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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.

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At least 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
NASA NTRS1984

Space Station Power System

The strategies, reasoning, and planning guidelines used in the development of the United States Space Station Program are outlined. The power required to support Space Station missions and housekeeping loads is a key driver in overall Space Station design. conversely, Space Station requirements drive the power technology. Various power system technology options are discussed. The mission analysis studies resulting in the required Space Station capabilities are also discussed. An example of Space Station functions and a concept to provide them is presented. The weight, area, payload and altitude requirements on draft and mass requirements are described with a summary and status of key power systems technology requirements and issues.

Baraona, C. R.↗
NASA NTRS1985

A dual spin space station design

A dual spin space station design is described. The space station has a cylindrical solar array that is spun to provide both gyroscopic stiffness to the space station and to stiffen the array structure. The platform is spun at the orbital angular rate. The space station is designed to have gravity gradient and aerodynamic restoring torques. An active control system is used to stabilize the station and store excess angular momentum until it can be removed from the station by magnetic torques.

Paluszek, M. A.↗
NASA NTRS1984

Space Station - Opportunity for international cooperation and utilization

In connection with his announcement regarding the development of a permanently manned Space Station, President Reagan invited the United States' friends and allies to join in the Space Station program. The President's invitation was preceded by more than two years of interaction between NASA and some of its potential partners in Space Station planning activities. Attention is given to international participation in Space Station planning, international cooperation on the Space Station, the guidelines for international cooperation, and the key challenges. Questions regarding quid pro quos are considered along with aspects of technology transfer, commercial use, problems of management, and the next steps concerning the Space Station program.

Pedersen, K. S.↗
NASA NTRS1986

Dynamic characteristics of two 300 kW class dual keel space station concepts

Results from an investigation of the dynamic behavior of a 300 kW class solar dynamic powered, dual kell space station are presented. The purpose of the investigation was to determine and assess the influence of space station truss bay size on station controllability during rigid body attitude adjustment and orbit reboost maneuvers. The dual keel space station concept is defined and two finite element models (one which has a truss bay size of 5m and another with a truss bay size of 9 feet) are described. Rigid and flexible body characteristics of the two space station models are also presented. Finally, results from a transient response analysis, where the stations are subjected to an orbit reboost maneuver, are summarized.

Dorsey, J. T.↗
NASA NTRS1985

Space Station utilization

The essential requirement of the Space Station that the customer be continually involved in all aspects of the program is considered. Potential users of the Space Station need both formal and informal channels into the program at an early stage of the definition process to secure their influence and participation in the development process. Only with this participation can users' needs and requirements be integrated into the design phase to produce 'user friendliness' in the Space Station. A Space Station that is easy and economical to use will generate more users that can take advantage of the available resources. The Space Station must be: a research facility; a satellite servicing and assembly facility; an observatory for terrestrial, solar, and astronomical viewing; and a transportation node for orbit transfer vehicles. NASA intends to see that the Space Station is developed and operated so as to serve its users.

Raney, W. P.↗
NASA NTRS1985

American experiences and perspectives - International cooperation on a permanently manned Space Station

In the late 1960s, NASA contemplated the establishment of a permanently manned Space Station along with the development of the Space Shuttle. After a temporary postponement of the Space Station project, it was finally decided to develop a Space Station and to have it operating by the early 1990s. This station is to serve in a variety of functions which are important for further advances with respect to the utilization of space. The Space Station could even serve as a staging base for trips to the moon and visits to Mars. An international approach is to be taken regarding the development and utilization of the Space Station, giving attention to a cooperation of the U.S. with Canada, Europe, and Japan. The implementation of such a cooperation requires that a number of problems are solved. Basic approaches suitable for achieving such a solution are discussed, taking into account the development of operational schemes which provide for efficient management, while permitting the exercise of diverse 'ownership' rights.

Pedersen, K. S.↗
NASA NTRS1986

Space station support of manned Mars missions

The assembly of a manned Mars interplanetary spacecraft in low Earth orbit can be best accomplished with the support of the space station. Station payload requirements for microgravity environments of .001 g and pointing stability requirements of less than 1 arc second could mean that the spacecraft may have to be assembled at a station-keeping position about 100 meters or more away from the station. In addition to the assembly of large modules and connective structures, the manned Mars mission assembly tasks may include the connection of power, fluid, and data lines and the handling and activation of components for chemical or nuclear power and propulsion systems. These assembly tasks will require the use of advanced automation and robotics in addition to Orbital Maneuvering Vehicle and Extravehicular Activity (EVA) crew support. Advanced development programs for the space station, including on-orbit demonstrations, could also be used to support manned Mars mission technology objectives. Follow-on studies should be conducted to identify space station activities which could be enhanced or expanded in scope (without significant cost and schedule impact) to help resolve key technical and scientific questions relating to manned Mars missions.

