natural language. Our framework is built in the Formal Requirements Elicitation Tool (fret); we use fret's requirements language named fretish, and formalization of fretish requirements in temporal logics. Our proposed framework contributes the following features: 1) automatic extraction of Simulink model information and association of fretish requirements with target model signals and components; 2) translation of temporal logic formulas into synchronous dataflow cocospec specifications as well as Simulink monitors, to be used by verification tools; we establish correctness of our translation through extensive automated testing; 3) interpretation of counterexamples produced by verification tools back at requirements level. These features support a tight integration and feedback loop between high level requirements and their analysis. We demonstrate our approach on a major case study: the Ten Lockheed Martin Cyber-Physical, aerospace-inspired challenge problems.
SMU personnel formed a portion of the overall “Time Integration” team within the FASTMath SciDAC-5 Institute, and we interacted very closely with team members from collaborating institutions. The major goals of our team within the FASTMath institute may be categorized into two groups: the development of advanced and application-aware time integration methods and software, and close interactions with DOE application scientists to facilitate their use of these new methods and software. The two goals are intimately linked, since our research and development of novel tools is informed by the needs of our application partners, who in turn benefit from subsequent mathematical and software advances. While the SMU personnel collaborated with the rest of the Time Integration FASTMath team on most of our shared deliverables within the larger FASTMath institute, SMU personnel primarily contributed to the following subset of those goals: ● expanding capabilities for higher-order and solve-decoupled multirate methods, ● enhancing support for temporal adaptivity within multirate methods, and ● adding structure-aware time integration methods. Each of these goals focused both on intellectual contributions through journal articles or research presentations, and on enhancements to the open-source SUNDIALS library of time integrators and nonlinear solvers, of which the SMU PI Reynolds is a core developer.
Over the past 30 years climate models have evolved from relatively simple representations of a few atmospheric processes to complex multi-disciplinary system models which incorporate physics from bottom of the ocean to the mesopause and are used for seasonal to multi-million year timescales. Computer infrastructure over that period has gone from punchcard mainframes to modern parallel clusters. Constraints of working within an ever evolving research code mean that most software changes must be incremental so as not to disrupt scientific throughput. Unfortunately, programming methodologies have generally not kept pace with these challenges, and existing implementations now present a heavy and growing burden on further model development as well as limiting flexibility and reliability. Opportunely, advances in software engineering from other disciplines (e.g. the commercial software industry) as well as new generations of powerful development tools can be incorporated by the model developers to incrementally and systematically improve underlying implementations and reverse the long term trend of increasing development overhead. However, these methodologies cannot be applied blindly, but rather must be carefully tailored to the unique characteristics of scientific software development. We will discuss the need for close integration of software engineers and climate scientists to find the optimal processes for climate modeling.
This software is used to locate Earth-science satellite data and climate-model analysis outputs in space and time. This enables the direct comparison of any set of data with different spatial and temporal resolutions. It is written in three separate modules that are clearly separated for their functionality and interface with other modules. This enables a fast development of supporting any new data set. In this updated version of the tool, several new front ends are developed for new products. This software finds co-locatable data pairs for given sets of data products and creates new data products that share the same spatial and temporal coordinates. This facilitates the direct comparison between the two heterogeneous datasets and the comprehensive and synergistic use of the datasets.
The software developed by the IPAD project, a new and very powerful tool for the implementation of integrated Computer Aided Design (CAD) systems in the aerospace engineering community, is discussed. The IPAD software is a tool and, as such, can be well applied or misapplied in any particular environment. The many benefits of an integrated CAD system are well documented, but there are few such systems in existence, especially in the mechanical engineering disciplines, and therefore little available experience to guide the implementor.
Research in the software engineering community continues to lead to new development techniques that encompass processes, methods and tools. However, a number of obstacles impede their infusion into software deveopment practices. This paper describes an ongoing effort conducted by a software engineering research infusion team established by NASA's Software Engineering Intiative to overcome these obstacles.
For the x-ray observatory ROSAT, data from survey and pointed mission phases taken with different focal plane instruments and according to a complex mission timeline have to be handled. Data analysis therefore puts high demands on appropriate software tools. With EXSAS - the Extended Scientific Analysis System developed with an effort of 20 man years by the German ROSAT Scientific Data Center - a comfortable system for the reduction of data from the ROSAT x-ray and XUV instruments has been made available. EXSAS comprises a large collection of application modules as typically required in analyzing data of this wavelength regime and runs as a specific context in the wide-spread ESO-MIDAS environment. EXSAS, completely written in FORTRAN 77, takes full advantage of all the standards used in MIDAS and therefore, reflects the same portability (different UNIX installations and VMS). If required, the FORTRAN code also enables users to adapt the software in an easy way to their specific needs. To maintain independence from the specifics of different operating systems also on the data input side, all ROSAT data redistributed in the widely accepted FITS format. Although EXSAS has been developed specifically for data analysis of the ROSAT instruments, its structural design is sufficiently general to serve equally well also data from other X-ray and XUV instruments. EXSAS analysis modules are grouped into 4 application packages dealing with Data Preparation and Instrument Correction, Spatial Analysis, Spectral Analysis and Timing Analysis. A special EXSAS header, read and updated by each application, maintains the general information transfer on the origin, the history and the parameter space of the data stored in tables and images. About 100 genuine commands (most of which offer several additional options) allow to interactively explore the functionality of the system. Up to now 40 institutes all over the world have requested the EXSAS software. Maintenance and regular updates of the software and the comprehensive documentation are provided by the ROSAT Scientific Data Center at Garching.
