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All sourcesNASA NTRSDOE OSTI
NASA NTRS2007

Advanced Image Processing for NASA Applications

The future of space exploration will involve cooperating fleets of spacecraft or sensor webs geared towards coordinated and optimal observation of Earth Science phenomena. The main advantage of such systems is to utilize multiple viewing angles as well as multiple spatial and spectral resolutions of sensors carried on multiple spacecraft but acting collaboratively as a single system. Within this framework, our research focuses on all areas related to sensing in collaborative environments, which means systems utilizing intracommunicating spatially distributed sensor pods or crafts being deployed to monitor or explore different environments. This talk will describe the general concept of sensing in collaborative environments, will give a brief overview of several technologies developed at NASA Goddard Space Flight Center in this area, and then will concentrate on specific image processing research related to that domain, specifically image registration and image fusion.

LeMoign, Jacqueline↗
NASA NTRS1991

Utilizing expert systems for satellite monitoring and control

Spacecraft analysts in the spacecraft control center for the Cosmic Background Explorer (COBE) satellite are currently utilizing a fault-isolation expert system developed to assist in the isolation and correction of faults in the communications link. This system, the communication link expert assistance resource (CLEAR), monitors real time spacecraft and ground systems performance parameters in search of configuration discrepancies and communications link problems. If such a discrepancy or problem is isolated, CLEAR alerts the analyst and provides advice on how to resolve the problem swiftly and effectively. The CLEAR system is the first real time expert system to be used in the operational environment of a satellite control center at the NASA Goddard Space Flight Center. Clear has not only demonstrated the utility and potential of an expert system in the demanding environment of a satellite control center, but also has revealed many of the pitfalls and deficiencies of development of expert systems. One of the lessons learned from this and other initial expert system projects is that prototypes can often be developed quite rapidly, but operational expert systems require considerable effort. Development is generally a slow, tedious process that typically requires the special skills of trained programmers. Due to the success of CLEAR and several other systems in the control center domain, a large number of expert systems will certainly be developed to support control center operations during the early 1990's. To facilitate the development of these systems, a project was initiated to develop an integrated, domain-specific tool, the generic spacecraft analyst assistent (GenSAA), that alows the spacecraft analysts to rapidly create simple expert systems themselves. By providing a highly graphical point-and-select method of system development, GenSAA allows the analyst to utilize and/or modify previously developed rule bases and system components; thus, facilitating software reuse and reducing development time and effort.

Hughes, Peter M.↗
NASA NTRSDate not supplied

The Cosmic Radiation Symphony: Soundtrack for a Journey to Mars

Space radiation (SR) is a constant threat to astronauts who journey away from the Earth’s protective magnetosphere. Galactic cosmic rays (GCR) are atomic nuclei from remnants of supernovae and are omnipresent in outer space. These ionized particles travel close to the speed of light and when they traverse biological material,they leave behind a path of damage. Another space radiation threat is from our sun when solar particle events (SPEs), or bursts of energetic protons,occur. Exposure to space radiation can lead to cancer, cardiovascular disease,immune dysfunction, and cognitive and behavioral decrements. Yet humans cannot see, smell, taste, hear,or feel radiation, making it less tangible than other health threats and much more difficult to describe.This is an important gap in risk communication that the Space Radiation Element is working to close within NASA’s Human Research Program. Music and art are powerful means of communicating human emotions and feelings and are effective and creative ways to convey other types of information. In this work, the sonification process was used to transcribe or translate the physical nature of the SR environment on a 3-year mission to Mars into sound, a format perceptible to the human ear. A visual representation for the journey was also developed so the audience can both hear and envision the chronic presence of GCR and the acute and large bursts of energy present in SPEs. Data for this project were derived from the Radiation Assessment Detector on the NASA Curiosity Rover during its outbound cruise to Mars and on the Martian surface, as well as from models of the space radiation environment behind spacecraft shielding. Our data-driven audiovisual composition was realized using custom programmed digital signal processing and graphic design in the programming languages Pure Data and Processing. The data sonification was contextualized in time and space by calculating and visualizing the location of the spacecraft in relation to the other planets during the Mars mission. The finished work is a unique and powerful means of communicating the presence and risk of space radiation, accessible by people of all ages and scientific backgrounds

