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The payload integration process of the Space Transportation System is described. A flight assignment process is outlined and mixed user concepts are discussed along with a user requirements definition. A cargo assessment and flight implementation process are considered. Standard Shuttle services are mentioned.
This bibliography was developed as a first step in the preparation of a monograph on the subject of the aerodynamics of airframe/engine integration of high speed turbine powered aircraft. It lists 1535 unclassified documents published mainly in the period from 1955 to 1980. Primary emphasis was devoted to aerodynamic problems and interferences encountered in the integration process; however, extensive coverage also was given to the characteristics and problems of the isolated propulsion system elements. A detailed topic breakdown structure is used. The primary contents of the individual documents are indicated by the combination of the document's title and its location within the framework of the bibliography.
The Build System comprises the software tools and procedures creating the flight memory load for the Space Shuttle Backup Flight System. The system has six functions: (1) configuration management, which insures that the memory load contains the proper modules, all clearly marked; (2) source translation, which translates the source code into a relocatable machine code; (3) module integration, which combines and assigns memory locations to all the object modules produced in source translation; (4) static code analysis, which verifies the integration process; (5) deliverables generation, which yields release documentation and deliverable items; and (6) release maintenance, which controls all system patches subsequent to release. Further developments will include more automation in the producing of patches from source-code updates and system requirements for tracking.
The development of phosphoric acid fuel cell stack components, fuel selection and processing, integrated system design and development, and large stack design and development were examined.
The effect of a long term micro-gravity environment on the life cycle of plants is unknown. Whether higher plants have evolved to a stage where removal or reduction of gravity is detrimental to plant life cycle and thus fatal to the plant species, is an unanswered question in space plants which were successfully grown through the various stages of their life cycle. Attempts to grow plants as a continuous integral process from seed to seed through one generation were successful until recently. Culture of plants through multiple generations was not accomplished in space nor in ground based studies. The effect of long term simulated weightlessness by growing consecutive generations of plants continuously on clinostats using the cruciferous plants, Arabidopsis thaliana (L.) Heyn. and Cardamine oligosperma Nutt. is being investigated.
The operating principles of an acoustooptic/CCD real-time SAR processor are described, and experimental results are presented. Particular consideration is given to time-and-space integrating processing, the range processor, and the azimuth processor. The interferometric detection scheme is examined in detail.
Both Centralized and Distributed approaches are being evaluated for the installation of Environmental Control and Life Support (ECLS) equipment in the Space Station. In the Centralized facility concept, integrated processing equipment is located in two modules with plumbing used to circulate ECLS services throughout the Station. The Distributed approach locates the ECLS subsystems in every module of the Space Station with each subsystem designed to meet its own module needs. This paper defines the two approaches and how the advantages and disadvantages of each are tied to the choice of Space Station architecture. Other considerations and evaluations include: crew movement, Station evolution and the ducting impact needed to circulate ECLS services from centrally located processing equipment.
Polygeneration system uses existing technology in integrated process to produce liquid hydrogen space-vehicle propellant and secondary products as gaseous nitrogen, electrical energy, and thermal energy. Makes commercial launch services economical. Lowers expected cost of liquid hydrogen by utilizing relatively cheap coal feedstocks and by reducing electrical costs associated with producing liquid hydrogen.
The integration process of the MAST flight system is surveyed. Insight is given into the planned orbital experiment process. The data flow necessary to support the flight operation is outlined.
This presentation is based on the experience gained from having integrated and flown a shuttle middeck experiment. The experiment, which demonstrated filling, expulsion, and fluid behavior of a liquid storage system under low-gravity conditions, is briefly described. The advantages and disadvantages of middeck payloads compared to other shuttle payload provisions are discussed. A general approach to the integration process is described. The requirements for the shuttle interfaces--such as structures, pressurized systems, materials, instrumentation, and electrical power--are defined and the approach that was used to satisfy these requirements is presented. Currently the middeck experiment is being used as a test bed for the development of various space fluid system components.
A description of AOIPS/2, an interactive hardware and software system to process, integrate, and display meteorological data is presented. The AOIPS/2 objectives and functional specifications are given. The hardware system architecture and work stations and the software architecture and special features are described. A summary is given of the software system and its main menu.
