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At least 703 records · Page 39
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Test Results for Autonomous Assembly of Modular Space Structures

This paper presents test results for autonomous assembly of a modular space structure. A Universal Robots UR10e manipulator with a custom end-effector, known as the Grapple Tool, was used to join TriTruss structural modules. The TriTrusses and their assembly configuration were developed for an in-space assembled telescope conceptual design. The tests presented here were performed with a 1:2.8 dimensionally scaled version of the Tri-Trusses. Robot trajectories were generated autonomously using a sample-based motion planner and an a-priori worksite model. The test results verify the assembly concept of operations as well as the software requirements for the Grapple Tool. While the Grapple Tool used in the tests was designed for the 1:2.8 scale Tri-Trusses, it has the same actuators, software, and computation architecture as the version designed for the full scale structure. The test operations consist of picking up two TriTrusses from their stowed locations and joining them to a third TriTruss mounted on a test stand and joining them to each other. This constitutes the first three modules of the in-space assembled telescope conceptual design. The paper presents the robot behavioral architecture, the generated trajectories commanded, the actual trajectories of the robot, and actuator performance of the Grapple Tool.

test↗
NASA NTRS2015

PTC MathCAD and Workgroup Manager: Implementation in a Multi-Org System

In this presentation, the presenter will review what was done at Kennedy Space Center to deploy and implement PTC MathCAD and PTC Workgroup Manager in a multi-org system. During the presentation the presenter will explain how they configured PTC Windchill to create custom soft-types and object initialization rules for their custom numbering scheme and why they choose these methods. This presentation will also include how to modify the EPM default soft-type file in the PTC Windchill server codebase folder. The presenter will also go over the code used in a start up script to initiate PTC MathCAD and PTC Workgroup Manager in the proper order, and also set up the environment variables when running both PTC Workgroup Manager and PTC Creo. The configuration.ini file the presenter used will also be reviewed to show you how to set up the PTC Workgroup Manager and customized it to their user community. This presentation will be of interest to administrators trying to create a similar set-up in either a single org or multiple org system deployment. The big take away will be ideas and best practices learned through implementing this system, and the lessons learned what to do and not to do when setting up this configuration. Attendees will be exposed to several different sets of code used and that worked well and will hear some limitations on what the software can accomplish when configured this way.

Multi-Org System↗
NASA NTRS1990

Automating analog design: Taming the shrew

The pace of progress in the design of integrated circuits continues to amaze observers inside and outside of the industry. Three decades ago, a 50 transistor chip was a technological wonder. Fifteen year later, a 5000 transistor device would 'wow' the crowds. Today, 50,000 transistor chips will earn a 'not too bad' assessment, but it takes 500,000 to really leave an impression. In 1975 a typical ASIC device had 1000 transistors, took one year to first samples (and two years to production) and sold for about 5 cents per transistor. Today's 50,000 transistor gate array takes about 4 months from spec to silicon, works the first time, and sells for about 0.02 cents per transistor. Fifteen years ago, the single most laborious and error prone step in IC design was the physical layout. Today, most IC's never see the hand of a layout designer: and automatic place and route tool converts the engineer's computer captured schematic to a complete physical design using a gate array or a library of standard cells also created by software rather than by designers. CAD has also been a generous benefactor to the digital design process. The architect of today's digital systems creates the design using an RTL or other high level simulator. Then the designer pushes a button to invoke the logic synthesizer-optimizer tool. A fault analyzer checks the result for testability and suggests where scan based cells will improve test coverage. One obstinate holdout amidst this parade of progress is the automation of analog design and its reduction to semi-custom techniques. This paper investigates the application of CAD techniques to analog design.

