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Solar energetic particle events (SEPs) are a naturally occurring phenomenon in which subatomic particles are radiated from the sun. Astronauts in deep space could be subjected to significant radiation exposures due to these events. The dose is usually received over approximately a 20-40 hour interval. The effects of these particles could be mitigated by an early detection and warning system, which...
A meta-stable helium (MSHe) extraction method has been developed for In Situ chemical analysis of rocks and soils. MSHe provides soft-ionization and desorption of organics from soil and rocks without the use of solvents or high temperatures. This enables rapid, simple and effective extraction of analytes for very sensitive chemical analysis. The work presented extends the MSHe sampling from mass spectroscopy...
As the first of the new Mars Scouts missions, the Phoenix project was selected by NASA in August of 2003. Four years later, almost to the day, Phoenix was launched from Cape Canaveral Air Station and successfully injected into an interplanetary trajectory on its way to Mars. On May 25, 2008 Phoenix conducted the first successful powered decent on Mars in over 30 years. This paper will highlight some...
Planning and scheduling for space operations entails the development of applications that embed intimate domain knowledge of distinct areas of mission control, while allowing for significant collaboration among them. The separation is useful because of differences in the planning problem, solution methods, and frequencies of replanning that arise in the different disciplines. For example, planning...
The Deep Impact Flyby spacecraft completed its prime mission in August 2005. It was reactivated for a mission of opportunity add-on called EPOXI on September 25, 2007. The first portion of EPOXI, called EPOCh (Extra-solar Planetary Observation & CHaracterization), occurred from January 21, 2008 through August 31, 2008. Its purpose was to characterize transiting hot-Jupiters by measuring the effects...
In late 2006, NASA's Constellation Program (CxP) sponsored a study to examine the feasibility of sending a piloted Orion spacecraft to a near-Earth object (NEO - in the broadest definition these are small, primitive bodies that cross Earth's orbit; the most likely and suitable targets for the Orion are those NEOs in heliocentric orbits similar to Earth's). One of the significant advantages of this...
Using empirical methods, both the intentions of methodologies which use models for the development of software-centric, distributed, real-time systems and the issues impeding systems and software engineers in the usage thereof are presented. The capabilities required of model-driven methodologies and of practitioners to enable successful model-driven development are presented and each capability is...
In this paper, we describe our approach and initial results on modeling, detection, and tracking of terrorist groups and their intents based on multimedia data. While research on automated information extraction from multimedia data has yielded significant progress in areas such as the extraction of entities, links, and events, less progress has been made in the development of automated tools for...
Mars Science Laboratory (MSL), NASA's next mission to Mars, will deploy a large rover carrying a battery of eleven science instruments, representing a wide variety of payload types. The rover's flight software (FSW) has the task of monitoring, commanding, collecting, managing and in some cases calibrating data from these instruments. Though the instruments represent a large variety of requirements,...
The role of flight software in the spacecraft is becoming more essential if missions are to be considered successful. To realize more reliable and continuous independent verification and validation (IV&V) and improve the dependability of flight software, a systems engineering process called Model-based IV&V (MBIVV) was developed and has been applied to flight software for several years. This...
Damage to compressor blades is of critical importance in military aircraft engines. Irregular movements of throttle settings are mandatory requirement for pilots to perform various air combat maneuvers in military aircraft. It leads to excessive stresses on engine compressor blades in various flight regimes. Aircraft are also required to fly in varying atmospheric conditions ranging from negative...
The primary source of electric propulsion development throughout NASA is managed by the In-Space Propulsion Technology Project at the NASA Glenn Research Center for the Science Mission Directorate. The objective of the Electric Propulsion project area is to develop near-term electric propulsion technology to enhance or enable science missions while minimizing risk and cost to the end user. Major hardware...
This paper discusses the structure of a multi modal control framework for generation and control of aggressive maneuver profiles for agile unmanned vehicles. It is shown that any arbitrary flight maneuver can be decomposed into simpler flight modes and modal parameters, which are derived from combat maneuvers and aerobatics. Feasible maneuver generation problem is complicated by both sequence of the...
Autonomous deconfliction capability is crucial to the successful deployment of unmanned aircraft systems (UAS) in most of their envisioned application scenarios. Civil and military applications of UAS demand ever-decreasing levels of human involvement and oversight, hence, UAS need to grow in autonomy. Autonomous deconfliction is a capability that is not only essential for the UAS's self-preservation,...
Autonomous aerial refueling requires a high level of accuracy and integrity. A great deal of research has been conducted in this problem area and has successfully demonstrated techniques with sufficient accuracy for fully autonomous refueling. Unfortunately, significantly less research has focused on the integrity of the relative navigation solution, especially in the presence of degraded sensor operation...
Experimental angular distributions of high-energy primary ions in the near-field region of a small Hall thruster between 50-200 mm downstream of the thruster exit plane at a range of centerline angles have been determined using a highly-collimated, energy-selective diagnostic probe. The measurements reveal a wide angular distribution of ions exiting the thruster channel and the formation of a strong,...
This paper provides a physically-based model for design and optimization of a fuel cell powered electric propulsion system for an Unmanned Aerial Vehicle (UAV). Components of the system include a Solid Oxide Fuel Cell (SOFC) providing power, motor controller, Brushless DC (BLDC) motor, and a propeller. The simulation allows an operator to select constraints and explore design trade-offs between components,...
This paper outlines a technique for operational calibration of mixed-signal integrated circuits (IC) using a configurable analog transistor (CAT). The robustness obtained using this technique show a significant improvement over conventional approaches by using a CAT in the most appropriate sections of the design. This approach demonstrates significant benefits for operational calibration compared...
Autonomous capability in space systems is rapidly becoming a necessity for continued research and exploration. While these systems have traditionally behaved as passive observers, their remoteness and unique access to unexplored environments will likely result in future systems that behave more like active agents employed on our behalf. We may still determine the larger mission goals and priorities,...
Providing flexible satellite communications through frequency- and waveform-agile onboard processing is an emerging trend for missions such as the Air Force's Operationally Responsive Space (ORS). Data packet routing features that seek to improve network flexibility and performance by going beyond traditional ldquobent piperdquo platforms are being leveraged to meet the objectives of ORS. The Programmable...
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