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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS2000

NASA's 3D Flight Computer for Space Applications

The New Millennium Program (NMP) Integrated Product Development Team (IPDT) for Microelectronics Systems was planning to validate a newly developed 3D Flight Computer system on its first deep-space flight, DS1, launched in October 1998. This computer, developed in the 1995-97 time frame, contains many new computer technologies previously never used in deep-space systems. They include: advanced 3D packaging architecture for future low-mass and low-volume avionics systems; high-density 3D packaged chip-stacks for both volatile and non-volatile mass memory: 400 Mbytes of local DRAM memory, and 128 Mbytes of Flash memory; high-bandwidth Peripheral Component Interface (Per) local-bus with a bridge to VME; high-bandwidth (20 Mbps) fiber-optic serial bus; and other attributes, such as standard support for Design for Testability (DFT). Even though this computer system did not complete on time for delivery to the DS1 project, it was an important development along a technology roadmap towards highly integrated and highly miniaturized avionics systems for deep-space applications. This continued technology development is now being performed by NASA's Deep Space System Development Program (also known as X2000) and within JPL's Center for Integrated Space Microsystems (CISM).

Alkalai, Leon↗
NASA NTRS2000

NASA/University JOint VEnture (JOVE) Program. VIXEN(tm): Object-Oriented, Technology-Adaptive, Virtual Information Exchange Environment

Vixen is a collection of enabling technologies for uninhibited distributed object computing. In the Spring of 1995 when Vixen was proposed, it was an innovative idea very much ahead of its time. But today the technologies proposed in Vixen have become standard technologies for Enterprise Computing. Sun Microsystems J2EE/EJB specifications, among others, are independently proposed technologies of the Vixen type. I have brought Vixen completely under the J2EE standard in order to maximize interoperability and compatibility with other computing industry efforts. Vixen and the Enterprise JavaBean (EJB) Server technologies are now practically identical; OIL, another Vixen technology, and the Java Messaging System (JMS) are practically identical; and so on. There is no longer anything novel or patentable in the Vixen work performed under this grant. The above discussion, notwithstanding, my independent development of Vixen has significantly helped me, my university, my students and the local community. The undergraduate students who worked with me in developing Vixen have enhanced their expertise in what has become the cutting edge technology of their industry and are therefore well positioned for lucrative employment opportunities in the industry. My academic department has gained a new course: "Multi-media System Development", which provides a highly desirable expertise to our students for employment in any enterprise today. The many Outreach Programs that I conducted during this grant period have exposed local Middle School students to the contributions that NASA is making in our society as well as awakened desires in many such students for careers in Science and Technology. I have applied Vixen to the development of two software packages: (a) JAS: Joshua Application Server - which allows a user to configure an EJB Server to serve a J2EE compliant application over the world wide web; (b) PCM: Professor Course Manager: a J2EE compliant application for configuring a course for distance learning. These types of applications are, however, generally available in the industry today.

Anyiwo, Joshua C.↗
NASA NTRS1999

Thin Film Li Ion Microbatteries for NASA Applications

Rechargeable thin film microbatteries have recently become the topic of widespread research for use in low power applications such as battery-backed CMOS memory, miniaturized implantable medical devices and smart cards. In particular, the Center for Integrated Space Microsystems (CISM) at NASA's Jet Propulsion Laboratory has interest in applying this technology for secondary power systems in miniaturized satellites, microsensors, microactuators and other remote MEMS applications. The general requirements of the microbatteries for these applications are high specific energy, wide range of temperature stability. low self-discharge rate, and flexibility of cell design. The thin film Li ion materials system using LiCoO2(LiPO(x)N(1-x))SnO is expected to fulfill these requirements.