Barlow, A.↗
NASA NTRS1996

Hypercars: The next industrial revolution

The auto industry -- one-seventh of the GNP, and the highest expression of the Iron Age -- is about to trigger the biggest transformation in industrial structure since the microchip. Ultralight cars molded from net-shape advanced composites can be several-fold lighter than present steel cars, yet safer, sportier, and more comfortable, durable, and beautiful. Modern hybrid-electric drives boost efficiency approximately 1.3-1.5x in heavy steel cars, but approximately 5-20x in ultralight, very slippery plafforms. Synergistically combined into ultralight-hybrid 'hypercars,' these elements can yield state-of-the-shelf family cars that average 150-300+ mi/gal -- twice that with state-of-the-art technologies -- yet can also be superior in all other respects, probably including cost: carbon-fiber monocoques can actually be cheaper to mass-produce that steel unibodies. Designing cars more like aircraft and less like tanks requires not only an approximately 400-500 kg curb mass and very low air and road drag, but also an aerospace philosophy of engineering integration. Mass, cost, and complexity turn out to compound with heavy hybrids but to decompound with ultralight hybrids, owing partly to radical simplification. Excellent aerodynamics, preferable including advanced techniques for passive boundary-layer control, will be the key to successful design integration. Transforming automaking is a competitive and environmental imperative, could form the nucleus of a green industrial Renaissance, and would enhance national security by, among other things, saving as much oil as OPEC now extracts. However, this transformation faces serious cultural barriers. For example, hypercars will be more like computers with wheels than like cars with chips -- they'll have an order of magnitude more code than today's cars -- but Detroit is not a software culture. Just the transition from stamped and welded steel to integrated and adhesive-joined synthetics is difficult enough. Nonetheless, hypercars are rapidly heading to market in the late 1990s, because approximately 25 current and intending automakers are eager to capture their potentially decisive competitive advantages -- including order-of-magnitude reductions in product cycle time, tooling cost, assembly effort, and parts count. Hypercars will succeed, and may well sweep the market, not because of mandates or subsidies, but because of manufacturers' quest for competitive advantage and customers' desire for better, smarter cars.

Lovins, Amory B.↗
NASA NTRS2015

Generalized Nanosatellite Avionics Testbed Lab

The Generalized Nanosatellite Avionics Testbed (G-NAT) lab at NASA Ames Research Center provides a flexible, easily accessible platform for developing hardware and software for advanced small spacecraft. A collaboration between the Mission Design Division and the Intelligent Systems Division, the objective of the lab is to provide testing data and general test protocols for advanced sensors, actuators, and processors for CubeSat-class spacecraft. By developing test schemes for advanced components outside of the standard mission lifecycle, the lab is able to help reduce the risk carried by advanced nanosatellite or CubeSat missions. Such missions are often allocated very little time for testing, and too often the test facilities must be custom-built for the needs of the mission at hand. The G-NAT lab helps to eliminate these problems by providing an existing suite of testbeds that combines easily accessible, commercial-offthe- shelf (COTS) processors with a collection of existing sensors and actuators.

Testing data and general test protocols↗
NASA NTRS2020

ISEE System Technical Report

The Immersive Simulations and Engineering Environment (ISEE) Laboratory at Kennedy Space Center is a tool used to assist with operation simulation, for Human Factors operation activities, assisting future missions. The simulations created are important because they ensure that simulated operations are performed for customers, to assist with requirements. Simultaneously, each simulation will allow stakeholders to determine any and all risk associated with the Human Factors involved in a specific assignment. My internship consists of multiple project elements. The first of which, was to assist the Integrations branch chief in developing a growth rate algorithm proof. The integral part of this project, involved learning to powerup and perform the operational procedures of the ISEE lab, capturing and creating characters used in the CAD model virtual environment. In doing so, this led to use the software to model and 3D print screw cap structures for mock-up. The structures will be used to manipulate weight change out used in mock-up design and construction. These structures will also be used in future mock-up models constructed in the lab.

Darryl A J Minor↗
NASA NTRS2020

Evolution of the Preliminary Fault Management Architecture and Design for the Psyche Mission

