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This is part 3 of the conference proceedings on rotorcraft technology. This volume is divided into areas on systems integration, research aircraft, and industry. Representative titles from each area are: system analysis in rotorcraft design, the past decade; rotorcraft flight research with emphasis on rotor systems; and an overview of key technology thrusts at Bell Helicopter Textron.
The purpose of this study is to define the requirements of commercially motivated microgravity combustion experiments and the optimal way for space station to accommodate these requirements. Representatives of commercial organizations, universities and government agencies were contacted. Interest in and needs for microgravity combustion studies are identified for commercial/industrial groups involved in fire safety with terrestrial applications, fire safety with space applications, propulsion and power, industrial burners, or pollution control. From these interests and needs experiments involving: (1) no flow with solid or liquid fuels; (2) homogeneous mixtures of fuel and air; (3) low flow with solid or liquid fuels; (4) low flow with gaseous fuel; (5) high pressure combustion; and (6) special burner systems are described and space station resource requirements for each type of experiment provided. Critical technologies involving the creation of a laboratory environment and methods for combining experimental needs into one experiment in order to obtain effective use of space station are discussed. Diagnostic techniques for monitoring combustion process parameters are identified.
The design and operation of high-power lasers for industrial applications are discussed in reviews and reports. Topics addressed include the status of optical technology in the Netherlands, laser design, the deposition of optical energy, laser diagnostics, nonmetal processing, and energy coupling and plasma formation. Consideration is given to laser-induced damage to materials, fluid and gas flow dynamics, metal processing, and manufacturing. Graphs, diagrams, micrographs, and photographs are provided.
This handbook is intended to provide a ready reference for many of the solid and liquid lubricants used in the space industry. Lubricants and lubricant properties are arranged systematically so that designers, engineers, and maintenance personnel can conveniently locate data needed for their work. This handbook is divided into two major parts (A and B). Part A is a compilation of solid lubricant suppliers information on chemical and physical property of data of more than 250 solid lubricants, bonded solid lubricants, dispersions, and composites. Part B is a compilation of chemical and physical property data of more than 250 liquid lubricants, greases, oils, compounds, and fluids. The listed materials cover a broad spectrum from manufacturing and ground support to hardware applications of spacecraft.
The privatization and commercialization of the expendable launch vehicle (ELV) industry is examined. The government policy to terminate ELV service with the development of the Shuttle is discussed. NASA support to commercial ELVs and privatization and commercialization ELV agreements executed by NASA are considered. The services offered by several companies producing and operating ELVs, and plans for NASA to procure launch services competitively from the private sector are presented.
This document recounts the accomplishments of the 11-year Flat-Plate Solar Array Project, which is recognized as one of the most successful and comprehensive technology-transfer efforts ever achieved through government-sponsored research and development. Few Federal research projects can claim the degree of industry involvement that was a fundamental aspect of the FSA Project. This philosophy in turn led to an extraordinary transfer of technology to the private sector, and assured that a maximum amount of the taxpayers' dollars were devoted to research of primary importance to the technology's commercialization.
An overview is given of a design optimization project that is in progress at the GE Research and Development Center for the past few years. The objective of this project is to develop a methodology and a software system for design automation and optimization of structural/mechanical components and systems. The effort focuses on research and development issues and also on optimization applications that can be related to real-life industrial design problems. The overall technical approach is based on integration of numerical optimization techniques, finite element methods, CAE and software engineering, and artificial intelligence/expert systems (AI/ES) concepts. The role of each of these engineering technologies in the development of a unified design methodology is illustrated. A software system DESIGN-OPT has been developed for both size and shape optimization of structural components subjected to static as well as dynamic loadings. By integrating this software with an automatic mesh generator, a geometric modeler and an attribute specification computer code, a software module SHAPE-OPT has been developed for shape optimization. Details of these software packages together with their applications to some 2- and 3-dimensional design problems are described.
Tasks for two coordinated industrial robots always bring the robots in contact with a same object. The motion coordination among the robots and the object must be maintained all the time. To plan the coordinated tasks, only one robot's motion is planned according to the required motion of the object. The motion of the second robot is to follow the first one as specified by a set of holonomic equality constraints at every time instant. If any modification of the object's motion is needed in real-time, only the first robot's motion has to be modified accordingly in real-time. The modification for the second robot is done implicitly through the constraint conditions. Thus the operation is simplified. If the object is physically removed, the second robot still continually follows the first one through the constraint conditions. If the first robot is maneuvered through either the teach pendant or the keyboard, the second one moves accordingly to form the teleoperation which is linked through the software programming. Obviously, the second robot does not need to duplicate the first robot's motion. The programming of the constraints specifies their relative motions.
Students are introduced to methods and concepts for systematic selection and evaluation of materials which are to be used to manufacture specific products in industry. For this laboratory exercise, students are asked to work in groups to identify and describe a product, then to proceed through the process to select a list of three candidates to make the item from. The exercise draws on knowledge of mechanical, physical, and chemical properties, common materials test techniques, and resource management skills in finding and assessing property data. A very important part of the exercise is the students' introduction to decision making algorithms, and learning how to apply them to a complex decision making process.