West, W. C.↗
NASA NTRS2001

Electrically Isolating Subsystems in SOAC Technologies

Integrated circuit fabrication technology has evolved to the point that it is possible to construct complete systems, including power, data processing, and communications, on a single chip. Such System-on-a-chip (SOAC) technologies can enable drastic reductions in spacecraft size and weight, lowering the cost of missions and presenting new mission opportunities. This paper overviews some key enabling technologies unique to the needs of spacecraft for outer-planet exploration and missions requiring extreme resistance to radiation such as Europa orbiters and Europa Landers. The work is being carried out by Kansas State University (KSU) under direction of the Center for Integrated Space Microsystems (CISM) at NASA's Jet Propulsion Laboratory. Additional information is contained in the original extended abstract.

Boyd, R. M.↗
NASA NTRS2001

Integration of Passive Components for Spacecraft Avionics

The NASA roadmap outlining future deep space missions to Europa and other outer planetary destinations calls for continued reductions in the mass and volume of the spacecraft avionics. Spacecraft power electronics, including the power switches and converters, remain difficult to miniaturize due to the need for large numbers of discrete passive components such as resistors, capacitors, inductors and transformers. As part of the System-on-a-chip program at the Center for Integrated Space Microsystems and at the University of Arkansas, we are working to develop integrated or embedded passive components geared specifically for use in power management and distribution (PMAD) in future avionics over the next five to ten years. This will not only enable a scaling down of the power subsystems, but will make possible new architectures such as "distributed" PMAD. Additional information is contained in the original extended abstract.

Brandon, E. J.↗
NASA NTRS2001

A Multi-Mission Testbed for Advanced Technologies

The mission of the Center for Space Integrated Microsystem (CSIM) at the Jet Propulsion Laboratory is to develop advanced avionics systems for future deep space missions. The Advanced Micro Spacecraft (AMS) task is building a multi-mission testbed facility to enable the infusion of CSIM technologies into future missions. The testbed facility will also perform experimentation for advanced avionics technologies and architectures to meet challenging power, performance, mass, volume, reliability, and fault tolerance of future missions. The testbed facility has two levels of testbeds: (1) a Proof-of-Concept (POC) Testbed and (2) an Engineering Model Testbed. The methodology of the testbed development and the process of technology infusion are presented in a separate paper in this conference. This paper focuses only on the design, implementation, and application of the POC testbed. Additional information is contained in the original extended abstract.

Chau, S. N.↗
NASA NTRS2001

Advanced RF Front End Technology

The ability to achieve low-mass low-cost micro/nanospacecraft for Deep Space exploration requires extensive miniaturization of all subsystems. The front end of the Telecommunication subsystem is an area in which major mass (factor of 10) and volume (factor of 100) reduction can be achieved via the development of new silicon based micromachined technology and devices. Major components that make up the front end include single-pole and double-throw switches, diplexer, and solid state power amplifier. JPL's Center For Space Microsystems - System On A Chip (SOAC) Program has addressed the challenges of front end miniaturization (switches and diplexers). Our objectives were to develop the main components that comprise a communication front end and enable integration in a single module that we refer to as a 'cube'. In this paper we will provide the latest status of our Microelectromechanical System (MEMS) switches and surface micromachined filter development. Based on the significant progress achieved we can begin to provide guidelines of the proper system insertion for these emerging technologies. Additional information is contained in the original extended abstract.

Herman, M. I.↗
NASA NTRS2001

Ultra Low Power, Radiation Tolerant UHF Radio Technologies for In Situ Communication Applications

For future deep space missions, significant reductions in the mass and power requirements for short-range telecommunication systems will be critical in enabling a wide variety of new mission concepts. These possibilities include penetrators, gliders, miniature rovers, and sensor networks. Under joint funding from NASA's Cross Enterprise and JPL's Telecommunications and Mission technology programs, recent development activity has focused on the design of ultralow mass and power transceiver systems and subsystems suitable for operation in a flight environment. For these efforts, the functionality of the transceiver has been targeted towards a specific Mars communications scenario. However, the overall architecture is well suited to any short or medium range application where a remote probe will aperiodically communicate with a base station, possibly an orbiter, for the eventual purpose of relaying science information back to Earth. In 2001, these sponsors have been augmented with collaborative expertise and funding from JPL's Center for Integrated Space Microsystems in order to migrate existing concepts and designs to a System on a Chip (SOAC) solution. Additional information is contained in the original extended abstract.