Holt, Alan C.↗
NASA NTRS1987

Space station interior noise analysis program

Documentation is provided for a microcomputer program which was developed to evaluate the effect of the vibroacoustic environment on speech communication inside a space station. The program, entitled Space Station Interior Noise Analysis Program (SSINAP), combines a Statistical Energy Analysis (SEA) prediction of sound and vibration levels within the space station with a speech intelligibility model based on the Modulation Transfer Function and the Speech Transmission Index (MTF/STI). The SEA model provides an effective analysis tool for predicting the acoustic environment based on proposed space station design. The MTF/STI model provides a method for evaluating speech communication in the relatively reverberant and potentially noisy environments that are likely to occur in space stations. The combinations of these two models provides a powerful analysis tool for optimizing the acoustic design of space stations from the point of view of speech communications. The mathematical algorithms used in SSINAP are presented to implement the SEA and MTF/STI models. An appendix provides an explanation of the operation of the program along with details of the program structure and code.

Stusnick, E.↗
NASA NTRS1987

Maintenance evaluation for space station liquid systems

Many of the thermal and environmental control life support subsystems as well as other subsystems of the space station utilize various liquids and contain components which are either expendables or are life-limited in some way. Since the space station has a 20-year minimum orbital lifetime requirement, there will also be random failures occurring within the various liquid-containing subsystems. These factors as well as the planned space station build-up sequence require that maintenance concepts be developed prior to the design phase. This applies to the equipment which needs maintenance as well as the equipment which may be required at a maintenance work station within the space station. This paper presents several maintenance concepts for liquid-containing items and a flight experiment program which would allow for evaluation and improvement of these concepts so they can be incorporated in the space station designs at the outset of its design phase.

Flugel, Charles↗
NASA NTRS1987

Speculations on future opportunities to evolve Brayton powerplants aboard the space station

The Space Station provides a unique, low-risk environment in which to evolve new capabilities. In this way, the Space Station will grow in capacity, in its range of capabilities, and its economy of operation as a laboratory and as a center for space operations. Although both Rankine and Brayton cycles, two concepts for solar dynamic power generation, now compete to power the station, this paper confines its attention to the Brayton cycle using a mixture of He and Xe as its working fluid. Such a Brayton powerplant to supply the station's increasing demands for both electric power and heat has the potential to gradually evolve higher and higher performance by exploiting already-evolved materials (ASTAR-811C and molten-Li heat storage), its peak cycle temperature rising ultimately to 1500 K. Adapting the station to exploit long tethers (200 to 300 km long) could yield increases in payloads to LEO, to GEO, and to distant destinations in the solar system. Such tethering of the Space Station would not only require additional power for electric propulsion but also would so increase nuclear safety that nuclear powerplants might provide this power. From an 8000-kWt SP-100 reactor, thermoelectric power generation could produce 300 kWe, or adapted solar-Brayton cycle, 2400 to 2800 kWe.

English, Robert E.↗
NASA NTRS1987

NASA Growth Space Station missions and candidate nuclear/solar power systems

A brief summary is presented of a NASA study contract and in-house investigation on Growth Space Station missions and appropriate nuclear and solar space electric power systems. By the year 2000 some 300 kWe will be needed for missions and housekeeping power for a 12 to 18 person Station crew. Several Space Station configurations employing nuclear reactor power systems are discussed, including shielding requirements and power transmission schemes. Advantages of reactor power include a greatly simplified Station orientation procedure, greatly reduced occultation of views of the earth and deep space, near elimination of energy storage requirements, and significantly reduced station-keeping propellant mass due to very low drag of the reactor power system. The in-house studies of viable alternative Growth Space Station power systems showed that at 300 kWe a rigid silicon solar cell array with NiCd batteries had the highest specific mass at 275 kg/kWe, with solar Stirling the lowest at 40 kg/kWe. However, when 10 year propellant mass requirements are factored in, the 300 kWe nuclear Stirling exhibits the lowest total mass.

Heller, Jack A.↗
NASA NTRS1986

The Space Station program

Likely configurations and goals of the Space Station are delineated. The Station will be a permanent facility designed to be amenable to evolutionary changes. It will be highly automated and user friendly, will be used to perform basic scientific research and observations and to study technologies and processes that may lead to products manufactured in space, and will allow the repair, refurbishment and launch of satellites. The configuration of the Station is being guided by input from future users, which have already helped identify a need to place the laboratory modules at the center of the station to minimize accelerations imparted by other Station activities. Materials which have commercial potential and can only be produced in space after process definition on the Station are discussed, along with NASA efforts to inform industries of the benefits of participation in the program.

