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This paper suggests an approach to automatic software design in the domain of graphical user interfaces. There are still some drawbacks in existing user interface management systems (UIMS's) which basically offer only quantitative layout specifications via direct manipulation. Our approach suggests a convenient way to get a default graphical user interface which may be customized and redesigned easily in further prototyping cycles.
This document is a preliminary design of a High Speed Civil Transport (HSCT) named the RTJ-303. It is a 300 passenger, Mach 1.6 transport with a range of 5000 nautical miles. It features four mixed-flow turbofan engines, variable geometry oblique wing, with conventional tail-aft control surfaces. The preliminary cost analysis for a production of 300 aircraft shows that flyaway cost would be 183 million dollars (1992) per aircraft. The aircraft uses standard jet fuel and requires no special materials to handle aerodynamic heating in flight because the stagnation temperatures are approximately 130 degrees Fahrenheit in the supersonic cruise condition. It should be stressed that this aircraft could be built with today's technology and does not rely on vague and uncertain assumptions of technology advances. Included in this report are sections discussing the details of the preliminary design sequence including the mission to be performed, operational and performance constraints, the aircraft configuration and the tradeoffs of the final choice, wing design, a detailed fuselage design, empennage design, sizing of tail geometry, and selection of control surfaces, a discussion on propulsion system/inlet choice and their position on the aircraft, landing gear design including a look at tire selection, tip-over criterion, pavement loading, and retraction kinematics, structures design including load determination, and materials selection, aircraft performance, a look at stability and handling qualities, systems layout including location of key components, operations requirements maintenance characteristics, a preliminary cost analysis, and conclusions made regarding the design, and recommendations for further study.
The Control-Structure Interaction Demonstration Experiment (C-SIDE) is sponsored by the Electro-Optics and Cryogenics Division of Ball Aerospace Systems Group. Our objective is to demonstrate methods of solution to structure control problems utilizing currently available hardware in a system that is an extension of our corporate experience. The larger space structures with which Ball has been associated are the SEASAT radar antenna, Shuttle Imaging Radar (SIR) -A, -B and -C antennas and the Radarsat spacecraft. The motivation for the C-SIDE configuration is to show that integration of active figure control in the radar's system-level design can relieve antenna mechanical design constraints. This presentation is primarily an introduction to the C-SIDE testbed. Its physical and functional layouts, and major components are described. The sensor is of special interest as it enables direct surface figure measurements from a remote location. The Remote Attitude Measurement System (RAMS) makes high-rate, unobtrusive measurements of many locations, several of which may be collocated easily with actuators. The control processor is a 386/25 executing a reduced order model-based algorithm with provision for residual mode filters to compensate for structure interaction. The actuators for the ground demonstration are non-contacting, linear force devices. Results presented illustrate some basic characteristics of control-structure interaction with this hardware. The testbed will be used for evaluation of current technologies and for research in several areas. A brief indication of the evolution of the C-SIDE is given at the conclusion.
Many types of paper documentation are employed on the flight-deck. They range from a simple checklist card to a bulky Aircraft Flight Manual (AFM). Some of these documentations have typographical and graphical deficiencies; yet, many cockpit tasks such as conducting checklists, way-point entry, limitations and performance calculations, and many more, require the use of these documents. