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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 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
NASA NTRS2008

NASA Ares I Crew Launch Vehicle Upper Stage Avionics and Software Overview

Building on the heritage of the Saturn and Space Shuttle Programs for the Design, Development, Test, and Evaluation (DDT and E) of avionics and software for NASA's Ares I Crew Launch Vehicle (CLV), the Ares I Upper Stage Element is a vital part of the Constellation Program's transportation system. The Upper Stage Element's Avionics Subsystem is actively proceeding toward its objective of delivering a flight-certified Upper Stage Avionics System for the Ares I CLV.

Nola, Charles L.↗
NASA NTRS2003

Recovery of the Space Shuttle Columbia Avionics

Lessons Learned: a) Avionics data can playa critical role in the investigation of a "close call" or accident. b) Avionics designers should think about the role their systems might play in an investigation. c) Know your data, down to the bit level. d) Know your spacecraft - follow the data. e) Internal placement of circuit cards can affect their survivability. f) Think about how to reconstruct nonvolatile memory (e.g. serialize IC's, etc.) g) Use of external assets can aid in extracting data from avionics.

Hames, Kevin L.↗
NASA NTRS2011

NEXUS Scalable and Distributed Next-Generation Avionics Bus for Space Missions

A paper discusses NEXUS, a common, next-generation avionics interconnect that is transparently compatible with wired, fiber-optic, and RF physical layers; provides a flexible, scalable, packet switched topology; is fault-tolerant with sub-microsecond detection/recovery latency; has scalable bandwidth from 1 Kbps to 10 Gbps; has guaranteed real-time determinism with sub-microsecond latency/jitter; has built-in testability; features low power consumption (< 100 mW per Gbps); is lightweight with about a 5,000-logic-gate footprint; and is implemented in a small Bus Interface Unit (BIU) with reconfigurable back-end providing interface to legacy subsystems. NEXUS enhances a commercial interconnect standard, Serial RapidIO, to meet avionics interconnect requirements without breaking the standard. This unified interconnect technology can be used to meet performance, power, size, and reliability requirements of all ranges of equipment, sensors, and actuators at chip-to-chip, board-to-board, or box-to-box boundary. Early results from in-house modeling activity of Serial RapidIO using VisualSim indicate that the use of a switched, high-performance avionics network will provide a quantum leap in spacecraft onboard science and autonomy capability for science and exploration missions.

He, Yutao↗
NASA NTRS2011

GPM Avionics Module Heat Pipes Design and Performance Test Results

The Global Precipitation Measurement (GPM) mission is an international network of satellites that provide the next-generation global observations of rain and snow. The GPM core satellite carries an advanced radar / radiometer system to measure precipitation from space and serve as a reference standard to unify precipitation measurements from a constellation of research and operational satellites. Through improved measurements of precipitation globally, the GPM mission will help to advance our understanding of Earth's water and energy cycle, improve forecasting of extreme events that cause natural hazards and disasters, and extend current capabilities in using accurate and timely information of precipitation to directly benefit society. The avionics module on the core satellite contains a number of electronics boxes which are cooled by a network of aluminum/ammonia heat pipes and a honeycomb radiator which contains thirteen embedded aluminum/ammonia heat pipes. All heat pipes were individually tested by the vendor (Advanced Cooling Technologies, Inc.) prior to delivery. Following delivery to NASA, the flight avionics radiator and the flight spare transport heat pipes were mounted to flight-like test structure and a system level thermal vacuum test was performed. This test, which used simulators in place of all electronics boxes, was done to verify the operation of the thermal control system as a whole. This presentation will discuss the design of the avionics module heat pipes, and then discuss performance tests results for the individual heat pipes prior to delivery and for the system level thermal vacuum test. All heat pipes met their performance requirements. However, it was found that the power was too low in some instances to start all of the smaller radiator spreader heat pipes when they were tested in a reflux configuration (which is the nominal test configuration). Although this lowered the efficiency of the radiator somewhat, it did not impact the operating temperatures of the electronics boxes.