Lay, N. E.↗
NASA NTRS2001

A Library of Rad Hard Mixed-Voltage/Mixed-Signal Building Blocks for Integration of Avionics Systems for Deep Space

To build the sensor intensive system-on-a-chip for the next generation spacecrafts for deep space, Center for Integration of Space Microsystems at JPL (CISM) takes advantage of the lower power rating and inherent radiation resistance of Silicon on Insulator technology (SOI). We are developing a suite of mixed-voltage and mixed-signal building blocks in Honeywell's SOI process that can enable the rapid integration of the next generation avionics systems with lower power rating, higher reliability, longer life, and enhanced radiation tolerance for spacecrafts such as the Europa Orbiter and Europa Lander. The mixed-voltage building blocks are predominantly for design of adaptive power management systems. Their design centers around an LDMOS structure that is being developed by Honeywell, Boeing Corp, and the University of Idaho. The mixed-signal building blocks are designed to meet the low power, extreme radiation requirement of deep space applications. These building blocks are predominantly used to interface analog sensors to the digital CPU of the next generation avionics system on a chip. Additional information is contained in the original extended abstract.

Mojarradi, M. M.↗
NASA NTRS2000

A Visual Editor in Java for View

In this project we continued the development of a visual editor in the Java programming language to create screens on which to display real-time data. The data comes from the numerous systems monitoring the operation of the space shuttle while on the ground and in space, and from the many tests of subsystems. The data can be displayed on any computer platform running a Java-enabled World Wide Web (WWW) browser and connected to the Internet. Previously a special-purpose program bad been written to display data on emulations of character-based display screens used for many years at NASA. The goal now is to display bit-mapped screens created by a visual editor. We report here on the visual editor that creates the display screens. This project continues the work we bad done previously. Previously we had followed the design of the 'beanbox,' a prototype visual editor created by Sun Microsystems. We abandoned this approach and implemented a prototype using a more direct approach. In addition, our prototype is based on newly released Java 2 graphical user interface (GUI) libraries. The result has been a visually more appealing appearance and a more robust application.

Stansifer, Ryan↗
NASA NTRS2000

An Open Source Web Map Server Implementation For California and the Digital Earth: Lessons Learned

This paper describes an Open Source implementation of the Open GIS Consortium's Web Map interface. It is based on the very popular Apache WWW Server, the Sun Microsystems Java ServIet Development Kit, and a C language shared library interface to a spatial datastore. This server was initially written as a proof of concept, to support a National Aeronautics and Space Administration (NASA) Digital Earth test bed demonstration. It will also find use in the California Land Science Information Partnership (CaLSIP), a joint program between NASA and the state of California. At least one WebMap enabled server will be installed in every one of the state's 58 counties. This server will form a basis for a simple, easily maintained installation for those entities that do not yet require one of the larger, more expensive, commercial offerings.

Sullivan, D. V.↗
NASA NTRS1998

An Implementation Plan for NFS at NASA's NAS Facility

This document discusses how NASA's NAS can benefit from the Sun Microsystems' Network File System (NFS). A case study is presented to demonstrate the effects of NFS on the NAS supercomputing environment. Potential problems are addressed and an implementation strategy is proposed.

