Problems in the thermal design of spacecraft.
Spacecraft thermal design problems including computer programs, thermal control coatings, testing, etc
SEARCH · Search NASA
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Spacecraft thermal design problems including computer programs, thermal control coatings, testing, etc
The Spacecraft Design Course is the capstone design class for the M.S. in astronautics at the Naval Postgraduate School. The Fall 92 class designed a spacecraft for the Near Earth Asteroid Rendezvous Mission (NEAR). The NEAR mission uses a robotic spacecraft to conduct up-close reconnaissance of a near-earth asteroid. Such a mission will provide information on Solar System formation and possible space resources. The spacecraft is intended to complete a NEAR mission as a relatively low-budget program while striving to gather as much information about the target asteroid as possible. A complete mission analysis and detailed spacecraft design were completed. Mission analysis includes orbit comparison and selection, payload and telemetry requirements, spacecraft configuration, and launch vehicle selection. Spacecraft design includes all major subsystems: structure, electrical power, attitude control, propulsion, payload integration, and thermal control. The resulting spacecraft demonstrates the possibility to meet the NEAR mission requirements using existing technology, 'off-the-shelf' components, and a relatively low-cost launch vehicle.
Design criteria for integrating electric propulsion system into SERT 2 spacecraft and future spacecraft designs
Voyager spacecraft thermal control design noting heat rejection louvers and multilayer insulation
Spacecraft control algorithms must know the expected spacecraft response to any command to the available control effectors, such as reaction thrusters or torque devices. Spacecraft control system design approaches have traditionally relied on the estimated vehicle mass properties to determine the desired force and moment, as well as knowledge of the effector performance to efficiently control the spacecraft. A pattern recognition approach can be used to investigate the relationship between the control effector commands and the spacecraft responses. Instead of supplying the approximated vehicle properties and the effector performance characteristics, a database of information relating the effector commands and the desired vehicle response can be used for closed-loop control. A Monte Carlo simulation data set of the spacecraft dynamic response to effector commands can be analyzed to establish the influence a command has on the behavior of the spacecraft. A tool developed at NASA Johnson Space Center (Ref. 1) to analyze flight dynamics Monte Carlo data sets through pattern recognition methods can be used to perform this analysis. Once a comprehensive data set relating spacecraft responses with commands is established, it can be used in place of traditional control laws and gains set. This pattern recognition approach can be compared with traditional control algorithms to determine the potential benefits and uses.
Spacecraft control algorithms must know the expected vehicle response to any command to the available control effectors, such as reaction thrusters or torque devices. Spacecraft control system design approaches have traditionally relied on the estimated vehicle mass properties to determine the desired force and moment, as well as knowledge of the effector performance to efficiently control the spacecraft. A pattern recognition approach was used to investigate the relationship between the control effector commands and spacecraft responses. Instead of supplying the approximated vehicle properties and the thruster performance characteristics, a database of information relating the thruster ring commands and the desired vehicle response was used for closed-loop control. A Monte Carlo simulation data set of the spacecraft dynamic response to effector commands was analyzed to establish the influence a command has on the behavior of the spacecraft. A tool developed at NASA Johnson Space Center to analyze flight dynamics Monte Carlo data sets through pattern recognition methods was used to perform this analysis. Once a comprehensive data set relating spacecraft responses with commands was established, it was used in place of traditional control methods and gains set. This pattern recognition approach was compared with traditional control algorithms to determine the potential benefits and uses.
The Voyager spacecraft represents the state-of-the-art in proven long-life planetary spacecraft. Like its predecessors, the Voyager system design reflects the influence of mission and science requirements, lifetime considerations, environmental factors, technology readiness, hardware availability, and hardware cost. This paper presents the Voyager hardware and software system designs within the context of these design drivers. Major departures from the 'baseline design' are discussed revealing the underlying factors that shaped the final design. Finally, with the benefit of 5 years of test and inflight operational experience, a critical assessment of the design and design methods is made and suggestions are offered to improve similar future efforts.
