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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 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
NASA NTRS2003

Electrical Devices and Circuits for Low Temperature Space Applications

The environmental temperature in many NASA missions, such as deep space probes and outer planetary exploration, is significantly below the range for which conventional commercial-off-the-shelf electronics is designed. Presently, spacecraft operating in the cold environment of such deep space missions carry a large number of radioisotope or other heating units in order to maintain the surrounding temperature of the on-board electronics at approximately 20 C. Electronic devices and circuits capable of operation at cryogenic temperatures will not only tolerate the harsh environment of deep space but also will reduce system size and weight by eliminating or reducing the heating units and their associate structures; thereby reducing system development cost as well as launch costs. In addition, power electronic circuits designed for operation at low temperatures are expected to result in more efficient systems than those at room temperature. This improvement results from better behavior in the electrical and thermal properties of some semiconductor and dielectric materials at low temperatures. An on-going research and development program on low temperature electronics at the NASA Glenn Research Center focuses on the development of efficient electrical systems and circuits capable of surviving and exploiting the advantages of low temperature environments. An overview of the program will be presented in this paper. A description of the low temperature test facilities along with selected data obtained from in-house component testing will also be discussed. On-going research activities that are being performed in collaboration with various organizations will also be presented.

Patterson, R. L.↗
DOE OSTI2025

A Class of Sparse Johnson–Lindenstrauss Transforms and Analysis of their Extreme Singular Values

The Johnson–Lindenstrauss (JL) lemma is a powerful tool for dimensionality reduction in modern algorithm design. The lemma states that any set of high-dimensional points in a Euclidean space can be projected into lower dimensions while approximately preserving pairwise Euclidean distances. Random matrices satisfying this lemma are called JL transforms (JLTs). Inspired by existing $s$-hashing JLTs with exactly $s$ nonzero elements on each column, the present work introduces an ensemble of sparse matrices encompassing so-called $s$-hashing-like matrices whose expected number of nonzero elements on each column is $s$. The independence of the sub-Gaussian entries of these matrices and the knowledge of their exact distribution play an important role in their analyses. Using properties of independent sub-Gaussian random variables, these matrices are demonstrated to be JLTs, and their smallest nontrivial singular values and largest singular values are estimated nonasymptotically using a technique from geometric functional analysis. As the dimensions of the matrix grow to infinity, these singular values are proved to converge almost surely to fixed quantities (by using the universal Bai–Yin law) and in distribution to the Gaussian orthogonal ensemble Tracy–Widom law after proper rescalings. Understanding the behaviors of extreme singular values is important in general because they are often used to define a measure of stability of matrix algorithms. For example, JLTs were recently used in derivative-free optimization algorithmic frameworks to select random subspaces in which are constructed random models or poll directions to achieve scalability, and hence estimating their smallest singular value in particular helps determine the dimension of these subspaces.

97 MATHEMATICS AND COMPUTING↗
NASA NTRS1978

Space Shuttle Program description and status

The main reason for the development of the Space Shuttle is related to the aim to achieve a major reduction in the cost of placing a payload into space. Such a reduction is to be obtained by using a reusable in place of an expendable launch vehicle. Developments concerning launch vehicles show a steady reduction in launching expenses. From a cost of about $500,000 a pound in the late 1950's, launching expenses were reduced to $600 a pound for payloads on the Saturn V. With the Space Shuttle the cost will drop to approximately $150 a pound. The Space Shuttle Program is discussed, taking into account a system description, a typical mission profile, aspects of mission design, launch costs, and Space Shuttle characteristics. The Space Shuttle Program status is also examined, giving attention to orbital flight schedules, flight hardware tests, launch area facilities, the mission control center, and details of flight crew training.

Macleod, J. B.↗
NASA NTRS1980

The development of a Space Shuttle Research Animal Holding Facility

The ability to maintain the well being of experiment animals is of primary importance to the successful attainment of life sciences flight experiment goals. To assist scientists in the conduct of life sciences flight experiments, a highly versatile Research Animal Holding Facility (RAHF) is being developed for use on Space Shuttle/Spacelab missions. This paper describes the design of the RAHF system, which in addition to providing general housing for various animal species, approximating the environment found in ground based facilities, is designed to minimize disturbances of the specimens by vehicle and mission operations. Life-sustaining capabilities such as metabolic support and environmental control are provided. RAHF is reusable and is a modular concept to accommodate animals of different sizes. The basic RAHF system will accommodate a combination of 24 500-g rats or 144 mice or a mixed number of rats and mice. An alternative design accommodates four squirrel monkeys. The entire RAHF system is housed in a single ESA rack. The animal cages are in drawers which are removable for easy access to the animals. Each cage contains a waste management system, a feeding system and a watering system all of which will operate in zero or one gravity.

