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This paper discusses how the Manufacturing and Operations Information System (MOIS) is being enhanced to interoperate with the Dynamic Object-Oriented Requirements Systemtrade (DOORStrade) and the Integrated Test and Operations System (ITOS) to provide an automated verification environment called the Integrated Satellite Test Suite (ISTS). This suite facilitates the development of test procedures;...
This paper describes the investigation, analyses, and tests carried out to determine the source of an unknown "phantom" disturbance torque that was saturating the control moment gyroscopes, causing loss of attitude control of the International Space Station during Russian extravehicular activities. Exhaustive flight data analyses, analytic simulations for flight data reconstruction, and...
The Jet Propulsion Laboratory's Deep Impact (DI) Project was a smashing success with its successful Impact and Flyby Encounter on July 4, 2005 (UTC). Deep Impact launched the flight system, consisting of two spacecraft, on January 12, 2005 for an Encounter with comet Tempel 1 just 6 months later. The two spacecraft, known as the Flyby and the Impactor, were separated 24 hours prior to Encounter, whereby...
Achieving a sustainable exploration program requires development of a foundation of knowledge, validated technologies, and tools that support safe/reliable, affordable, effective, and flexible systems. Furthermore, the exploration program requires new paradigms in program execution and mission operations to meet both technical and budgetary challenges of space exploration missions. New technologies...
Prognostic health monitoring (PHM) is an important element of condition-based maintenance and logistics support. The accuracy of prediction and the associated confidence in prediction, greatly influences overall performance and subsequent actions either for maintenance or logistics support. Accuracy of prognosis is directly dependent on how closely one can capture the system and component interactions...
Over the past six years, Smiths and BAE Systems have launched collaborative work to evolve a certifiable practical SPHM system. The collaborative work has built on BAE Systems' vast advanced technology experience and on Smiths' unique experience that has produced intelligent Fleet and Usage Management Software (FUMStrade) including fusion, prognostic and decision support algorithms combining model-based...
SCOS-2000 is ESA's standard kernel for spacecraft command and control systems, hiflyreg is a suite of products based on SCOS-2000 commercialized in the US by GMV. NASA's GMSEC defines a standard middleware architecture that can be used by the ground segment of different space missions. The purpose of GMSEC is to easily integrate new flight operations components into Mission Control Centers. This paper...
hiflyViews is the new generation telemetry visualization component of hiflyreg, GMV's complete monitoring and control solution for satellite fleet operations based on ESA's SCOS-2000 technology. As described in this paper, hiflyViews represents a leap forward in satellite telemetry visualization as follows: flexible data access: data can be accessed in live or retrieval; archived data can be fetched...
This paper describes the results of a significant research and development effort conducted at NASA Ames Research Center to develop new text mining algorithms to discover anomalies in free-text reports regarding system health and safety of two aerospace systems. We discuss two problems of significant import in the aviation industry. The first problem is that of automatic anomaly discovery concerning...
Prognostics and health management (PHM) is believed to become a built-in capability for the next generation military aircraft, e.g., Joint Strike Fighter (JSF). Health monitoring for gas turbine engines is certainly an essential component for such PHM systems. This paper presents a technique of detecting and diagnosing disk cracks of gas turbine engines under spin testing by analyzing the shaft displacement...
The drive train of a helicopter is a flight critical system in which the transmission of power results in both lift and thrust via a complex set of gears and shafts. Maintenance cost of this aircraft system is typically high due to the large damaging forces directed through these components. Consequently, monitoring the health of the drive train can potentially enhance flight safety and reduce operating...
Condition-based maintenance (CBM) of complex military vehicles or industrial machines presumes the capability to correctly detect faults in components or subsystems. Faults are malfunctions that are observed in the monitoring system. Two types of errors can occur during automated fault detection: (1) missed detections or (2) false alarms. The practical consequence of either type of error is that a...
Strain gages developed using high-definition direct write technology enable direct bonding to substrates without an adhesive layer, so greater shear forces may be faithfully transmitted and thicker, more robust conductors may be used for strain-sensing. Effects of hysteresis, creep, and temperature limitations common to adhesively-bonded gages can also be mitigated. Manufacture and installation of...
Diagnostic architectures that fuse outputs from multiple algorithms are described as knowledge fusion or evidence aggregation. Knowledge fusion using a statistical framework such as Dempster-Shafer (D-S) has been used in the context of engine health management. Fundamental assumptions made by this approach include the notion of independent evidence and single fault. In most real world systems, these...
The Goodrich Integrated Mechanical Diagnostics Health and Usage System (IMD-HUMS) mechanical diagnostics functionality is the integration of disparate subsystems. When the aircraft is in the appropriate capture window, the primary processing unit (PPU), commands the vibration processing unit (VPU) to capture vibration data and a tachometer reference. This time domain data is processed by standard...
Data from mobile and stationary sensors will be vital in planetary surface exploration. The distribution and collection of sensor data in an ad-hoc wireless network presents unique challenges. Some of the conditions encountered in the field include: irregular terrain, mobile nodes, routing loops from clients associating with the wrong access point or repeater, network routing reconfigurations caused...
It is increasingly appreciated that models of combat and social-political behavior can be informative, helping us to anticipate possible future developments and the possible implications of contemplated actions. However, these models often cannot be relied upon to make predictions as accurate as those possible with models that have been developed in engineering and the physical sciences. Consequently,...
DARPA initiated a six-month Pre-Conflict Anticipation and Shaping (PCAS) initiative to demonstrate the utility of quantitative and computational social science models (Q/CSS) applied to assessing the instability and failure of nation-states. In this program ten different teams of Q/CSS researchers and practitioners developed nation state instability models and then applied them to two different countries...
The creation of quality software depends on the existence of a quality software design. In particular, it is important to identify inconsistencies that might be injected at the design level. We have developed a common ontology that integrates software specification knowledge and software design knowledge in order to facilitate the interoperability of formal requirements modeling tools and software...
Statically compiled and strongly typed languages (Java, C#) have demonstrated their ability to produce robust, easily maintainable applications. Many of us accept this statement as dogma, not open to question. Whether true or not, most of us would agree that such languages as Java have changed forever the way we develop and deploy applications. In this paper, we propose that in order to evolve the...
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