Meteoroid protection system designs for optimum orbital space laboratories and manned interplanetary spacecraft
The March, 2012 issue of Aerospace America stated that ―the near-to-medium prospects for applying advanced propulsion to create a new era of space exploration are not very good. In the current world, we operate to the Moon by climbing aboard a Carnival Cruise Lines vessel (Saturn 5), sail from the harbor (liftoff) shedding whole decks of the ship (staging) along the way and, having reached the return leg of the journey, sink the ship (burnout) and return home in a lifeboat (Apollo capsule). Clearly this is an illogical way to travel, but forced on Explorers by today's propulsion technology. However, the article neglected to consider the one propulsion technology, using today's physical principles that offer continuous, substantial thrust at a theoretical specific impulse of 1,000,000 sec. This engine unequivocally can create a new era of space exploration that changes the way spacecraft operate. Today's space Explorers could travel in Cruise Liner fashion using the technology not considered by Aerospace America, the novel Dusty Plasma Fission Fragment Rocket Engine (FFRE). This NIAC study addresses the FFRE as well as its impact on Exploration Spacecraft design and operation. It uses common physics of the relativistic speed of fission fragments to produce thrust. It radiatively cools the fissioning dusty core and magnetically controls the fragments direction to practically implement previously patented, but unworkable designs. The spacecraft hosting this engine is no more complex nor more massive than the International Space Station (ISS) and would employ the successful ISS technology for assembly and check-out. The elements can be lifted in "chunks" by a Heavy Lift Launcher. This Exploration Spacecraft would require the resupply of small amounts of nuclear fuel for each journey and would be an in-space asset for decades just as any Cruise Liner on Earth. This study has synthesized versions of the FFRE, integrated one concept onto a host spacecraft designed for manned travel to Jupiter's moon, Callisto, and assessed that round trip journey. This engine, although unoptimized, produced 10 pounds force of thrust at a delivered specific impulse of 527,000 seconds for the entire 15-year mission while providing enormous amounts of electrical power to the spacecraft. A payload of 60 metric tons, included in the 300 metric ton vehicle, was carried to Callisto and back; the propellant tanks holding the 4 metric tons of fuel were not jettisoned in the process. The study concluded that the engine and spacecraft are within today's technology, could be built, tested, launched on several SLS (Space Launch System) (or similar) launchers, integrated, checked out, moved to an in-space base such as at a Lagrange point and operated for decades.
Mechanical and thermal properties of materials for five spacecraft boom designs
Calorimeter design for spacecraft nickel cadmium battery thermal output measurements
Thermal and mechanical properties of materials for spacecraft booms design
Subsystems development in proposed Voyager spacecraft design
Design concepts for deployable spacecraft structures are examined with particular emphasis on mass/area optimization, stowability, and assembly, and the relations of these requirements to functional design parameters. Component and modular concepts for platforms and reflectors, structural configurations for long columns, pretension columns, and joint concepts are discussed. A brief overview of astronaut and automated assembly studies is included.
The slide presentation examines advanced technologies in spacecraft design, space solar power primary payload options, modular spacecraft design, and spacecraft compatible with medium ELV performance. The discussion of advanced technologies in spacecraft design includes power subsystem sized to satisfy all near-term spacecraft power needs, spacecraft bus provides test-bed for maturing technologies, and no insurmountable technical hurdles. The discussion of space solar power primary payload options examines large envelope with standard interfaces reserved for high-power payload. The discussion of modular spacecraft design includes upgrade opportunities, capability for mission tailoring, and bus qualified for most launch vehicles. This discussion of spacecraft compatible with medium ELV performance includes mass capability to ISS orbit and fairing capability for large payloads on the bus.
Spacecraft design for Voyager mission
Design equations for large angle three-axis attitude servomechanism for controlling spacecraft
The design of a human rated spacecraft is a complex and costly process requiring the integrated assessment of many individual criteria. Historically, it has been difficult to include in that integrated assessment the design s full impact on the flight operations community and its costs. The unique "operability requirements" have not been well understood, nor has there been a well-defined set of criteria for assessing operability. As a result, flight operations organizations and program managers are often faced with difficult and costly operations phase implementations. In response, the Mission Operations Directorate at NASA s Lyndon B. Johnson Space Center has established a formal technique to evaluate and communicate the operational characteristics of spacecraft system designs for the Constellation Program. This process is not intended to replace or replicate other critical assessments such as risk, reliability and safety assessments. Instead, this new technique adds to the assessment toolset a means to address the concerns and potential cost drivers that are unique to the operational phase of a program and the flight operations community. This paper describes the implementation and application of this "Spacecraft Flight Operability Assessment Scale" in supporting vehicle design efforts. The six key factors of flight operability are defined, with guiding principles and goals stated for each factor. A standardized rating technique provides feedback that is useful to both the operations and program management communities. Sample assessments of legacy spacecraft, including the Space Shuttle and International Space Station systems, are provided to provide real world examples of this technique s application.