Ottenstein, Laura↗
NASA NTRS2014

Investigation of HZETRN 2010 as a Tool for Single Event Effect Qualification of Avionics Systems

NASA's future missions are focused on long-duration deep space missions for human exploration which offers no options for a quick emergency return to Earth. The combination of long mission duration with no quick emergency return option leads to unprecedented spacecraft system safety and reliability requirements. It is important that spacecraft avionics systems for human deep space missions are not susceptible to Single Event Effect (SEE) failures caused by space radiation (primarily the continuous galactic cosmic ray background and the occasional solar particle event) interactions with electronic components and systems. SEE effects are typically managed during the design, development, and test (DD&T) phase of spacecraft development by using heritage hardware (if possible) and through extensive component level testing, followed by system level failure analysis tasks that are both time consuming and costly. The ultimate product of the SEE DD&T program is a prediction of spacecraft avionics reliability in the flight environment produced using various nuclear reaction and transport codes in combination with the component and subsystem level radiation test data. Previous work by Koontz, et al.1 utilized FLUKA, a Monte Carlo nuclear reaction and transport code, to calculate SEE and single event upset (SEU) rates. This code was then validated against in-flight data for a variety of spacecraft and space flight environments. However, FLUKA has a long run-time (on the order of days). CREME962, an easy to use deterministic code offering short run times, was also compared with FLUKA predictions and in-flight data. CREME96, though fast and easy to use, has not been updated in several years and underestimates secondary particle shower effects in spacecraft structural shielding mass. Thus, this paper will investigate the use of HZETRN 20103, a fast and easy to use deterministic transport code, similar to CREME96, that was developed at NASA Langley Research Center primarily for flight crew ionizing radiation dose assessments. HZETRN 2010 includes updates to address secondary particle shower effects more accurately, and might be used as another tool to verify spacecraft avionics system reliability in space flight SEE environments.

Rojdev, Kristina↗
NASA NTRS2019

Thermal, Avionics, and Power Considerations for Designing a Nuclear Thermal Propulsion Flight Demonstrator

As part of the Appropriations Bill passed by the US Congress in February 2019, NASA was instructed to develop a nuclear thermal propulsion (NTP) flight demonstrator by 2024. [4] In response to this directive, the Advanced Concepts Office (ACO) at Marshall Space Flight Center (MSFC) was tasked with beginning concept studies for the flight demonstration (FD) mission. During the NTP study formulation, two philoso- phies emerged with regards to FD concept design. The first, Flight Demo 1 (FD1), strictly observes the 2024 schedule requirement at the expense of lower engine performance than expected of theoretical NTP engines. The second concept, Flight Demo 2 (FD2), relaxes the schedule requirement to allow for higher engine performance and more traceability to future operational systems. Both the FD1 and FD2 concepts present considerable challenges for subsystem design, specifically in the areas of thermal control, avionics, and power. To guard against undesired graveyard orbits, a requirement to keep the NTP engine and the reaction control system (RCS) separate was put in place. As a result of this requirement, the avionics subsystem must provide separate command and data handling (CDH) and instrumentation for each propulsion system. In-space instrumentation and monitoring of a NTP system has never been done before, necessitating the development of novel strategies and unique hardware. The heating rates produced by the NTP engine are extremely high, leading to difficulties with thermal control. The FD1 concept utilizes high-pressure gaseous hydrogen (GH2), which is largely insensitive to temperature fluctuations. The FD2 concept, however, utilizes cryogenic liquid hydrogen (LH2) which must be kept stable near 20 Kelvin. A high-performance thermal control system (TCS) will be required to ensure all components and subsystems are maintained within their operational temperature ranges. This paper will highlight the thermal, avionics, and power solutions required for the full scope of challenges for a NTP flight demonstrator.

Johnson, W. E.↗
NASA NTRS2018

The International Space Station Space Radiation Environment: Avionics Systems Performance in Low-Earth Orbit Single Event Effects (SEE) Environments