Richard Snow↗
NASA NTRS2000

A Lifetime of Geodesy and Geophysics: In Rememberence of Bill Kaula

In the early 1960's the secrets that knowledge of the Earth's gravity field would eventually reveal about the processes that govern our planet were yet to be appreciated. It was the beginning of a new science known as space geodesy, which arose at a time when most efforts were devoted to understanding how to extract precise measurements of Earth structure and motions from an orbiting spacecraft. Bill Kaula was central to that beginning and showed the way for many who were to follow, both in time and in the development of approaches most likely to yield results. Bill laid out the theory, analyzed the data, and argued strenuously for a spacecraft mission devoted to measuring gravity to make it all come true in the way he knew it really could. That mission, GRACE, was a long time coming and Bill would not see its final staging, but his influence in making it happen was everywhere. With time, the concepts for measuring the static gravity field of the Earth and terrestrial planets became well advanced, although not universally agreed upon, and certainly not by Bill, who was always eager to argue and challenge traditional methods and thinking. The extension of space geodetic techniques to the planets and the development of new techniques to measure time variations in gravity have recently brought geodesy even closer to the geophysical processes that Bill sought to understand. This presentation will contain a little geodesy, a little history, and a little reminiscing about the leader in our field.

Smith, David E.↗
NASA NTRS2008

The Cassini Live Update Process

The Cassini orbiter is an international science mission to the Saturnian system with 12 science instruments onboard. The Cassini spacecraft lacks a scan platform, which means the entire spacecraft must be rotated to control pointing of any one instrument's boresight. The resulting complex sequences of commands are built beginning many months before execution onboard. Late ephemeris updates from improved navigation data (i.e. after an orbital trim maneuver) often result in pointing commands in the sequence no longer being accurate enough to obtain the desired science observation. This paper will provide an overview of how Cassini uses live updates to address this potential loss of data, including the software developed for this process.

Vandermey, Nancy↗
NASA NTRS2019

Assessment and Validation of Collision "Consequence" Method of Assessing Orbital Regime Risk Posed by Potential Satellite Conjunctions

Collision risk management theory requires a thorough assessment of both the likelihood and consequence of potential collision events. Satellite conjunction risk assessment has produced a highly-developed theory for assessing the likelihood of collision but neglects to account for the consequences of a given collision. While any collision may compromise the operational survival of a spacecraft, the amount of debris produced by the potential collision, and therefore the degree to which the orbital corridor may be compromised, can vary greatly among satellite conjunctions. Previous studies leveraged work on satellite collision modeling to develop a method to estimate whether a particular collision is likely to produce a relatively large or relatively small amount of resultant debris. The approximation of the number of debris pieces is dependent on a mass estimation process for the secondary objects utilizing the radar cross section of said object. This study examines the validity of the mass estimation process and establishes uncertainty bounds on the secondary object mass, which will be used to best approximate the possible consequences of a potential collision. This process is then applied to a large set of historical conjunctions to assess the frequency at which possible collisions may significantly augment the orbital debris environment in operational spacecraft.