The Psyche Mission presents the first opportunity toexplore the largest metal asteroid in the solar system, (16)Psyche, which is believed to be the exposed core of a largerplanetesimal that was stripped of its rocky mantle throughmultiple collisions during early solar system formation. Themission was selected in January 2017 for a 2022 launch as partof NASA’s Discovery Program and is uniquely enabled by theintegration of a Solar Electric Propulsion (SEP) Chassisdelivered by Maxar Space Solutions with JPL’s core deepspace avionics, flight software, and fault managementarchitectures. One of the key design tasks is the development ofa fault management system capable of being responsive to theunique elements of the combined JPL and Maxar spacecraftarchitecture. This new design leverages the strengths of eachorganization, with Maxar delivering its well-proven highvoltage power bus and low-thrust electric propulsionsubsystem from its GEO communications satellite product line,and JPL delivering its deep space mission expertise and thehardware and software most critical to deep space missiondesign. The development of a robust low-thrust mission andthe integration of design philosophies and hardware from twoorganizations is not without its challenges though.A key challenge in the development of the Psyche faultmanagement architecture and design is in the integration ofdesign philosophies and hardware from JPL and Maxar. Atthe architecture level, Maxar GEO communications satellitesare developed under the premise of highly responsive groundin the loop for the resolution of anomalies, and theimplementation takes a fail-operational approach to minimizedown time for its customers. In contrast, a deep space missionmust be able to maintain safety with long periods of groundcommunication outage. Additionally, with no time-criticalevents after launch, the Psyche spacecraft will generally failsafe in the presence of anomalous conditions; specialconsideration is being given to this approach, however, tominimize the loss of electric propulsion thrust time, which iscritical to low-thrust missions. At the hardware level, thedetailed definition of interfaces between JPL and Maxarhardware presents a unique challenge in the development andflowdown of fault management requirements, the developmentand implementation of fault monitors and responses, and thedevelopment and verification of fault containment boundaries.This paper describes the evolution of the Psyche faultmanagement architecture and design from the concept studyinto the preliminary design phase, with a focus on the uniquechallenges associated with flying GEO communicationssatellite hardware in deep space, implementing a robust lowthrust mission, and the integration of design philosophies andhardware from JPL and Maxar. Details regarding how thesechallenges are addressed in the fault management design inorder to maximize heritage, leverage the strengths of eachorganization, and minimize risk across the design are alsodiscussed.

Marsh, Danielle↗
NASA NTRS2024

3D Scanning System to Assess Gravity-Dependent Body Shape Changes

The human body shows unique physiological and morphological changes when exposed to different gravity conditions, including muscle atrophy, fluid shift, spinal elongation, and body posture adjustments. Such changes need to be incorporated for human-system integration in the vehicle habitat, garment, and spacesuit designs, as inaccurate body measurements can result in suboptimal crew protection that can potentially decrease injury tolerance. However, the traditional linear measurements, such as stature, segment lengths or circumferences measured using a caliper or tape measure, often show limited consistency and are unable to capture the nonlinear characteristics of the human body. While 3D body scanning can provide significant advantages over linear measurements, the technologies have not been fully developed or customized for in-flight scanning. For ground laboratory use, several different scanner types are commercially available. However, in-flight scanning requires additional technical considerations, such as minimal scan time, simplified calibration, and sufficient capture volume. This work aims to develop a prototype 3-D body scanning system that is customized for in-flight use to scan crewmembers, with the configuration and performance optimized for detecting known gravity-dependent body shape and posture changes. A hardware system will be custom built using a network of commercial off-the-shelf 3D sensors. The sensor parameters and settings will be optimized to detect the targeted body shape changes, specifically using body manikins of which the shape and size are iteratively permuted to simulate the known changes by fluid shift and spinal elongation. The capture volume will be also matched for a range of body sizes from a 1st percentile female to 99th percentile male. Unintentional body motions or floating in microgravity will be also simulated and incorporated. A data acquisition software will be developed for efficient in-flight operations with minimal overhead and easy-to-use user interface. A simplified calibration procedure will be designed for robust scanning against frequent vibration or unexpected sensor position shifts. The system will be tested in the ground laboratory for accuracy and reliability against a reference scanning system. New anthropometry measurements will be also identified to sensitively capture the gravity dependent body shape changes, in addition to the traditional anthropometry measurements. A novel landmark-based technique will be tested for consistent anthropometry measurements across posture variations. If successfully developed and deployed, the new system is expected to provide previously unavailable body shape and size data from different gravitational environments, including 0-g, 1/6-g, and 1-g. Such data can improve suit fit, habitat design, exercise efficacy quantification and sizing of orthostatic intolerance garments.