Single event effects (SEE) are those errors, anomalies, or failures in microelectronic devices caused by the passage of a single energetic charged particle through the device. Spacecraft SEE environments consist primarily of energetic charged particles; both primary particles originating in the natural environment and secondary particles (including secondary neutrons) produced by nuclear reactions of primary particles with spacecraft materials. The energetic charged particle components (electrons, protons, and atomic nuclei) of the spacecraft SEE environment include galactic cosmic rays (GCR), and planetary radiation belt charged particles, as well as solar energetic particle event (SPE) charged particles. The International Space Station (ISS) orbital altitude and inclination (~350 km to ~420 km at 51.6o inclination) results in a spacecraft SEE environment that varies dramatically with the location in Earth?s geomagnetic field. Geomagnetic GCR shielding diminishes with distance from the geomagnetic equator. Near + 51.6o latitude the ISS GCR environment has a high degree of similarity to the interplanetary GCR environment in cis-Lunar space.SEE environments supporting ISS avionics systems design, development, test, and verification are documented in SSP-30512, Space Station Ionizing Radiation Design Environment. Comparisons of overall ISS avionics systems in-flight performance with pre-flight verification report predictions have been previously reported and meet or exceed expectations in all cases.In this paper we report the results of more detailed investigations of the effects of geographic location, altitude, solar cycle, and shielding mass effects on the in-flight SEE performance of the ISS command and data handling system during the past 17 years. In addition, we report on the preflight testing and in-flight performance of the commercial-off-the-shelf lap top computers used on ISS. Finally, we present an assessment of ISS as an avionics SEE test and flight demonstration platform for exploration hardware destined for the cis-lunar or other inner solar system environments.

International Space Station↗
NASA NTRS2018

Compact Low Power Avionics for the Europa Lander Concept and Other Missions to Ocean Worlds

This paper presents the results of NASA’s Game Changing Technology development entitled “Ultra Low Temperature Electronics” and ColdTech technology effort entitled “Cold Survivable Distributed Motor Controller”. The purpose of these back-to-back projects is to address the Command & Data Handling (CDH), Power and Motor Control needs for missions to ocean worlds such as the potential Europa Lander project. We addressed the mass reduction challenge by developing the key technologies necessary to design a next generation compact motor control avionics. The project’s goal is to allow a Europa Lander to last longer on the surface and provide more room for additional science by reducing the volume, mass and power of its avionics and the amount of energy required to keep the avionics warm.

Suh, Jong-ook↗
NASA NTRSDate not supplied

An Overview of the Current State of the Art on Small Spacecraft Avionics Architectures

This paper will expand on the technological progression of small spacecraft avionicsystems and architectures. The authors will identify modern requirements of avionics systems to meet the need of the modern, complex small spacecraft, expand upon the updated avionics architecture composition, list any challenges this technology may encounter, and highlight activities that are being conducted to develop a new generational small spacecraft avionics system.

Bruce Daniel Yost↗
NASA NTRS2022

Europa Clipper Payload Verification and Validation: Avionics-Instrument Interface Test Campaign

NASA's Europa Clipper mission will investigate Jupiter's icy moon Europa using a payload suite consisting of nine instruments to address a range of scientific objectives concerning Europa's habitability. As the project proceeds past its Critical Design Review, confidence is being built in the system's ability to achieve mission objectives through the implementation of a rigorous payload verification and validation (V&V) program. As part of this payload V&V program, instrument box-level testing was performed by the payload team to verify select instrument-avionics interface requirements. This testing was performed at JPL using the avionics testbed's Bulk Data Storage Emulator (BDSEM) with visiting instrument Test Models. This paper summarizes the Data Link test campaign involving roughly four days of functional testing per instrument, including planning, testing methods, types of issues found, and the requirement closure process. Detail is also provided on the development, deployment, and validation of a standardized analysis tool used in data reviews. This testing verified requirements related to commanding rates, loss of link, packet format, clock counters, loopback test capability, and SpaceWire jitter and skew margins. Additional risk reduction testing of basic commanding, counter behavior, science data collection and transfer, and interface swapping was also performed. Because the BDSEM venue was not originally designed to be a run for record venue, the process of characterizing venue fidelity and establishing suitability for requirement closure using data collected in this venue will also be addressed.In order to close requirements, an extensible tool was developed to post-process instrument command and telemetry data from their original binary to a human-readable format and give visibility to errors detected within the data, such as packets with Cyclic Redundancy Check errors. This tool, called payload-packet-parser, is a Python 3.9 command line tool built using a variety of open-source Python libraries. Payload-packet-parser was designed to support parsing command and telemetry packets for all Europa Clipper instruments and additional analysis tools were developed for verification of specific information interface requirements. This test campaign, including post-processing using a single parsing and verification toolset, allowed for early interface testing, alleviating testing burdens on instrument teams and buying down risk on the instrument-avionics interface by finding hardware and software issues and idiosyncrasies prior to integration with system test venues. Over twenty issues were discovered across the payload, resulting in software updates and instrument rework well in advance of any system impacts. This paper concludes with an assessment of benefits and costs of this type of testing and lessons learned.