Collision Consequence↗
NASA NTRS1994

Low encounter speed comet COMA sample return missions

Comets, being considered the most primitive bodies in the solar system, command the highest priority among solar-system objects for studying solar nebula evolution and the evolution of life through biogenic elements and compounds. The study of comets, and more especially, of material from them, provides an understanding of the physical, chemical, and mineralogical processes operative in the formation and earliest development of the solar systems. These return samples will provide valuable information on comets and serve as a rosetta stone for the analytical studies conducted on interplanetary dust particles over the past two decades, and will provide much needed extraterrestrial samples for the planetary materials community since the Apollo program. Lander sample return missions require rather complex spacecraft, intricate operations, and costly propulsion systems. By contrast, it is possible to take a highly simplified approach for sample capture and return in the case of a comet. In the past, we have considered Earth free-return trajectory to the comet, in which passive collectors intercept dust and volatiles from the cometary coma. However, standard short period cometary free-return trajectories results in the comet to the spacecraft encounter speeds in the range of 10 km/s. At these speeds the kinetic energy of the capture process can render significant modification of dust structure, change of solid phase as well as the lost of volatiles components. This paper presents a class of new missions with trajectories with significant reduction of encounter speeds by incorporating gravity assists and deep space maneuvering. Low encounter speed cometary flyby sample return will enable a marked increase in the value of the return science. Acquiring thousands of samples from a known comet and thousands of images of a comet nucleus would be space firsts. Applying new approach in flight mechanics to generate a new class of low encounter speed cometary sample return trajectories opens new possibilities in science. A systematic search of trajectories for the first decade of the twenty-first century will be made. The target encounter speed is for less than 7 km/s to short period comets.

Tsou, P.↗
NASA NTRS2013

Automated Planning of Science Products Based on Nadir Overflights and Alerts for Onboard and Ground Processing

A set of automated planning algorithms is the current operations baseline approach for the Intelligent Payload Module (IPM) of the proposed Hyper spectral Infrared Imager (HyspIRI) mission. For this operations concept, there are only local (e.g. non-depletable) operations constraints, such as real-time downlink and onboard memory, and the forward sweeping algorithm is optimal for determining which science products should be generated onboard and on ground based on geographical overflights, science priorities, alerts, requests, and onboard and ground processing constraints. This automated planning approach was developed for the HyspIRI IPM concept. The HyspIRI IPM is proposed to use an X-band Direct Broadcast (DB) capability that would enable data to be delivered to ground stations virtually as it is acquired. However, the HyspIRI VSWIR and TIR instruments will produce approximately 1 Gbps data, while the DB capability is 15 Mbps for a approx. =60X oversubscription. In order to address this mismatch, this innovation determines which data to downlink based on both the type of surface the spacecraft is overflying, and the onboard processing of data to detect events. For example, when the spacecraft is overflying Polar Regions, it might downlink a snow/ice product. Additionally, the onboard software will search for thermal signatures indicative of a volcanic event or wild fire and downlink summary information (extent, spectra) when detected, thereby reducing data volume. The planning system described above automatically generated the IPM mission plan based on requested products, the overflight regions, and available resources.

Chien, Steve A.↗
NASA NTRS2013

Putting Integrated Systems Health Management Capabilities to Work: Development of an Advanced Caution and Warning System for Next-Generation Crewed Spacecraft Missions

Integrated System Health Management (ISHM) technologies have advanced to the point where they can provide significant automated assistance with real-time fault detection, diagnosis, guided troubleshooting, and failure consequence assessment. To exploit these capabilities in actual operational environments, however, ISHM information must be integrated into operational concepts and associated information displays in ways that enable human operators to process and understand the ISHM system information rapidly and effectively. In this paper, we explore these design issues in the context of an advanced caution and warning system (ACAWS) for next-generation crewed spacecraft missions. User interface concepts for depicting failure diagnoses, failure effects, redundancy loss, "what-if" failure analysis scenarios, and resolution of ambiguity groups are discussed and illustrated.