Jagow, R. B.↗
NASA NTRS2010

Space Station Control Moment Gyroscope Lessons Learned

Four 4760 Nms (3510 ft-lbf-s) Double Gimbal Control Moment Gyroscopes (DGCMG) with unlimited gimbal freedom about each axis were adopted by the International Space Station (ISS) Program as the non-propulsive solution for continuous attitude control. These CMGs with a life expectancy of approximately 10 years contain a flywheel spinning at 691 rad/s (6600 rpm) and can produce an output torque of 258 Nm (190 ft-lbf)1. One CMG unexpectedly failed after approximately 1.3 years and one developed anomalous behavior after approximately six years. Both units were returned to earth for failure investigation. This paper describes the Space Station Double Gimbal Control Moment Gyroscope design, on-orbit telemetry signatures and a summary of the results of both failure investigations. The lessons learned from these combined sources have lead to improvements in the design that will provide CMGs with greater reliability to assure the success of the Space Station. These lessons learned and design improvements are not only applicable to CMGs but can be applied to spacecraft mechanisms in general.

Gurrisi, Charles↗
NASA NTRS1989

Project Argo: The design and analysis of an all-propulsive and an aeroassisted version of a manned space transportation vehicle

Project Argo is the design of a manned Space Transportation Vehicle (STV) that would transport payloads between LEO (altitude lying between 278 to 500 km above the Earth) and GEO (altitude is approximately 35,800 km above the Earth) and would be refueled and refurbished at the Space Station Freedom. Argo would be man's first space-based manned vehicle and would provide a crucial link to geosynchronous orbit where the vast majority of satellites are located. The vehicle could be built and launched shortly after the space station and give invaluable space experience while serving as a workhorse to deliver and repair satellites. Eventually, if a manned space station is established in GEO, then Argo could serve as the transport between the Space Station Freedom and a Geostation. If necessary, modifications could be made to allow the vehicle to reach the moon or possibly Mars. Project Argo is unique in that it consists of the design and comparison of two different concepts to accomplish the same mission. The first is an all-propulsive vehicle which uses chemical propulsion for all of its major maneuvers between LEO and GEO. The second is a vehicle that uses aeroassisted braking during its return from GEO to LEO by passing through the upper portions of the atmosphere.

Source record↗
NASA NTRS2018

Telescope Design for LISA

The Laser Interferometer Space Antenna (LISA) Mission Proposal was selected in June 2017 for the L3 opportunity as part of ESA's Cosmic Visions Program. A space-based gravitational wave observatory requires optical telescopes to enable displacement measurements between pairs of drag-free proof masses with a precision of approximately 10 picometers/Hz over separations of 2.5 million km. We describe the somewhat unusual requirements for these telescopes and a proposed design that would meet these requirements.

Livas, Jeffrey C.↗
NASA NTRS1990

The design-to-cost manifold

A mathematical technique which both quantifies the design-to-cost process and the mass/complexity issue is presented. A simplified approximation of the PRICE H production-production cost is used to generate a dual set of differential equations which define the directions of maximum and minimum cost change over (mass, complexity) space. The equations are solved in closed form to obtain the one-dimensional design-to-cost and design-for-cost spaces. Preliminary results indicate that cost is relatively insensitive to changes in mass and that the reduction of complexity, both in the manufacturing process and in the spacecraft itself, is dominant in reducing cost. Two major objections to the design-to-cost method are discussed.