K H Kim↗
NASA NTRS2024

3D Scanning System to Assess Gravity-Dependent Body Shape Changes

The human body shows unique physiological and morphological changes when exposed to different gravity conditions, including muscle atrophy, fluid shift, spinal elongation, and body posture adjustments. Such changes need to be incorporated for human-system integration in the vehicle habitat, garment, and spacesuit designs, as inaccurate body measurements can result in suboptimal crew protection that can potentially decrease injury tolerance. However, the traditional linear measurements, such as stature, segment lengths or circumferences measured using a caliper or tape measure, often show limited consistency and are unable to capture the nonlinear characteristics of the human body. While 3D body scanning can provide significant advantages over linear measurements, the technologies have not been fully developed or customized for in-flight scanning. For ground laboratory use, several different scanner types are commercially available. However, in-flight scanning requires additional technical considerations, such as minimal scan time, simplified calibration, and sufficient capture volume. This work aims to develop a prototype 3-D body scanning system that is customized for in-flight use to scan crewmembers, with the configuration and performance optimized for detecting known gravity-dependent body shape and posture changes. A hardware system will be custom built using a network of commercial off-the-shelf 3D sensors. The sensor parameters and settings will be optimized to detect the targeted body shape changes, specifically using body manikins of which the shape and size are iteratively permuted to simulate the known changes by fluid shift and spinal elongation. The capture volume will be also matched for a range of body sizes from a 1st percentile female to 99th percentile male. Unintentional body motions or floating in microgravity will be also simulated and incorporated. A data acquisition software will be developed for efficient in-flight operations with minimal overhead and easy-to-use user interface. A simplified calibration procedure will be designed for robust scanning against frequent vibration or unexpected sensor position shifts. The system will be tested in the ground laboratory for accuracy and reliability against a reference scanning system. New anthropometry measurements will be also identified to sensitively capture the gravity dependent body shape changes, in addition to the traditional anthropometry measurements. A novel landmark-based technique will be tested for consistent anthropometry measurements across posture variations. If successfully developed and deployed, the new system is expected to provide previously unavailable body shape and size data from different gravitational environments, including 0-g, 1/6-g, and 1-g. Such data can improve suit fit, habitat design, exercise efficacy quantification and sizing of orthostatic intolerance garments.

K H Kim↗
NASA NTRS1984

Standardization in software conversion of (ROM) estimating

Technical problems and their solutions comprise by far the majority of work involved in space simulation engineering. Fixed price contracts with schedule award fees are becoming more and more prevalent. Accurate estimation of these jobs is critical to maintain costs within limits and to predict realistic contract schedule dates. Computerized estimating may hold the answer to these new problems, though up to now computerized estimating has been complex, expensive, and geared to the business world, not to technical people. The objective of this effort was to provide a simple program on a desk top computer capable of providing a Rough Order of Magnitude (ROM) estimate in a short time. This program is not intended to provide a highly detailed breakdown of costs to a customer, but to provide a number which can be used as a rough estimate on short notice. With more debugging and fine tuning, a more detailed estimate can be made.

Roat, G. H.↗
NASA NTRS1992

Repository-based software engineering program: Concept document

This document provides the context for Repository-Based Software Engineering's (RBSE's) evolving functional and operational product requirements, and it is the parent document for development of detailed technical and management plans. When furnished, requirements documents will serve as the governing RBSE product specification. The RBSE Program Management Plan will define resources, schedules, and technical and organizational approaches to fulfilling the goals and objectives of this concept. The purpose of this document is to provide a concise overview of RBSE, describe the rationale for the RBSE Program, and define a clear, common vision for RBSE team members and customers. The document also provides the foundation for developing RBSE user and system requirements and a corresponding Program Management Plan. The concept is used to express the program mission to RBSE users and managers and to provide an exhibit for community review.

Source record↗
NASA NTRS1993

Volume serving and media management in a networked, distributed client/server environment

The E-Systems Modular Automated Storage System (EMASS) is a family of hierarchical mass storage systems providing complete storage/'file space' management. The EMASS volume server provides the flexibility to work with different clients (file servers), different platforms, and different archives with a 'mix and match' capability. The EMASS design considers all file management programs as clients of the volume server system. System storage capacities are tailored to customer needs ranging from small data centers to large central libraries serving multiple users simultaneously. All EMASS hardware is commercial off the shelf (COTS), selected to provide the performance and reliability needed in current and future mass storage solutions. All interfaces use standard commercial protocols and networks suitable to service multiple hosts. EMASS is designed to efficiently store and retrieve in excess of 10,000 terabytes of data. Current clients include CRAY's YMP Model E based Data Migration Facility (DMF), IBM's RS/6000 based Unitree, and CONVEX based EMASS File Server software. The VolSer software provides the capability to accept client or graphical user interface (GUI) commands from the operator's console and translate them to the commands needed to control any configured archive. The VolSer system offers advanced features to enhance media handling and particularly media mounting such as: automated media migration, preferred media placement, drive load leveling, registered MediaClass groupings, and drive pooling.

