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Integrated Ground Supported Systems Equation Processor

Goddard Space Flight Center, Greenbelt, Maryland The Integrated Science Instrument Module (ISIM) Ground Support System (IGSS) Equation Processor (IEP) allows for the general production of “derived” telemetry products in the Raytheon Eclipse ground system used to support the James Webb Space Telescope (JWST) project. The IEP works alongside the Raytheon-provided equation-processing system but provides for support of string data types that the existing equation processing does not support. The string data type production is required to support the manipulation of JWST string telemetry data types, and for the production of string data types to produce readable time conversions from a binary value to year, day, hour, minute, second format that can be directly viewed on real-time telemetry display pages. The user writes equation scripts using the Tool Command Language (TCL) and specifies as part of the definition how the equation is triggered and what the results should look like. The TCL scripting language provides for a fully featured programming language to manipulate the string data in any form imaginable.

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Perilog

Ames Research Center, Moffett Field, California Perilog measures the degree of contextual association of large numbers of term pairs in text to produce network models that capture the structure of the text and, by virtue of Perilog’s validated theory of iconicity, the structure of the domains, situations, and concerns expressed by the author of the text. Given alphanumeric representations of any other sequences in which context is meaningful — such as music or generic sequences — Perilog can derive their contextual structure.

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Build, Assemble, Test (BAT) Planning and Execution Resources Application

NASA’s Jet Propulsion Laboratory, Pasadena, California BAT is a Web-based application used for the assembly and inspection of critical flight and associated ground support hardware for JPL missions that are developed in-house. It is used to capture and communicate data that is unique to a part or assembly that cannot be captured in an engineering drawing or a test procedure. It includes a list of parts and tools, along with specific steps required for building and assembling a piece of hardware.

Posted in: Briefs, TSP, Electronics & Computers

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Tool for Turbine Engine Closed-loop Transient Analysis (TTECTrA)

John H. Glenn Research Center, Cleveland, Ohio The current steady-state performance-based system studies are not adequate to evaluate certain advanced technologies for the challenges associated with meeting the transient performance requirements without better definition and control of component operating margins. Additional dynamic analyses would require more detailed, physics-based, component-level models and controllers in order to better identify dynamic issues that may arise during operation of the engine. The additional complexity in these models increases the effort necessary throughout the design processes, including the system-analysis step. The solution would be a physics-based engine model with full envelope controller. C-MAPSS and C-MAPSS40k are examples of engine models with full envelope controllers, but because they are designed to model a specific engine, they are not good candidates for systems analysis.

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Wald Sequential Probability Ratio Test for Space Object Conjunction Assessment

The decision procedure is based on targets for false alarm and missed detection rates, along with a prior assessment of the risk of collision, which is independent of the orbit determination. Goddard Space Flight Center, Greenbelt, Maryland When a maneuverable spacecraft confronts a potentially unsafe conjunction with another space object, its operators must decide whether to maneuver to mitigate the risk of a collision. Such decisions may not be straightforward, since the operators must balance their confidence in the predictions that detected the conjunction, the actual likelihood of a collision, any risk inherent in performing the maneuver, interruptions to the mission’s ongoing operations, and long-term consequences such as depletion of consumable propellant. The most common metric for assessing the risk associated with a conjunction is the collision probability.

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Next Generation of 3DGRAPE: Flexible Framework for Hypersonic Navier-Stokes Shuttle Orbiter Meshes

High-fidelity grids were generated rapidly using an assembly line approach with teamwork among NASA centers. Langley Research Center, Hampton, Virginia The class of 3DGRAPE codes is designed to generate volume grids using iterative methods to solve the non-linear, nonhomogeneous, elliptic partial differential heat equation with heat sources. The solution to the heat equation develops three-dimensional discrete points within a domain outside or inside a vehicle where fluid flow is simulated with Computational Fluid Dynamics (CFD). The latest version in this class of software is the 3DGRAPE/AL:V3, version 3 of the Three-Dimensional Grids about Anything by Poisson’s Equation with Upgrades from NASA Ames and Langley computer programs. The previous version, 3DGRAPE/AL:V2 [“Further Improvement in 3DGRAPE,” (LAR-16415-1) NASA Tech Briefs, Vol. 28, No. 9 (September 2004), p. 50], was advanced through the development of a new block-to-block boundary condition that guarantees C-I continuity between adjacent blocks sharing a common block face. Until this condition was developed, matching block faces were only created by projecting a straight line from one cell into each block from the matching face, thereby changing the initial grid that defines a structured multiple block system.

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Delay Tolerant Link State Routing MACHETE Model

NASA’s Jet Propulsion Laboratory, Pasadena, California This software models the Delay Tolerant Link State Routing protocol. It runs inside the QualNet network simulator, and allows injecting of external bundles when running in emulation mode. It leverages QualNet’s library of networking protocols and JPL’s CCSDS models.

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