Dean, Edwin B.↗
NASA NTRS2005

Avionics for a Small Robotic Inspection Spacecraft

A report describes the tentative design of the avionics of the Mini-AERCam -- a proposed 7.5-in. (approximately 19-cm)-diameter spacecraft that would contain three digital video cameras to be used in visual inspection of the exterior of a larger spacecraft (a space shuttle or the International Space Station). The Mini-AERCam would maneuver by use of its own miniature thrusters under radio control by astronauts inside the larger spacecraft. The design of the Mini-AERCam avionics is subject to a number of constraints, most of which can be summarized as severely competing requirements to maximize radiation hardness and maneuvering, image-acquisition, and data-communication capabilities while minimizing cost, size, and power consumption. The report discusses the design constraints, the engineering approach to satisfying the constraints, and the resulting iterations of the design. The report places special emphasis on the design of a flight computer that would (1) acquire position and orientation data from a Global Positioning System receiver and a microelectromechanical gyroscope, respectively; (2) perform all flight-control (including thruster-control) computations in real time; and (3) control video, tracking, power, and illumination systems.

Abbott, Larry↗
NASA NTRS1991

Conceptual design of two-stage-to-orbit hybrid launch vehicle

The object of this design class was to design an earth-to orbit vehicle to replace the present NASA space shuttle. The major motivations for designing a new vehicle were to reduce the cost of putting payloads into orbit and to design a vehicle that could better service the space station with a faster turn-around time. Another factor considered in the design was that near-term technology was to be used. Materials, engines and other important technologies were to be realized in the next 10 to 15 years. The first concept put forth by NASA to meet these objectives was the National Aerospace Plane (NASP). The NASP is a single-stage earth-to-orbit air-breathing vehicle. This concept ran into problems with the air-breathing engine providing enough thrust in the upper atmosphere, among other things. The solution of this design class is a two-stage-to-orbit vehicle. The first stage is air-breathing and the second stage is rocket-powered, similar to the space shuttle. The second stage is mounted on the top of the first stage in a piggy-back style. The vehicle takes off horizontally using only air-breathing engines, flies to Mach six at 100,000 feet, and launches the second stage towards its orbital path. The first stage, or booster, will weigh approximately 800,000 pounds and the second stage, or orbiter will weigh approximately 300,000 pounds. The major advantage of this design is the full recoverability of the first stage compared with the present solid rocket booster that are only partially recoverable and used only a few times. This reduces the cost as well as providing a more reliable and more readily available design for servicing the space station. The booster can fly an orbiter up, turn around, land, refuel, and be ready to launch another orbiter in a matter of hours.

Source record↗
NASA NTRS1974

The Deep Space Network

The objectives, functions, and organization, of the Deep Space Network are summarized. Deep Space stations, ground communications, and network operations control capabilities are described. The network is designed for two-way communications with unmanned spacecraft traveling approximately 1600 km from earth to the farthest planets in the solar system. It has provided tracking and data acquisition support for the following projects: Ranger, Surveyor, Mariner, Pioneer, Apollo, Helios, Viking, and the Lunar Orbiter.

Source record↗
NASA NTRS1978

Network functions and facilities

The objectives, functions, and organization of the Deep Space Network are summarized; deep space station, ground communication, and network operations control capabilities are described. The network is designed for two-way communications with unmanned spacecraft traveling approximately 16,000 km (10,000 miles) from earth to the farthest planets and to the edge of our solar system.

Renzetti, N. A.↗
NASA NTRS1980

Solar heating and hot water system installed at Shoney's Restaurant, North Little Rock, Arkansas

A solar heating system designed to supply a major portion of the space and water heating requirements for a restaurant is described. The restaurant has a floor space of approximately 4,650 square feet and requires approximate 1500 gallons of hot water daily. The solar energy system consists of 1,428 square feet of Chamberlain flat plate liquid collector subsystem, and a 1500 gallon storage subsystem circulating hot water producing 321 x 10 to the 6th power Btu/Yr (specified) building heating and hot water heating.

Source record↗
NASA NTRS1985

Sensor/Actuator Selection for the Constrained Variance Control Problem

The problem of designing a linear controller for systems subject to inequality variance constraints is considered. A quadratic penalty function approach is used to yield a linear controller. Both the weights in the quadratic penalty function and the locations of sensors and actuators are selected by successive approximations to obtain an optimal design which satisfies the input/output variance constraints. The method is applied to NASA's 64 meter Hoop-Column Space Antenna for satellite communications. In addition the solution for the control law, the main feature of these results is the systematic determination of actuator design requirements which allow the given input/output performance constraints to be satisfied.