NASA's Aviation Safety Program in the NASA Aeronautics Research Mission Directorate, which seeks to make aviation safer by developing tools for flight data analysis and interpretation and then by transferring these tools to the aviation industry, sponsored the development of Morning Report software. The software, created at Ames Research Center with the assistance of the Pacific Northwest National Laboratory, seeks to detect atypicalities without any predefined parameters-it spots deviations and highlights them. In 2004, Sagem Avionics Inc. entered a licensing agreement with NASA for the commercialization of the Morning Report software, and also licensed the NASA Aviation Data Integration System (ADIS) tool, which allows for the integration of data from disparate sources into the flight data analysis process. Sagem Avionics incorporated the Morning Report tool into its AGS product, a comprehensive flight operations monitoring system that helps users detect irregular or divergent practices, technical flaws, and problems that might develop when aircraft operate outside of normal procedures. Sagem developed AGS in collaboration with airlines, so that the system takes into account their technical evolutions and needs, and each airline is able to easily perform specific treatments and to build its own flight data analysis system. Further, the AGS is designed to support any aircraft and flight data recorders.
In this paper, we have introduced a comprehensive method for enterprise modeling that addresses the three important aspects of how an organization goes about its business. FirstEP includes infrastructure modeling, information modeling, and process modeling notations that are intended to be easy to learn and use. The notations stress the use of straightforward visual languages that are intuitive, syntactically simple, and semantically rich. ProSLCSE will be developed with automated tools and services to facilitate enterprise modeling and process enactment. In the spirit of FirstEP, ProSLCSE tools will also be seductively easy to use. Achieving fully managed, optimized software development and support processes will be long and arduous for most software organizations, and many serious problems will have to be solved along the way. ProSLCSE will provide the ability to document, communicate, and modify existing processes, which is the necessary first step.
Increasing environmental legislation has brought about the development of many new environmental databases and software application packages to aid in the quest for environmental compliance. These databases and software packages are useful tools and applicable to a wide range of environmental areas from atmospheric modeling to materials replacement technology. The great abundance of such products and services can be very overwhelming when trying to identify the tools which best meet specific needs. This paper will discuss the types of environmental databases and software packages available. This discussion will also encompass the affected environmental areas of concern, product capabilities, and hardware requirements for product utilization.
This report documents the work done under a NASA sponsored contract to transition to industry technologies developed under the NASA Lewis Research Center IMPAC (Integrated Methodology for Propulsion and Airframe Control) program. The critical steps in IMPAC are exercised on an example integrated flight/propulsion control design for linear airframe/engine models of a conceptual STOVL (Short Take-Off and Vertical Landing) aircraft, and MATRIXX (TM) executive files to implement each step are developed. The results from the example study are analyzed and lessons learned are listed along with recommendations that will improve the application of each design step. The end product of this research is a set of software requirements for developing a user-friendly control design tool which will automate the steps in the IMPAC methodology. Prototypes for a graphical user interface (GUI) are sketched to specify how the tool will interact with the user, and it is recommended to build the tool around existing computer aided control design software packages.
Noise from aircraft in the airport vicinity is one of the leading aviation-induced environmental issues. The FAA developed the Integrated Noise Model (INM) and its replacement Aviation Environmental Design Tool (AEDT) software to assess noise impact resulting from all aviation activities. However, a software tool is needed that is simple to use for terminal route modification, quick and reasonably accurate for preliminary noise impact evaluation and flexible to be used for iterative design of optimal noise-abatement terminal routes. In this paper, we extend our previous work on developing a noise-abatement terminal approach route design tool, named AIRNOISE, to satisfy this criterion. First, software efficiency has been significantly increased by over tenfold using the C programming language instead of MATLAB. Moreover, a state-of-the-art high performance GPU-accelerated computing module is implemented that was tested to be hundreds time faster than the C implementation. Secondly, a Graphical User Interface (GUI) was developed allowing users to import current terminal approach routes and modify the routes interactively to design new terminal approach routes. The corresponding noise impacts are then calculated and displayed in the GUI in seconds. Finally, AIRNOISE was applied to Baltimore-Washington International Airport terminal approach route to demonstrate its usage.