Lam, Terance L.↗
NASA NTRS2002

Application of Reconfigurable Computing Technology to Multi-KiloHertz Micro-Laser Altimeter (MMLA) Data Processing

The Multi-KiloHertz Micro-Laser Altimeter (MMLA) is an aircraft based instrument developed by NASA Goddard Space Flight Center with several potential spaceflight applications. This presentation describes how reconfigurable computing technology was employed to perform MMLA signal extraction in real-time under realistic operating constraints. The MMLA is a "single-photon-counting" airborne laser altimeter that is used to measure land surface features such as topography and vegetation canopy height. This instrument has to date flown a number of times aboard the NASA P3 aircraft acquiring data at a number of sites in the Mid-Atlantic region. This instrument pulses a relatively low-powered laser at a very high rate (10 kHz) and then measures the time-of-flight of discrete returns from the target surface. The instrument then bins these measurements into a two-dimensional array (vertical height vs. horizontal ground track) and selects the most likely signal path through the array. Return data that does not correspond to the selected signal path are classified as noise returns and are then discarded. The MMLA signal extraction algorithm is very compute intensive in that a score must be computed for every possible path through the two dimensional array in order to select the most likely signal path. Given a typical array size with 50 x 6, up to 33 arrays must be processed per second. And for each of these arrays, roughly 12,000 individual paths must be scored. Furthermore, the number of paths increases exponentially with the horizontal size of the array, and linearly with the vertical size. Yet, increasing the horizontal and vertical sizes of the array offer science advantages such as improved range, resolution, and noise rejection. Due to the volume of return data and the compute intensive signal extraction algorithm, the existing PC-based MMLA data system has been unable to perform signal extraction in real-time unless the array is limited in size to one column, This limits the ability of the MMLA to operate in environments with sparse signal returns and a high number of noise return. However, under an IR&D project, an FPGA-based, reconfigurable computing data system has been developed that has been demonstrated to perform real-time signal extraction under realistic operating constraints. This reconfigurable data system is based on the commercially available Firebird Board from Annapolis Microsystems. This PCI board consists of a Xilinx Virtex 2000E FPGA along with 36 MB of SRAM arranged in five separately addressable banks. This board is housed in a rackmount PC with dual 850MHz Pentium processors running the Windows 2000 operating system. This data system performs all signal extraction in hardware on the Firebird, but also runs the existing "software based" signal extraction in tandem for comparison purposes. Using a relatively small amount of the Virtex XCV2000E resources, the reconfigurable data system has demonstrated to improve performance improvement over the existing software based data system by an order of magnitude. Performance could be further improved by employing parallelism. Ground testing and a preliminary engineering test flight aboard the NASA P3 has been performed, during which the reconfigurable data system has been demonstrated to match the results of the existing data system.

Powell, Wesley↗
NASA NTRS2002

System Model for MEMS based Laser Ultrasonic Receiver

A need has been identified for more advanced nondestructive Evaluation technologies for assuring the integrity of airframe structures, wiring, etc. Laser ultrasonic inspection instruments have been shown to detect flaws in structures. However, these instruments are generally too bulky to be used in the confined spaces that are typical of aerospace vehicles. Microsystems technology is one key to reducing the size of current instruments and enabling increased inspection coverage in areas that were previously inaccessible due to instrument size and weight. This paper investigates the system modeling of a Micro OptoElectroMechanical System (MOEMS) based laser ultrasonic receiver. The system model is constructed in software using MATLAB s dynamical simulator, Simulink. The optical components are modeled using geometrical matrix methods and include some image processing. The system model includes a test bench which simulates input stimuli and models the behavior of the material under test.

Wilson, William C.↗
NASA NTRS2003

Functional nanocomposites prepared by self-assembly and polymerization of diacetylene surfactants and silicic acid