integrated system management↗
NASA NTRS1999

Lightweight Battery Charge Regulator Used to Track Solar Array Peak Power

A battery charge regulator based on the series-connected boost regulator (SCBR) technology has been developed for high-voltage spacecraft applications. The SCBR regulates the solar array power during insolation to prevent battery overcharge or undercharge conditions. It can also be used to provide regulated battery output voltage to spacecraft loads if necessary. This technology uses industry-standard dc-dc converters and a unique interconnection to provide size, weight, efficiency, fault tolerance, and modularity benefits over existing systems. The high-voltage SCBR shown in the photograph has demonstrated power densities of over 1000 watts per kilogram (W/kg). Using four 150-W dc-dc converter modules, it can process 2500 W of power at 120 Vdc with a minimum input voltage of 90 Vdc. Efficiency of the SCBR was 94 to 98 percent over the entire operational range. Internally, the unit is made of two separate SCBR s, each with its own analog control circuitry, to demonstrate the modularity of the technology. The analog controllers regulate the output current and incorporate the output voltage limit with active current sharing between the two units. They also include voltage and current telemetry, on/off control, and baseplate temperature sensors. For peak power tracking, the SCBR was connected to a LabView-based data acquisition system for telemetry and control. A digital control algorithm for tracking the peak power point of a solar array was developed using the principle of matching the source impedance with the load impedance for maximum energy transfer. The algorithm was successfully demonstrated in a simulated spacecraft electrical system at the Boeing PhantomWorks High Voltage Test Facility in Seattle, Washington. The system consists of a 42-string, high-voltage solar array simulator, a 77-cell, 80-ampere-hour (A-hr) nickel-hydrogen battery, and a constant power-load module. The SCBR and the LabView control algorithm successfully tracked the solar array peak power point through various load transients, including sunlight discharge transients when the total load exceeded the maximum solar array output power.

Soeder, James F.↗
DOE OSTI2025

Code Release for “Unlocking Extreme Space Weather through Advanced Modeling of Legacy Vela Spacecraft” ER

The software being developed for this project has two mains aims. First, a Bayesian Model Calibration (BMC) procedure is being developed to calibrate a spallation model that simulates protons hitting a spacecraft orbiting earth to real data. The procedure will be developed for general data (there is no data release requested as part of this code release). Second, an inverse physics modeling task is being undertaken to map the number of resulting neutrons observed from this process to the expected number of protons that hit the model. This second task is of statistical interest; to publish on it, the code will need to be open source.

Murph, Alexander↗
NASA NTRS1972

Dynamic load simulator

Concepts and techniques for identifying and simulating both the steady state and dynamic characteristics of electrical loads for use during integrated system test and evaluation are discussed. The investigations showed that it is feasible to design and develop interrogation and simulation equipment to perform the desired functions. During the evaluation, actual spacecraft loads were interrogated by stimulating the loads with their normal input voltage and measuring the resultant voltage and current time histories. Elements of the circuits were optimized by an iterative process of selecting element values and comparing the time-domain response of the model with those obtained from the real equipment during interrogation.

Joncas, K. P.↗
NASA NTRS1982

Spacecraft radio frequency subsystem

The historical background for the development of the planetary (RFS) is reviewed, and the performance capabilities of the various functional subassemblies are described. The flight radio frequency subsystem is a valid component for the three spacecraft telecommunications functions of tracking, command, and telemetry. It is the radio and the signal processing equipment residing in the spacecraft that interfaces with the control & data subsystem and performs two-way communications with the Earth-based Deep Space Network. The RFS consists of all the elements for RF reception, demodulation, modulation, and transmission, including those for command detection and telemetry modulation.

Tam, M. K.↗
NASA NTRS1987

The Mission Operations Planning Assistant

The Mission Operations Planning Assistant (MOPA) is a knowledge-based system developed to support the planning and scheduling of instrument activities on the Upper Atmospheric Research Satellite (UARS). The MOPA system represents and maintains instrument plans at two levels of abstraction in order to keep plans comprehensible to both UARS Principal Investigators and Command Management personnel. The hierarchical representation of plans also allows MOPA to automatically create detailed instrument activity plans from which spacecraft command loads may be generated. The MOPA system was developed on a Symbolics 3640 computer using the ZetaLisp and ART languages. MOPA's features include a textual and graphical interface for plan inspection and modification, recognition of instrument operational constraint violations during the planning process, and consistency maintenance between the different planning levels. This paper describes the current MOPA system.

