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1982-02-01
Technical Paper
821408
Donald DeMyer
Pilots have always needed a way to relate their aircraft state to the real world: “Where am I”? “Where am I going”? “How do I get there”? The translational media has been “paper maps” showing earth coordinates and various projection types with mission significant features such as NAV Aids, terrain information, and cultural details. In todays dynamic cockpit environment, the reading of a latitude-longitude display and finding that position on a map is not conducive to rapid “situational awareness”. One answer is an electronic, graphic display of map information relative to the aircraft. The work was done under the sponsorship of the Air Force Flight Dynamics Laboratory to demonstrate the basic feasibility of the Digital Moving Map Display for the modern cockpit. Within the effort, the effect of color, declutter, scaling (zoom), map orientation (north-up and track-up), and the quantification of digital storage and processing requirements has been evaluated.
1982-02-01
Technical Paper
821422
Hussein M. Youssef
The use of digital computers in flight control and avionics systems requires new techniques to verify and validate (V&V) the associated applications software. To compound the problem, changes in the application software subsequent to final certifications may require repeated certification testing, an expensive and time consuming process. Digital computer technology created the difficult validation problem; but it can also solve it through application of advances in design and validation technology such as Finite State Machine (FSM), Logic Tree Graphic (LTG), and Robotic Testing (RT). With FSM, system design is described in precise manner that allows direct testing of design states. The LTG will allow the design of test cases using minimal cut sets for failure combinations. In RT, the control of the test program, the detailed magnitude of the test, as well as the sequence of the test is exact and can be repeated in the same exact manner.
1982-02-01
Technical Paper
821419
W. L. Swingle, J. T. Edge
The current design base of the Space Shuttle Orbiter employs hydraulic actuation for control of aerosurfaces, engine thrust, engine thrust vector, brakes, and landing gear functions. As early as 1972, electromechanical actuation (EMA) was considered as an alternative system. As a result of continued advances in technology development, studies now indicate that EMA is a more attractive alternative. Major advantages are weight reduction, striking improvement in energy efficiency, easier maintenance, and a cleaner vehicle. The results of a system study advocating EMA for the Orbiter are presented. Emphasis is placed on a clear understanding of the relationships between mission requirements and design parameters. EMA system energy requirements are compared with those of the existing hydraulic system. Detailed discussion of the synthesized EMA system is limited to the aerosurface actuators. The design is consistent with the Orbiter “fail operational,” “fail safe” redundancy requirement.
1982-02-01
Technical Paper
821386
James R. Gannett
This paper addresses the question of whether automation is being used in the proper applications in aircraft in order to maximize aircraft capabilities and make the most of human performance capacity. It is believed that the aircraft designers, while employing automation, have given due regard to the pilot's role as operator and manager of the aircraft. There does, however, seem to be valid concern for the human element in certain aspects of the air traffic control system.
1982-02-01
Technical Paper
821399
Robert J. Baumbick
Abstract Because of optics' inherent immunity to electromagnetic noise it offers considerable promise in improving the reliability of propulsion control systems. Future engine systems will be electronically controlled with no hydromechanical backup. The electronic computer will have to be isolated from electromagnetic noise by heavy shielding of metallic transmission lines. Fiberoptic data transmission and passive optical sensors can insure more complete isolation of the computer from electromagnetic disturbances and thereby produce a more reliable control system. This paper discusses work being done by NASA Lewis Research Center in the area of optical sensors and optically controlled actuators for use in airbreathing engine control systems. The environmental conditions in which the aircraft will operate, require the fiberoptic cables and optical connectors to perform reliably at temperatures over the −55°C to 260°C range.
1982-02-01
Technical Paper
821430
Gerald L. Thompson, Thomas J. Philumalee
The National Airspace System Plan delineates specific improvements for facilities and equipments which must be made in order to meet the projected demands of air transportation through the year 2000. The plan focuses on how to best accomplish the following objectives: Accommodate spiralling demands for aviation services Constrain costs Recast the required technical framework Deal with aging facilities The primary purpose of the modernization of the airspace system is to reduce operating costs while enhancing safety. This requires: higher levels of automation consolidation of major facilities
1982-02-01
Technical Paper
821435
J. B. Leonard
Electromechanical Actuation Systems (EMAS) using advanced state-of-the-art technology offer significant benefits in primary flight control applications. Fighter and attack aircraft present the greatest challenge, but studies have shown feasibility for those applications. The use of samarium cobalt “inside-out” DC motors, solid-state power switching, and microprocessor control of commutation, current, and frequency are the advances that have made EMAS contenders for military aircraft applications. Benefits include elimination of hydraulic systems, improved logistics, increased reliability, and lower life-cycle costs. The studies addressed actuation of canard and rudder control surfaces on supersonic Navy-fighter aircraft.
1982-02-01
Technical Paper
821434
Cary R. Spitzer, Ray V. Hood
A brief definition of an “All Electric Airplane” will be presented. Several NASA and DOD studies have examined the application of advanced electric/electronic technologies. The benefits identified in these studies will be summarized. The state-of-the-art in all electric airplane technology will be described. A NASA program has been proposed to develop the necessary technology base for industry application. The elements of this proposed program will be discussed.
1982-02-01
Technical Paper
821451
James J. Treacy
1982-02-01
Technical Paper
821462
W. Glen Smith, Richard J. Fandel
The F-16 main engine inflight restart capability would be greatly enhanced by utilizing a Super Integrated Power Unit (SIPU). Because the available starter power remains constant at all altitudes, the engine can be motored at relatively high rotative speeds, providing for rapid acceleration to a self sustaining condition after relight. This reduced start time plus a multiple start capability, reduces altitude loss and increases safety during combat. The SIPU concept expands the airstart window and allows the pilot to assume a “best range” flight attitude which maximizes both time and range by up to 35% in the event the engine is not able to start.
1982-02-01
Technical Paper
821461
James A. Williams, Armando D. Lucci, Buryl L McFadden
An SIPU is a single aircraft power unit capable of providing (1) electrical, pneumatic, and hydraulic power for ground maintenance and standby operations, (2) normal main engine start power, (3) emergency in-flight electrical and hydraulic power, and (4) in-flight emergency main engine restart power. Power can be obtained from: jet fuel combustion with air for the ground operations and normal engine starts; a gas generator system using on-board stored propellants for the emergency power and emergency engine restart functions; and the aircraft main engine compressor air as a second source for the emergency electrical and hydraulic power function. An SIPU concept demonstration program is currently near completion at Rockwell International's Rocketdyne Division, sponsored by the Aeropropulsion Laboratory at Wright-Patterson Air Force Base. The program is for design, fabrication, assembly, and test of a demonstrator SIPU capable of performing all four functions.
1982-02-01
Technical Paper
821479
John R. Fowler, William F. Davis, Emmet Dancy
Spacecraft sinusoidal vibration test data is analyzed, using overlap processing, to compute transfer functions and to determine frequencies, damping, and modal amplitudes. Results are compared with results obtained from random vibration test data and show excellent agreement. The overlap processing method, therefore, is acceptable for performing system identification computations from typical swept sine vibration test data. Use of alternative reference point for computation of transfer functions is discussed.
1982-02-01
Technical Paper
821496
Antal K. Bejczy
The distribution of control between man and machine is dependent on the tasks, available technology, human performance characteristics and control goals. This dependency has very specific projections on systems designed for teleoperation in space. This paper gives a brief outline of the space-related issues and presents the results of advanced teleoperator research and development at the Jet Propulsion Laboratory (JPL). The research and development work includes smart sensors, flexible computer controls and intelligent man-machine interface devices in the area of visual displays and kinesthetic man-machine coupling in remote control of manipulators. Some of the development results have been tested at the Johnson Space Center (JSC) using the simulated full-scale Space Shuttle Remote Manipulator System (RMS). The research and development work for advanced space teleoperation is far from complete and poses many interdisciplinary challenges.
1982-02-01
Technical Paper
821498
Keith H. Miller
This paper discusses the origin of the command station concepts for the Space Operations Center that Boeing Aerospace Company defined for NASA-Johnson Space Center. This discussion includes the description of the mission scenario used to define command and control requirements and the relevant requirements imposed by NASA. These requirements were analyzed to produce command center configurations and control panel layouts. The types of controls and displays to be used are discussed.
1982-02-01
Technical Paper
821503
James N. Brooks
This paper describes the technology that is presently available to the U.S. Navy to enable it to safely and routinely conduct helicopter approaches to and landings on small moving platforms in near zero-zero weather with 10-foot seas.
1982-02-01
Technical Paper
820449
L. A. Reams, T. A. Wiemero, M. B. Levin, W. R. Wade
The effects of current mechanical fuel control systems on CVS emissions and maximum fueling rate smoke levels of light-duty Diesel engines were investigated. A comparison of emission projections made from steady state mapping data and actual vehicle emission test results indicated that modifications to the transient fueling characteristics had the potential to reduce particulate emissions by over 20%. An experimental Diesel electronic fuel control system was developed and used to assess the effects of fuel control system modifications on Diesel vehicle emissions and smoke levels. Modified governor characteristics were shown to provide a 37% reduction in particulate emissions relative to the baseline min-max governor. Maximum fueling rate calibrations were developed to provide constant smoke levels across the engine speed range.
1982-02-01
Technical Paper
820448
John A. Kimberley, James R. Voss
This paper will outline one new in-line injection pump that is being released to production and the electronic controls that go with this pump and the other pumps that are currently in production. The in-line pump has an internal timing device and is designed to be especially compatible with the timing requirements needed for emission control. With the electronic controls the fuel injection pumps will have many advantages. The electronics will make the pump smooth and easy to use. The flexibility of the electronics will make possible a much better timing strategy which will approach the ideal emissions fuel consumption compromise. The use of the PROM will impact the large inventory of pump specifications and reduce the turnaround time for service.
1982-02-01
Technical Paper
820447
M. U. Trenne, A. P. lves
Consumer expectations of automotive diesel performance combined with stringent emission statutes have accelerated the development of electronically controlled diesel fuel injection systems which provide precise control of the quantity of fuel injected and the timing of injection. A comparison of closed loop and open loop control techniques in this application is presented with closed loop control shown to exhibit superior accuracy, response time and disturbance input rejection characteristics while offering the potential of relaxed actuator specifications.
1982-02-01
Technical Paper
820453
Robert F. Giese, Margaret K. Singh, Martin J. Bernard
This paper analyzes the impact of electric and hybrid vehicle (EHV) charging requirements on electric utilities. The impact for the five EHV scenarios examined generally is small, with total EHV electricity consumption in the HIGH scenarios representing ∿3% of projected U.S. electricity demand in 2000. However, in several areas, EHV electricity consumption in the HIGH scenarios represents a sizable fraction of electricity demand in 2000 and would have to be included in utility planning. Based on 1979 fuel prices, the total marginal cost of electicity (excluding taxes) for off-peak EHV charging ranges from $0.017/kWh (Federal Regions I and X) to $0.051/kWh (Federal Region II).
1982-02-01
Technical Paper
820450
Ludwig Walz
The range of applications for Diesel engines, especially for automotive Diesel engines, is steadily increasing. High fuel costs, increasingly severe emission and fuel consumption regulations together with the driver’s comfort expectations place increasing demands on the fuel injection system. To satisfy these requirements, the engine’s needs must be precisely determined. A suitable fuel injection system can then be defined and its components matched to the engine. The objective of this paper is to illustrate the necessity for a close cooperation between the engine and the fuel injection equipment manufacturer, to describe the application process and to show the fuel injection equipment for automotive Diesel engines.
1982-02-01
Technical Paper
820458
Tomoyoshi Kurashige, Sumio Kobane, Hiroshi Takahashi, Satoru Komatsu
This paper presents an overview of the device which semi permanently supervises low tire pressure of driving or parking car, including low spare tire pressure. Such continual supervision is attained by the application of wireless system. The sensor on the tire has no power supply. It transmits echo radio wave by the excitement of its element, which is originated by the transporting radio signal from the detector on the car body. The device employs fail-safe system and its key components are consisted of passive elements, so that the device provides high reliability.
1982-02-01
Technical Paper
820817
J.M. Wood, M.H. Radley
The paper discusses the development and thinking behind the construction of the T.R.X. sports car which features external body panels in engineering thermoplastics. The advantages of injection moulding as a high quality mass production process ensuring perfect reproducibility and close tolerance fits are stressed. High weight reductions are possible against conventional materials and many examples are given. High speed, high quality production at a rate commensurate with modern car build is possible with technology currently available and in place today. Finally, alternative construction concepts are discussed to meet a wide range of industry requirements for automotive body components.
1982-02-01
Technical Paper
820816
A. D. Nielsen
This paper presents an Electromagnetic Compatibility (EMC) Test Plan and Procedure for automotive electronic components which predicts the EMC performance in a vehicle. Production representative vehicles for EMC evaluation are often not available in sufficient quantities until late in an electronic component design stage where changes are most costly. This Test Plan and Procedure addresses this problem by allowing early detection and definition of component design deficiencies. Also presented are vehicle and electronic component EMC design practices with low cost being a prime consideration. These practices have been proven effective in the most hostile vehicle noise environments on a number of automotive electronic systems.
1982-02-01
Technical Paper
820815
Walter J. Dippold
Recommendations to improve the utilization of currently available battery technology have been made. Use of a thermally controlled environment for the EV propulsion battery, electrolyte stirring, and maintenance time reductions are predicted to make electric vehicles desirable for urban commercial applications.
1982-02-01
Technical Paper
820871
Vincent Cirrito
The thermal design of integrated avionic racks for aircraft installation must be evaluated from a total systems integration vantage point. The thermal design parameters are the drivers that will dictate the maximum allowable module power for reliability and avionic partitioning. Therefore, the objective of the thermal design procedure must be to provide a system configuration with maximum reliability and minimum aircraft penalty and life cycle costs. As part of the Integrated Rack Concept Study in V/STOL Type Aircraft a procedure was developed and applied to module configurations with chip carrier semiconductor devices. The cooling air requirement at the aircraft environmental control system interface was defined as a function of air supply temperature.
1982-02-01
Technical Paper
820844
Bob J. Jackson, David Rogers
The design, fabrication, development testing, and growth potential of an advanced design thermal control subsystem for the free flying P80-2 satellite is described. Free flying satellite applications can have large payload heat rejection requirements. For example, the P80-2 heat rejection requirement was in excess of 4 kilowatts. An inherent requirement for these vehicles is to incorporate a means for transferring heat from a source, frequently electronic components, to a sink, typically a space radiator. This heat transfer can be accomplished by a liquid coolant loop that is pumped and temperature controlled by a coolant pumping and conditioning assembly (CPCA) system. Major CPCA components typically include a long life space qualified pump, power inverter, thermal control valve, accumulator, and miscellaneous sensors.
1982-02-01
Technical Paper
820842
H. B. Warner
A sunshield has been designed that minimizes the heat load on a space telescope that uses cryogenically cooled mirrors. It shades the solar radiation from any direction except for a small solid angle about the line of sight. This design allows great freedom in pointing a cold telescope-like sensor with respect to the sun since it employs a much shorter, smaller and lighter sunshade than that which has been previously available. It requires no external coaling system and does not add significantly to the heat load.
1982-02-01
Technical Paper
820779
Donald J. Dobner, Edward J. Woods
A complete electric vehicle dynamic simulation has been developed for evaluating the performance of drive train components and control strategies. The simulation includes models for the drive motor and its field controller and armature chopper, the battery, a transmission, and a transmission actuator and associated transmission control to accomplish automatic gear changes. These component models along with a vehicle dynamics model provide simulated vehicle performance in response to driver commands. The simulation provides a tool for developing control algorithms, and serves as a basis for examining other electric vehicle problems. The modular structure readily allows adding or substituting component models so that other hardware configurations can be studied.
1982-02-01
Technical Paper
820777
S.J. Sobolak
This paper describes a mathematical model of the Ford Vehicle Speed Control System (Cruise Control). The model consists of component models of the engine, fluid coupling, speed sensor, actuator (pneumatic or electric), and vehicle dynamics. A computer implementation of the model is used to calculate the dynamic response of system variables to a sequence of driver commands, and to a sinusoidal road profile. Example computer solutions are given. The model is useful in evaluating system performance of proposed design innovations, determining performance sensitivity to component parameter values, and serves as a learning tool.
1982-02-01
Technical Paper
820764
P. Beuzit, P. Fontanet, J. Simon
In order to improve the vehicle’s stability in riding, a complete linear mathematical model has been developped for a front wheel drive vehicle. All the suspension and steering effects are taken into account. Two approaches are used: the modal analysis of the vehicle response can be well represented by two modes (exponential and sinusoidal) only and coupling between 3 basical motions: yaw - side-slipping, rolling and steering. The effects of the main characteristics of the vehicle on the responses are studied essentially in the way of damping. This study exhibits the importance of coupling between yawing and rolling. The optimization consists to decrease the importance of the coupling and the rolling as far as possible. In order to do that, a semi-analytical study of the transfer function between yaw velocity and roll angle is performed. This allows to check the best set of suspension’s parameters.
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