Herring, Ralph H.↗
NASA NTRS2020

Electrospraying for Precision Delivery of Water and Nutrients for Aeroponics in Microgravity

Developed an enclosure with a custom high voltage nozzle that electrosprays wire "roots" with milliliters (mL) of water in real time by measuring the charge sprayed onto the roots. It uses the spray’s charge to mass from previous measurements with the same nozzle (and the density of water) to convert the display to volume. To deliver water to the nozzle consistently and programmatically, the syringe pump performed the best for experiments because the diaphragm pump created a stuttered flow and the pressurized reservoir’s pressure controller was more complex than the syringe pump’s commercial LabVIEW software that direct controls flow rate.

Joel D Malissa↗
NASA NTRS1995

PC Software graphics tool for conceptual design of space/planetary electrical power systems

This paper describes the Decision Support System (DSS), a personal computer software graphics tool for designing conceptual space and/or planetary electrical power systems. By using the DSS, users can obtain desirable system design and operating parameters, such as system weight, electrical distribution efficiency, and bus power. With this tool, a large-scale specific power system was designed in a matter of days. It is an excellent tool to help designers make tradeoffs between system components, hardware architectures, and operation parameters in the early stages of the design cycle. The DSS is a user-friendly, menu-driven tool with online help and a custom graphical user interface. An example design and results are illustrated for a typical space power system with multiple types of power sources, frequencies, energy storage systems, and loads.

Truong, Long V.↗
NASA NTRS1994

COSMIC monthly progress report

Activities of the Computer Software Management and Information Center (COSMIC) are summarized for the month of May 1994. Tables showing the current inventory of programs available from COSMIC are presented and program processing and evaluation activities are summarized. Nine articles were prepared for publication in the NASA Tech Brief Journal. These articles (included in this report) describe the following software items: (1) WFI - Windowing System for Test and Simulation; (2) HZETRN - A Free Space Radiation Transport and Shielding Program; (3) COMGEN-BEM - Composite Model Generation-Boundary Element Method; (4) IDDS - Interactive Data Display System; (5) CET93/PC - Chemical Equilibrium with Transport Properties, 1993; (6) SDVIC - Sub-pixel Digital Video Image Correlation; (7) TRASYS - Thermal Radiation Analyzer System (HP9000 Series 700/800 Version without NASADIG); (8) NASADIG - NASA Device Independent Graphics Library, Version 6.0 (VAX VMS Version); and (9) NASADIG - NASA Device Independent Graphics Library, Version 6.0 (UNIX Version). Activities in the areas of marketing, customer service, benefits identification, maintenance and support, and dissemination are also described along with a budget summary.

Source record↗
NASA NTRS1994

A strategy for electronic dissemination of NASA Langley technical publications

To demonstrate NASA Langley Research Center's relevance and to transfer technology to external customers in a timely and efficient manner, Langley has formed a working group to study and recommend a course of action for the electronic dissemination of technical reports (EDTR). The working group identified electronic report requirements (e.g., accessibility, file format, search requirements) of customers in U.S. industry through numerous site visits and personal contacts. Internal surveys were also used to determine commonalities in document preparation methods. From these surveys, a set of requirements for an electronic dissemination system was developed. Two candidate systems were identified and evaluated against the set of requirements: the Full-Text Electronic Documents System (FEDS), which is a full-text retrieval system based on the commercial document management package Interleaf, and the Langley Technical Report Server (LTRS), which is a Langley-developed system based on the publicly available World Wide Web (WWW) software system. Factors that led to the selection of LTRS as the vehicle for electronic dissemination included searching and viewing capability, current system operability, and client software availability for multiple platforms at no cost to industry. This report includes the survey results, evaluations, a description of the LTRS architecture, recommended policy statement, and suggestions for future implementations.