Schuetzle, James G.↗
NASA NTRS1987

The mission operations planning assistant

The Mission Operations Planning Assistant (MOPA) is a knowledge-based system developed to support the planning and scheduling of instrument activities on the Upper Atmospheric Research Satellite (UARS). The MOPA system represents and maintains instrument plans at two levels of abstraction in order to keep plans comprehensible to both UARS Prinicpal Investigators and Command Management personnel. The hierarchical representation of plans also allows MOPA to automatically create detailed instrument activity plans from which spacecraft command loads may be generated. The MOPA system was developed on a Symbolics 3640 computer using the ZETALISP and ART languages. MOPA's features include a textual and graphical interface for plan inspection and modification, recognition of instrument operational constraint violations during the planning process, and consistency maintenance between the different planning levels. This paper describes the current MOPA system.

Schuetzle, James G.↗
NASA NTRS2000

Autonomy for Constellation

The newer types of space systems, which are planned for the future, are placing challenging demands for newer autonomy concepts and techniques. Motivating these challenges are resource constraints. Even though onboard computing power will surely increase in the coming years, the resource constraints associated with space-based processes will continue to be a major factor that needs to be considered when dealing with, for example, agent-based spacecraft autonomy. To realize "economical intelligence", i.e., constrained computational intelligence that can reside within a process under severe resource constraints (time, power, space, etc.), is a major goal for such space systems as the Nanosat constellations. To begin to address the new challenges, we are developing approaches to constellation autonomy with constraints in mind. Within the Agent Concepts Testbed (ACT) at the Goddard Space Flight Center we are currently developing a Nanosat-related prototype for the first of the two-step program.

Truszkowski, Walt↗
NASA NTRS2010

Fault Management Practice: A Roadmap for Improvement

Autonomous fault management (FM) is critical for deep space and planetary missions where the limited communication opportunities may prevent timely intervention by ground control. Evidence of pervasive architecture, design, and verification/validation problems with NASA FM engineering has been revealed both during technical reviews of spaceflight missions and in flight. These problems include FM design changes required late in the life-cycle, insufficient project insight into the extent of FM testing required, unexpected test results that require resolution, spacecraft operational limitations because certain functions were not tested, and in-flight anomalies and mission failures attributable to fault management. A recent NASA initiative has characterized the FM state-of-practice throughout the spacecraft development community and identified common NASA, DoD, and commercial concerns that can be addressed in the near term through the development of a FM Practitioner's Handbook and the formation of a FM Working Group. Initial efforts will focus on standardizing FM terminology, establishing engineering processes and tools, and training.

Fesq, Lorraine M.↗
NASA NTRS2018

A Systems Architecting Methodology Using Bloom’s Taxonomy to Promote Creative Engineering Synthesis

Architecting complex systems requires high-level cognitive processing and extensive knowledge of the system elements, functions, relationships, and constraints. This paper describes a systems architecting methodology implemented through cognitive psychological creative processes using Bloom’s taxonomy as a framework to generate the expert knowledge required to effectively and systematically synthesize new systems. Systems architecting activities were carried out to identify, develop, and capture factual and conceptual knowledge relevant to the system subject matter and functional elements, as well as to facilitate active processing of the knowledge through remembering, understanding, applying, analyzing, evaluating, and creating. Dual channel and limited capacity principles of learning were incorporated into the format of the systems engineering tools developed to assist with information processing and retention. Meta-cognitive strategies associated with memory and creative idea generation were implemented into the methodology to effectively and efficiently develop system alternatives using the full collection of knowledge. Synthesis of an orbiting sample capture and orientation system architecture to enable spacecraft-based on orbit capture of a Mars sample container for a potential Mars Sample Return campaign was used as a case study.

Adajian, Rama↗