Raney, William P.↗
NASA NTRS1987

Raising the AIQ of the Space Station

Expert systems and robotics technologies are to be significantly advanced during the Space Station program. Artificial intelligence systems (AI) on the Station will include 'scars', which will permit upgrading the AI capabilities as the Station evolves to autonomy. NASA-Ames is managing the development of the AI systems through a series of demonstrations, the first, controlling a single subsystem, to be performed in 1988. The capabilities being integrated into the first demonstration are described; however, machine learning and goal-driven natural language understanding will not reach a prototype stage until the mid-1990s. Steps which will be taken to endow the computer systems with the ability to move from heuristic reasoning to factual knowledge, i.e., learning from experience, are explored. It is noted that the development of Space Station expert systems depends on the development of experts in Station operations, which will not happen until the Station has been used extensively by crew members.

Lum, Henry↗
NASA NTRS1986

NASA's space program - Space Station: A status report and a view of its value for space science

The current status of the Space Station program and the proposed configuration, operation, and evolution of the Space Station are described. The Space Station is to be composed of a manned base and two unmanned platforms; the configuration of the Station is dual keel, and the baseline system includes a hybrid power system with photovoltaics providing 25 kW and solar dynamics providing 50 kW. International participation in the development and use of the Space Station, in particular the design of the pressurized modules, is discussed. Intended scientific uses of the Space Station Complex are considered.

Black, David C.↗
NASA NTRS1987

Assessment of mixed fleet potential for space station launch and assembly

Reductions in expected STS flight rates of the Space Shuttle since the 51-L accident raise concerns about the ability of available launch capacity to meet both payload-to-orbit and crew rotation requirements for the Space Station. In addition, it is believed that some phases of Station build-up could be expedited using unmanned launch systems with significantly greater lift capacity than the STS. Examined is the potential use of expendable launch vehicles (ELVs), yet-to-be-developed unmanned shuttle-derived vehicles (SDVs), and international launch vehicles for meeting overall launch requirements to meet Space Station program objectives as defined by the 1986 Critical Evaluation Task Force (CETF). The study concludes that use of non-STS transportation can help meet several important program objectives as well as reduce the total number of STS flights. It also finds, however, that reduction of Space Station-dedicated STS flights below 8 per year forces a reduction in Station crew size assuming the CETF 90 day crew stay time baseline and seriously impairs scientific utilization of the Station.

Deryder, L. J.↗
NASA NTRS1987

The space station assembly phase: Flight telerobotic servicer feasibility, volume 1

The question is addressed which was raised by the Critical Evaluation Task Force (CETF) analysis of the space station: if a Flight Telerobotic Servicer (FTS) of a given technical risk could be built for use during space station assembly, could it save significant extravehicular (EVA) resources. Key issues and trade-offs associated with using an FTS to aid in space station assembly phase tasks such as construction and servicing are identified. A methodology is presented that incorporates assessment of candidate assembly phase tasks, telerobotics performance capabilities, development costs, operational constraints (STS and proximity operations), maintenance, attached payloads, and polar platforms. A discussion of the issues is presented with focus on potential FTS roles: (1) as a research-oriented test bed to learn more about space usage of telerobotics; (2) as a research-based test bed with an experimental demonstration orientation and limited assembly and servicing applications; or (3) as an operational system to augment EVA, to aid the construction of the space station, and to reduce the programmatic (schedule) risk by increasing the flexibility of mission operations. During the course of the study, the baseline configuration was modified into Phase 1 (a station assembled in 12 flights), and Phase 2 (a station assembled over a 30 flight period) configuration.

Smith, Jeffrey H.↗
NASA NTRS1988

Space station mobile transporter

The first quarter of the next century will see an operational space station that will provide a permanently manned base for satellite servicing, multiple strategic scientific and commercial payload deployment, and Orbital Maneuvering Vehicle/Orbital Transfer Vehicle (OMV/OTV) retrieval replenishment and deployment. The space station, as conceived, is constructed in orbit and will be maintained in orbit. The construction, servicing, maintenance and deployment tasks, when coupled with the size of the station, dictate that some form of transportation and manipulation device be conceived. The Transporter described will work in conjunction with the Orbiter and an Assembly Work Platform (AWP) to construct the Work Station. The Transporter will also work in conjunction with the Mobile Remote Servicer to service and install payloads, retrieve, service and deploy satellites, and service and maintain the station itself. The Transporter involved in station construction when mounted on the AWP and later supporting a maintenance or inspection task with the Mobile Remote Servicer and the Flight Telerobotic Servicer is shown.

Renshall, James↗
NASA NTRS1988

Space station full-scale docking/berthing mechanisms development

One of the most critical operational functions for the space station is the orbital docking between the station and the STS orbiter. The program to design, fabricate, and test docking/berthing mechanisms for the space station is described. The design reflects space station overall requirements and consists of two mating docking mechanism halves. One half is designed for use on the shuttle orbiter and incorporates capture and energy attenuation systems using computer controlled electromechanical actuators and/or attenuators. The mating half incorporates a flexible feature to allow two degrees of freedom at the module-to-module interface of the space station pressurized habitat volumes. The design concepts developed for the prototype units may be used for the first space station flight hardware.

Burns, Gene C.↗