Montanez, Leticia↗
NASA NTRS2014

Developing Avionics Hardware and Software for Rocket Engine Testing

My summer was spent working as an intern at Kennedy Space Center in the Propulsion Avionics Branch of the NASA Engineering Directorate Avionics Division. The work that I was involved with was part of Rocket University's Project Neo, a small scale liquid rocket engine test bed. I began by learning about the layout of Neo in order to more fully understand what was required of me. I then developed software in LabView to gather and scale data from two flowmeters and integrated that code into the main control software. Next, I developed more LabView code to control an igniter circuit and integrated that into the main software, as well. Throughout the internship, I performed work that mechanics and technicians would do in order to maintain and assemble the engine.

liquid rocket↗
NASA NTRS2015

Affordable Vehicle Avionics Overview

Public and private launch vehicle developers are reducing the cost of propulsion for small commercial launchers, but conventional high-performance, high-reliability avionics remain the disproportionately high cost driver for launch. AVA technology performs as well or better than conventional launch vehicle avionics, but with a fraction of the recurring costs. AVA enables small launch providers to offer affordable rides to LEO to nano-satellites as primary payloads meaning, small payloads can afford to specify their own launch and orbit parameters

avionics↗
NASA NTRS2024

Failure-Tolerant Avionics for Crewed Space Systems Recommended Best Practices

This paper provides an overview of some of the major steps needed to mature and justify the design of an avionics system for crewed spacecraft. It is organized as a collection of artifacts or pieces of evidence that NASA needs to assess the system at design reviews, including a functional failure modes and effects analysis (FFMEA), fault containment region (FCR) definitions, the failure hypothesis, and reliability analysis. This paper is intended as a reference for designers working on NASA crewed spaceflight projects, reliability engineers responsible for avionics system assessments, and program managers wanting to understand what evidence is required at design reviews to ensure crew safety and mission success.

Avionics↗
NASA NTRS2024

Key Considerations When Developing Avionics for Safety-Critical Systems

Multiple human spaceflight programs are underway at NASA including Orion, Space Launch System, Gateway, Human Landing System, and EVA and Lunar Surface Mobility programs. Achieving success in these programs requires NASA to collaborate with a variety of commercial partners, including both new spaceflight companies and robotic spaceflight companies pursuing crewed spaceflight for the first time. It is not always clear to these organizations how to show their systems are safe for human spaceflight. This is particularly true for avionics systems, which are responsible for performing some of a crewed spacecraft’s most critical functions. NASA recently published guidance describing how to show the design of an avionic system meets safety requirements for crewed missions.

Safety-Critical Systems↗
NASA NTRS1971

Telemetry and the integrated avionics approach.

The unique problems encountered in the integrated approach to aircraft and spacecraft avionics system designs are discussed with the emphasis on recent advances in telemetry as a factor facilitating the integration. A listing of subsystems planned for integration on the Space Shuttle vehicle is given, covering auxiliary pumping and propellant, crew controls and displays, computation, communications and radar, electric power, guidance, navigation and control, air-bearing engines, main engines, reaction control, and structural/mechanical elements. Considerations are given for the multiplexed data bus design applicable to integrated avionics.

Frost, W. O.↗
NASA NTRS1971

ACS avionics systems review

Items covered in this study include: (1) refining the baseline avionics system design; (2) clarification of key issues for RFP; and (3) refining the baseline avionics system costs.

Source record↗
NASA NTRS1975

Space Tug avionics definition study. Volume 1: Executive summary

A top down approach was used to identify, compile, and develop avionics functional requirements for all flight and ground operational phases. Such requirements as safety mission critical functions and criteria, minimum redundancy levels, software memory sizing, power for tug and payload, data transfer between payload, tug, shuttle, and ground were established. Those functional requirements that related to avionics support of a particular function were compiled together under that support function heading. This unique approach provided both organizational efficiency and traceability back to the applicable operational phase and event. Each functional requirement was then allocated to the appropriate subsystems and its particular characteristics were quantified.

Source record↗