Conjugated polymer/silica nanocomposites with hexagonal, cubic, or lamellar mesoscopic order were synthesized by self-assembly using polymerizable amphiphilic diacetylene molecules as both structure-directing agents and monomers. The self-assembly procedure is rapid and incorporates the organic monomers uniformly within a highly ordered, inorganic environment. By tailoring the size of the oligo(ethylene glycol) headgroup of the diacetylene-containing surfactant, we varied the resulting self-assembled mesophases of the composite material. The nanostructured inorganic host altered the diacetylene polymerization behavior, and the resulting nanocomposites show unique thermo-, mechano-, and solvatochromic properties. Polymerization of the incorporated surfactants resulted in polydiacetylene (PDA)/silica nanocomposites that were optically transparent and mechanically robust. Molecular modeling and quantum calculations and (13)C spin-lattice relaxation times (T(1)) of the PDA/silica nanocomposites indicated that the surfactant monomers can be uniformly organized into precise spatial arrangements prior to polymerization. Nanoindentation and gas transport experiments showed that these nanocomposite films have increased hardness and reduced permeability as compared to pure PDA. Our work demonstrates polymerizable surfactant/silica self-assembly to be an efficient, general approach to the formation of nanostructured conjugated polymers. The nanostructured inorganic framework serves to protect, stabilize, and orient the polymer, mediate its performance, and provide sufficient mechanical and chemical stability to enable integration of conjugated polymers into devices and microsystems.

NASA Discipline Life Support Systems↗
NASA NTRS2001

Self-assembly of mesoscopically ordered chromatic polydiacetylene/silica nanocomposites

Nature abounds with intricate composite architectures composed of hard and soft materials synergistically intertwined to provide both useful functionality and mechanical integrity. Recent synthetic efforts to mimic such natural designs have focused on nanocomposites, prepared mainly by slow procedures like monomer or polymer infiltration of inorganic nanostructures or sequential deposition. Here we report the self-assembly of conjugated polymer/silica nanocomposite films with hexagonal, cubic or lamellar mesoscopic order using polymerizable amphiphilic diacetylene molecules as both structure-directing agents and monomers. The self-assembly procedure is rapid and incorporates the organic monomers uniformly within a highly ordered, inorganic environment. Polymerization results in polydiacetylene/silica nanocomposites that are optically transparent and mechanically robust. Compared to ordered diacetylene-containing films prepared as Langmuir monolayers or by Langmuir-Blodgett deposition, the nanostructured inorganic host alters the diacetylene polymerization behaviour, and the resulting nanocomposite exhibits unusual chromatic changes in response to thermal, mechanical and chemical stimuli. The inorganic framework serves to protect, stabilize, and orient the polymer, and to mediate its function. The nanocomposite architecture also provides sufficient mechanical integrity to enable integration into devices and microsystems.

NASA Discipline Life Support Systems↗
NASA NTRS2005

Preparation and Analysis of Platinum Thin Films for High Temperature Sensor Applications

A study has been made of platinum thin films for application as high temperature resistive sensors. To support NASA Glenn Research Center s high temperature thin film sensor effort, a magnetron sputtering system was installed recently in the GRC Microsystems Fabrication Clean Room Facility. Several samples of platinum films were prepared using various system parameters to establish run conditions. These films were characterized with the intended application of being used as resistive sensing elements, either for temperature or strain measurement. The resistances of several patterned sensors were monitored to document the effect of changes in parameters of deposition and annealing. The parameters were optimized for uniformity and intrinsic strain. The evaporation of platinum via oxidation during annealing over 900 C was documented, and a model for the process developed. The film adhesion was explored on films annealed to 1000 C with various bondcoats on fused quartz and alumina. From this compiled data, a list of optimal parameters and characteristics determined for patterned platinum thin films is given.

Wrbanek, John D.↗
NASA NTRS1998

Real-Time Sensor Validation System Developed

Real-time sensor validation improves process monitoring and control system dependability by ensuring data integrity through automated detection of sensor data failures. The NASA Lewis Research Center, Expert Microsystems, and Intelligent Software Associates have developed an innovative sensor validation system that can automatically detect automated sensor failures in real-time for all types of mission-critical systems. This system consists of a sensor validation network development system and a real-time kernel. The network development system provides tools that enable systems engineers to automatically generate software that can be embedded within an application. The sensor validation methodology captured by these tools can be scaled to validate any number of sensors, and permits users to specify system sensitivity. The resulting software reliably detects all types of sensor data failures.

Zakrajsek, June F.↗