System Engineering and Integration (SE&I) The Constellation SE&I Office is chartered with executing the systems-based engineering activities that are required to define and integrate the level-2 mission support requirements for the Constellation architecture. The approach is designed to ensure the successful integration of NASA’s systems with an emphasis on safety, increased performance, and cost reduction. ESP provides support to the following groups: Safety, Reliability, and Quality Assurance (SR&QA) SR&QA encompasses activities that contribute to ensuring the highest possibility of mission success. One of these disciplines is software assurance, focusing on the processes and procedures that will ensure that software, across the Constellation architecture, functions reliably and safely to minimize potential risks associated with loss of life or the mission. Lunar Surface System Project In the area of Lunar Surface Systems, GSFC is engaged in the definition and development of the Communications and Navigation aspects of the lunar architecture. Since its inception, the Center has led human space¬flight and near-Earth robotic communications/tracking and navigation efforts for the Agency and is leveraging its decades of expertise in these areas to benefit Constellation and other Exploration Systems Mission Directorate (ESMD) initiatives. Under the management of the Exploration Systems Project, the Center is already leading two critical LSS domains: Lightweight Structures NASA has historically relied on traditional aeronautical materials such as alloys of aluminum and titanium for the bulk of a spacecraft's structure. These materials provide excellent strength, workability, and relatively low cost. However, there are newer materials, such as carbon fiber-reinforced polymers (CFRP), meta-materials and nano-enhanced materials, which can offer significantly higher strength to mass ratios, lower coefficients of thermal expansion, and even tailor-able electrical and thermal properties that offer dramatic advantages for spacecraft applications. Lightweight inflatable structures utilizing advanced materials can also offer major mass savings. These flight program applications have more recently been supplemented by selected IRAD funded activities focusing on complex CFRP structures and nano-impregnated structural materials, which offer the possibility of materials that are both lightweight and have "tailored properties". Additionally, there was the recent NESC funded effort led by Goddard and the Langley Research Center to design, build, and test a full size Composite Crew Module, which is a CFRP version of the Orion capsule. This effort was very successful. Hence, a number of examples of advanced lightweight materials and structures for space applications exist, and material data bases have been developed and analytical models verified. Goddard has played a key role in leading this technology development effort, and now has a robust composite design, analysis, fabrication, bonded assembly, and integration capability. The opportunities for further development of lightweight materials and structures are both real and quite significant. Cryogenics -- Fluid Management Goddard Space Flight Center (GSFC) is leveraging its unparalleled experience with long-life in-space cryogen storage systems to develop game-changing cryogenic fluid management (CFM) technologies for long-term storage of cryogenic propellants - a crucial capability that enables solar system exploration. GSFC is leading an effort to demonstrate a thermodynamic cryogen subcooler (TCS) that will provide a compact method for subcooling and maintaining cryogenic propellants on the launch pad for upper-stage or propellant-depot supply applications. The TCS will be compact, incur low transfer losses, and have low peak power and consumables usage. Subcooling and thermodynamic maintenance on the launch pad will ease launch logistics and increase operational flexibility without adding any significant launched mass. After launch, the heating of the subcooled cryogenic propellant allows it to absorb the large quantities of energy that leak into the tank. During this period of heating of the subcooled cryogen there will be no loss of the propellant due to venting. In fact, the TCS would triple the in-space vent-free hydrogen storage time. This technology will augment other CFM technologies and buy tolerance for CFM imperfections and uncertainties. Other areas of focus for GSFC CFM technologies include technologies related to the co-storage of cryogenic propellants, distributed cooling, passive storage innovations involving multi-layer insulation, active storage concepts involving cryocoolers and the development of cryogenic fluid transfer couplings.
This group within ESP is engaged in activities that are broad in scope and support the development of program-wide policy and definition of high-level requirements. In the area of software assurance, ESP is involved in a wide range of activities, such as influencing designs, acquisition approaches, fabrication plans, and risk management. The team continues to work closely with engineering early in the development process, focusing on key issues such as software safety; testing and evaluation; software probabilistic risk modeling; and ultra-reliability at venues including program-level boards, panels, symposia/working group meetings as well as flight hardware reviews.
Communications Infrastructure: Goddard’s Communications, Standards and Technology Laboratory (CSTL) is currently supporting modeling and simulation efforts to demonstrate Command, Control, Communications and Information interoperability and standards-based Internet Protocol communications. For the lunar surface scenarios currently envisioned, the CSTL incorporates the use of wireless technologies, lunar surface communications base stations, lunar relays, Earth ground stations and network-focused mission control functions.
Over the past 2 decades Goddard has demonstrated the potential for lightweight structures by using advanced composites in numerous flight programs. These include WMAP (a gamma alumina/epoxy design for low conductance), GLAST (a low atomic number composite design for gamma ray transparency), SDO (a composite optical bench for dimensional stability), HST (a composite optical bench for Wide Field Camera 3), JWST (a hybrid composite truss structure optimized for cryogenic environment), and numerous other examples. Many of these applications have been driven by the need for the dimensional stability or transparency to various kinds of radiation that composites can offer.
GROWING UP AT GODDARD: SHUTTLE SMALL PAYLOADS LAUNCHED CAREERS OF MANY