Relaxation labelling is a mathematical technique frequently applied in image processing algorithms. In particular, it is extensively used for the purpose of segmenting images. The paper presents a hardware implementation of a segmentation algorithm, for images consisting of two regions, based on relaxation labelling. The algorithm determines, for each pixel, the probability that it should be labelled as belonging to a particular region, for all regions in the image. The label probabilities (labellings) of every pixel are iteratively updated, based on those of the pixel's neighbors, until they converge. The pixel is then assigned to the region correspondent to the maximum label probability. The system consists of a control unit and of a pipeline of segmentation stages. Each segmentation stage emulates in the hardware an iteration of the relaxation algorithm. The design of the segmentation stage is based on commercially available digital signal processing integrated circuits. Multiple iterations are accomplished by stringing stages together or by looping the output of a stage, or string of stages, to its input. The system interfaces with a generic host computer. Given the modularity of the architecture, performance can be enhanced by merely adding segmentation stages.
The data requirements of mission critical defense systems have been increasing dramatically. Command and control, intelligence, logistics, and even weapons systems are being required to integrate, process, and share ever increasing volumes of information. To meet this need, systems are now being specified that incorporate data base management subsystems for handling storage and retrieval of information. It is expected that a large number of the next generation of mission critical systems will contain embedded data base management systems. Since the use of Ada has been mandated for most of these systems, it is important to address the issues of providing data base management capabilities that can be closely coupled with Ada. A comprehensive distributed data base management project has been investigated. The key deliverables of this project are three closely related prototype systems implemented in Ada. These three systems are discussed.
EnviroNET is an operational system available to the Strategic Defense Initiative (SDI) experimenters who have access to a terminal or dial-up port. It is a tail node on Space Physics Analysis Network (SPAN) accessible directly or through the national networks via NPSS. Some of the benefits to using EnviroNET include: validated NASA environmental information and interactive space models; facilitating the payload integration process; easy access to expert assistance; and potential for time and cost savings.
The Management Integration Panel of the Space Station Operations Task Force was chartered to provide a structure and ground rules for integrating the efforts of the other three panels and to address a number of cross cutting issues that affect all areas of space station operations. Issues addressed include operations concept implementation, alternatives development and integration process, strategic policy issues and options, and program management emphasis areas.
A system composed of several interconnected elastic components that may experience large angular motion relative to each other during operation is referred to as a flexible multibody structure. Several formulations were proposed for the determination of the dynamic response of controlled flexible multibody structures. In general, these formulations consist of superposing elastic deformations of the component body onto the large rigid body motion of the component. It was shown that this particular methodology for combining linear structural deformations with nonlinear kinematics can lead to erroneous response predictions when either the beam member is very flexible or the rotational speed is high. In addition, previous formulations introduce constraint equations to define the interrelations among system components. This approach increases the number of equations that must be solved, and may result in contraint violation when numerical error accumulates during the integration process. In order to overcome the difficulties, a new approach was suggested. The approach is essentially a finite element formulation which takes advantage of the fact that many multibody structures are joint dominated. The Large Angle Transient Dynamic Analysis (LATDYN) program for clarity of documentation, ease of use, user friendliness, modeling generality, and accuracy of results was evaluated. This required gaining a working familiarity with the code and performing several case studies.
The growth of computational power has fueled attempts to automate more of the human role in complex problem solving domains, especially those where system faults have high consequences and where periods of high workload may saturate the performance capacity of human operators. Examples of these domains include flightdecks, space stations, air traffic control, nuclear power operation, ground satellite control rooms, and surgical operating rooms. Automation efforts may have unanticipated effects on human performance, particularly if they increase the workload at peak workload times or change the practitioners' strategies for coping with workload. Smooth and effective changes in automation requires detailed understanding of the congnitive tasks confronting the user: it has been called user centered automation. The introduction of a new computerized technology in a group of hospital operating rooms used for heart surgery was observed. The study revealed how automation, especially 'clumsy automation', effects practitioner work patterns and suggest that clumsy automation constrains users in specific and significant ways. Users tailor both the new system and their tasks in order to accommodate the needs of process and production. The study of this tailoring may prove a powerful tool for exposing previously hidden patterns of user data processing, integration, and decision making which may, in turn, be useful in the design of more effective human-machine systems.
On April 5, 1990, after release from a B-52 aircraft at 43,198 ft, the three-stage Pegasus solid-propellant rocket successfully completed its maiden flight by injecting its 423-lb payload into a 273 x 370-nmi 94-deg-inclination orbit. The first flight successfully achieved all mission objectives, validating Pegasus's unique air-launched concept, the vehicle's design, and its straightforward ground processing, integration and test methods.