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The orbiting carbon observatory (OCO) is a NASA Earth system science pathfinder (ESSP) mission that is currently under development at the Jet Propulsion Laboratory (JPL). OCO will make global, space-based measurements of atmospheric carbon dioxide (CO2) with the precision, resolution, and coverage needed to characterize regional-scale sources and sinks of this important greenhouse gas. The observatory...
The Mars reconnaissance orbiter (MRO) Ka-band demonstration has been indefinitely postponed and its objectives must now be met through other means. One of these objectives is the evaluation of the continuity and completeness performance of the deep-space Ka-band link for different link design criteria. To meet this objective, the data from the water vapor radiometers (WVR) and the advanced water vapor...
NASA's Space Communication and Navigation (SCaN) office has been designing an agency-wide space communication and navigation architecture to support NASA space exploration and science missions out to 2030. SCaN chartered a study in 2007 to select codes, modulations, multiple access techniques and link protocols for this architecture. The study was conducted by Goddard Space Flight Center, the Jet...
NASA has undertaken a study to recommend and justify coding, modulation, and link protocol (CMLP) designs for the Space Communications and Networking (SCaN) office. This paper reports on the coding part of the CMLP study, which is chartered with identifying the forward error correction (FEC) codes suitable for NASA space exploration and science missions through 2030.
Over the past fifteen years, Goddard Space Flight Center has developed several successful science missions in-house: the Wilkinson Microwave Anisotropy Probe (WMAP), the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE), the Earth Observing 1 (EO-1), and the Space Technology 5 (ST-5) missions, several Small Explorers, and several balloon missions. Currently in development are the Solar...
The need for automated instrument product (experiment data records and reduced data records) generation is driven by mission performance requirements such as high data volumes, rapid product turnaround and product complexity combined with the need to keep operational costs low. Historically, missions have independently developed unique capabilities to manage production of critical instrument products...
False alarms in legacy aircraft diagnostic systems have negatively impacted fleet maintenance costs and mission readiness. As the industry moves towards more advanced prognostic and health management (PHM) solutions, a reduction in false alarms is needed to reduce the cost and readiness burdens that have plagued legacy systems. It is therefore important to understand why these false alarms occur and...
The latest advances in survival analysis have been centered on multivariate systems. Multivariate survival analysis has two major categories of models: one is multi-state modeling; the other is shared frailty modeling. Multi-state models, although formulated differently in both fields, have been extensively studied in reliability analysis in the context of Markov chain analysis. In contrast, shared...
Software is an increasingly critical component in aerospace systems, and automated software testing technologies that use formal methods are emerging as a new type of ground data system for verifying and validating software changes. With each change made to software for use in operational settings, there is the opportunity for new bugs to be introduced that can cause potentially catastrophic results...
Instrument ground support equipment (IGSE) software reuse from one mission to the next is a practical necessity in the aerospace industry. Schedule and budget constraints often dictate significant reuse of heritage designs when proposing, designing and implementing IGSE for new missions. This practice often results in a tight coupling between the IGSE designs of successive missions. In situations...
As human kind prepares for further exploration of our solar system it is crucial to consider the wide range of potential psychological and physiological effects brought about by long duration spaceflight.12 This paper reviews efforts to address these effects in three areas: human factors design, physiological health, and psychosocial issues. Human factors design considerations include increasing user-friendliness...
Over the past 20 years, there has been much work in the area of model-based diagnosis (MBD). By this we mean diagnosis systems arising from computer science or artificial intelligence approaches where a generic software engine is developed to address a large class of diagnosis problems. Later, models are created to apply the engine to a specific problem. These techniques are very attractive, suggesting...
Many spacecraft provide an abundance of system status telemetry that is monitored in real time by ground personnel and archived to allow for further analysis. In the flight control room, controllers typically monitor these values using text or graphical displays that incorporate individual parameter limit checking or simple trend analysis. Recent developments in data mining techniques for anomaly...
This paper presents the first, very promising results of the automated troubleshooting of satellite communication ground equipment (ATSIG) project, which is a research project conducted by Wirtek and University of Malaga and supported by European Space Agency. The project develops a novel concept for automating the troubleshooting process of a Satcom network operator. The work presented contains a...
The phrase "planning and scheduling" represents a class of problems where a resource in limited supply is to be optimally applied. Planning and scheduling problems are accommodated by a branch of mathematics known as operations research. The goal of operations research technology is to find a solution to a known set of conditions such that some minimum "cost" or maximum "profit"...
The numerous benefits of automatic application code generation are widely accepted within the software engineering community. A few of these benefits include raising the abstraction level of application programming, shorter product development time, lower maintenance costs, and increased code quality and consistency. Surprisingly, code generation concepts have not yet found wide acceptance and use...
Time-based command sequencing is the traditional paradigm for control of spacecraft and rovers in NASA's robotic missions, but this paradigm has been increasingly strained to accommodate today's missions. Goal-based control is a new paradigm that supports time-driven and event-driven operation in a more natural way and permits a melding of sequencing and fault protection into a single control paradigm...
The complexities of current space programs result in similar databases used across a widely distributed team. A centralized database can be an excellent way to streamline data interfaces between the distributed users. This centralization often results in confusion about the process by which data is collected and distributed, increases cost, and without proper architecture can introduce unnecessary...
Autonomous docking operations are a critical aspect of unmanned satellite servicing missions. Tender spacecraft must be able to approach the client spacecraft, maneuver into position, and then attach to facilitate the transfer of fuel, power, replacement parts, etc. The philosophical approach to the docking system design is intimately linked to the overall servicing mission. The docking system functionality...
In high contrast imaging system, semi-static, non-common path wave front errors not sensed by the active wave front sensor in an adaptive optics system will 'leak' around the coronagraph and lead to focal plane speckles that will mask exo-planets. Sensing and controlling these speckles is an absolute necessity for direct detection of planets from the ground. The next generation of AO systems that...
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