Delorenzo, M. L.↗
NASA NTRS1997

The Gamma-ray Large Area Space Telescope (GLAST) Mission Concept Study

The Gamma-ray Large Area Space Telescope (GLAST), a next generation high-energy gamma-ray mission designed to observe cosmic sources of gamma-rays over the approximate energy range from 10 MeV to 300 GeV, was studied for possible flight in the next decade. The GLAST baseline mission studied will achieve a major advance in sensitivity beyond EGRET by the use of modern particle physics tracking technology. The baseline instrument design that has been extensively studied uses solid-state silicon strip detectors for particle tracking and efficient on-board data processing and event triggering to achieve more than an order of magnitude improvement in sensitivity compared to EGRET. Development of technology requirements and a technology development roadmap for the GLAST mission is presented.

Michelson, Peter F.↗
NASA NTRS2014

Asteroid Redirect Robotic Mission: Robotic Boulder Capture Option Overview

The National Aeronautics and Space Administration (NASA) is currently studying an option for the Asteroid Redirect Robotic Mission (ARRM) that would capture a multi-ton boulder (typically 2-4 meters in size) from the surface of a large (is approximately 100+ meter) Near-Earth Asteroid (NEA) and return it to cislunar space for subsequent human and robotic exploration. This alternative mission approach, designated the Robotic Boulder Capture Option (Option B), has been investigated to determine the mission feasibility and identify potential differences from the initial ARRM concept of capturing an entire small NEA (4-10 meters in size), which has been designated the Small Asteroid Capture Option (Option A). Compared to the initial ARRM concept, Option B allows for centimeter-level characterization over an entire large NEA, the certainty of target NEA composition type, the ability to select the boulder that is captured, numerous opportunities for mission enhancements to support science objectives, additional experience operating at a low-gravity planetary body including extended surface contact, and the ability to demonstrate future planetary defense strategies on a hazardous-size NEA. Option B can leverage precursor missions and existing Agency capabilities to help ensure mission success by targeting wellcharacterized asteroids and can accommodate uncertain programmatic schedules by tailoring the return mass.

Mazanek, Daniel D.↗
NASA NTRS2019

Rapid Development of the Seeker Free-Flying Inspector Guidance, Navigation, and Control System

Seeker is an automated extravehicular free-flying inspector CubeSat designed and built in-house at the Johnson Space Center (JSC). As a Class 1E project funded by the International Space Station (ISS) Program, Seeker had a streamlined process to flight certification, but the vehicle had to be designed, developed, tested, and delivered within approximately one year after authority to pro-ceed (ATP) and within a $1.8 million budget. These constraints necessitated an expedited Guidance, Navigation, and Control (GNC) development schedule, development began with a navigation sensor trade study using Linear Covariance (LinCov) analysis and a rapid sensor downselection process, resulting in the use of commercial off-the-shelf (COTS) sensors which could be procured quickly and subjected to in-house environmental testing to qualify them for flight. A neural network was used to enable a COTS camera to provide bearing measurements for visual navigation. The GNC flight software (FSW) algorithms utilized lean development practices and leveraged the Core Flight Software (CFS) architecture to rapidly develop the GNC system, tune the system parameters, and verify performance in simulation. This pace was anchored by several Hardware-Software Integration (HSI) milestones, which forced the Seeker GNC team to develop the interfaces both between hardware and software and between the GNC domains early in the project and to enable a timely delivery.

Sullivan, Jacob↗
NASA NTRS1980

Design requirements for high-efficiency high concentration ratio space solar cells

A miniaturized Cassegrainian concentrator system concept was developed for low cost, multikilowatt space solar arrays. The system imposes some requirements on solar cells which are new and different from those imposed for conventional applications. The solar cells require a circular active area of approximately 4 mm in diameter. High reliability contacts are required on both front and back surfaces. The back area must be metallurgically bonded to a heat sink. The cell should be designed to achieve the highest practical efficiency at 100 AMO suns and at 80 C. The cell design must minimize losses due to nonuniform illumination intensity and nonnormal light incidence. The primary radiation concern is the omnidirectional proton environment.

Rauschenbach, H.↗