The implementation and experimental validation of a new direct adaptive control scheme on a PUMA 560 industrial robot is described. The testbed facility consists of a Unimation PUMA 560 six-jointed robot and controller, and a DEC MicroVAX II computer which hosts the Robot Control C Library software. The control algorithm is implemented on the MicroVAX which acts as a digital controller for the PUMA robot, and the Unimation controller is effectively bypassed and used merely as an I/O device to interface the MicroVAX to the joint motors. The control algorithm for each robot joint consists of an auxiliary signal generated by a constant-gain Proportional plus Integral plus Derivative (PID) controller, and an adaptive position-velocity (PD) feedback controller with adjustable gains. The adaptive independent joint controllers compensate for the inter-joint couplings and achieve accurate trajectory tracking without the need for the complex dynamic model and parameter values of the robot. Extensive experimental results on PUMA joint control are presented to confirm the feasibility of the proposed scheme, in spite of strong interactions between joint motions. Experimental results validate the capabilities of the proposed control scheme. The control scheme is extremely simple and computationally very fast for concurrent processing with high sampling rates.
The implementation and experimental validation of a direct adaptive control scheme on a PUMA 560 industrial robot is discussed. The design theory for direct adaptive control of manipulators is outlined and the test facility and software are described. Results are presented from the experiments on the simultaneous control of all of the six joint angles and control of the end-effector position and orientation of the robot. Also, the possible applications of the direct adaptive control scheme are considered.
A study of industrial liquid sulfur flows at about 130 C yields information on the thermal and rheological characteristics of the sulfur encountered in Io's volcanic activity. As the local sulfur flow cools and/or the local flow rate decreases, the formation of a crust over much of the surface does not prevent a continuation of flow underneath. Subsequent rapid development of a durable crust implies the formation of extensive crusts on Ionian sulfur flows, significantly reducing heat loss and extending flow length. It is suggested on the basis of the present laboratory results that the colors of proposed sulfur flows on Io may correlate with neither the temperature nor the inferred rheological properties attributed to the colors.
Some aspects of research development and production of quantum frequency standards, carried out in QUARTZ Research and Production Association (RPA), Gorky, U.S.S.R., were investigated for the last 25 to 30 years. During this period a number of rubidium and hydrogen frequency standards, based on the active maser, were developed and put into production. The first industrial model of a passive hydrogen maser was designed in the last years. Besides frequency standards for a wide application range, RPA QUARTZ investigates metrological frequency standards--cesium standards with cavity length 1.9 m and hydrogen masers with a flexible storage bulb.
A cooperative commercial development project designed to focus on cost-effective and practical applications of satellite remote sensing in forest management is discussed. The project, initiated in September, 1988 is being executed in three phases: (1) development of a forest resource inventory and geographic information system (GIS) updating systems; (2) testing and evaluation of remote-sensing products against forest industry specifications; and (3) integration of remote-sensing services and products in an operational setting. An advisory group represented by eleven major forest-product companies will provide direct involvement of the target market. The advisory group will focus on the following questions: Does the technology work for them? How can it be packaged to provide the needed forest-management information? Can the products and information be provided in a cost-effective manner?
The application of industry standards to the development of avionics software is discussed, focusing on verification and validation activities. It is pointed out that the procedures that guide the avionics software development and testing process are under increased scrutiny. The DO-178A guidelines, Software Considerations in Airborne Systems and Equipment Certification, are used by the FAA for certifying avionics software. To investigate the effectiveness of the DO-178A guidelines for improving the quality of avionics software, guidance and control software (GCS) is being developed according to the DO-178A development method. It is noted that, due to the extent of the data collection and configuration management procedures, any phase in the life cycle of a GCS implementation can be reconstructed. Hence, a fundamental development and testing platform has been established that is suitable for investigating the adequacy of various software development processes. In particular, the overall effectiveness and efficiency of the development method recommended by the DO-178A guidelines are being closely examined.
Decentralized direct adaptive control scheme for six-jointed industrial robot eliminates part of overall computational burden imposed by centralized controller and degrades performance of robot by reducing sampling rate. Control and controller-adaptation laws based on observed performance of manipulator: no need to model dynamics of robot. Adaptive controllers cope with uncertainties and variations in robot and payload.
The proceedings of the conference are presented. It is proposed that commercial development in space is an important element in the future competitive posture of the industrial nations of the world. The resources and characteristics of space will play a major role in opening a new economic frontier for all the spacefaring nations of the world. Some topics of discussion are as follow: NASA's mission and the role of CCD's; A balanced commercial access to space; Systems for COMET; SPACEHAB; Space Station Freedom; The center for macromolecular crystallography; Center for space power and advanced electronics; and The center for mapping.
In propulsion industry, computational techniques (namely computational fluid dynamics) are gradually becoming engineering design and analysis tools, especially in the case of high performance aircraft engines, high speed air breathing propulsion, rocket propulsion, and advanced nuclear propulsion and electric propulsion. The key issues in acceptance of CFD are turn around time, cost, and accuracy. The turn around time of analysis has to fit program schedules. Cost is still the bottom line, the value of CFD to the program should at least balance its cost. CFD can be used if it can be divided into two major parts: numerics and physical models.