Roper, Donna G.↗
NASA NTRS2010

Configurable Multi-Purpose Processor

Advancements in technology have allowed the miniaturization of systems used in aerospace vehicles. This technology is driven by the need for next-generation systems that provide reliable, responsive, and cost-effective range operations while providing increased capabilities such as simultaneous mission support, increased launch trajectories, improved launch, and landing opportunities, etc. Leveraging the newest technologies, the command and telemetry processor (CTP) concept provides for a compact, flexible, and integrated solution for flight command and telemetry systems and range systems. The CTP is a relatively small circuit board that serves as a processing platform for high dynamic, high vibration environments. The CTP can be reconfigured and reprogrammed, allowing it to be adapted for many different applications. The design is centered around a configurable field-programmable gate array (FPGA) device that contains numerous logic cells that can be used to implement traditional integrated circuits. The FPGA contains two PowerPC processors running the Vx-Works real-time operating system and are used to execute software programs specific to each application. The CTP was designed and developed specifically to provide telemetry functions; namely, the command processing, telemetry processing, and GPS metric tracking of a flight vehicle. However, it can be used as a general-purpose processor board to perform numerous functions implemented in either hardware or software using the FPGA s processors and/or logic cells. Functionally, the CTP was designed for range safety applications where it would ultimately become part of a vehicle s flight termination system. Consequently, the major functions of the CTP are to perform the forward link command processing, GPS metric tracking, return link telemetry data processing, error detection and correction, data encryption/ decryption, and initiate flight termination action commands. Also, the CTP had to be designed to survive and operate in a launch environment. Additionally, the CTP was designed to interface with the WFF (Wallops Flight Facility) custom-designed transceiver board which is used in the Low Cost TDRSS Transceiver (LCT2) also developed by WFF. The LCT2 s transceiver board demodulates commands received from the ground via the forward link and sends them to the CTP, where they are processed. The CTP inputs and processes data from the inertial measurement unit (IMU) and the GPS receiver board, generates status data, and then sends the data to the transceiver board where it is modulated and sent to the ground via the return link. Overall, the CTP has combined processing with the ability to interface to a GPS receiver, an IMU, and a pulse code modulation (PCM) communication link, while providing the capability to support common interfaces including Ethernet and serial interfaces boarding a relatively small-sized, lightweight package.

Valencia, J. Emilio↗
NASA NTRS2008

Problem Reporting System

The Problem Reporting System (PRS) is a Web application, running on two Web servers (load-balanced) and two database servers (RAID-5), which establishes a system for submission, editing, and sharing of reports to manage risk assessment of anomalies identified in NASA's flight projects. PRS consolidates diverse anomaly-reporting systems, maintains a rich database set, and incorporates a robust engine, which allows tracking of any hardware, software, or paper process by configuring an appropriate life cycle. Global and specific project administration and setup tools allow lifecycle tailoring, along with customizable controls for user, e-mail, notifications, and more. PRS is accessible via the World Wide Web for authorized user at most any location. Upon successful log-in, the user receives a customizable window, which displays time-critical 'To Do' items (anomalies requiring the user s input before the system moves the anomaly to the next phase of the lifecycle), anomalies originated by the user, anomalies the user has addressed, and custom queries that can be saved for future use. Access controls exist depending on a user's role as system administrator, project administrator, user, or developer, and then, further by association with user, project, subsystem, company, or item with provisions for business-to-business exclusions, limitations on access according to the covert or overt nature of a given project, all with multiple layers of filtration, as needed. Reporting of metrics is built in. There is a provision for proxy access (in which the user may choose to grant one or more other users to view screens and perform actions as though they were the user, during any part of a tracking life cycle - especially useful during tight build schedules and vacations to keep things moving). The system also provides users the ability to have an anomaly link to or notify other systems, including QA Inspection Reports, Safety, GIDEP (Government-Industry Data Exchange Program) Alert, Corrective Actions, and Lessons Learned. The PRS tracking engine was designed as a very extensible and scalable system, able to support additional applications, with future development possibilities already discussed, including Incident Surprise Anomalies (for anomalies occurring during Operations phases of NASA Flight projects), GIDEP and NASA Alerts, and others.

Potter, Don↗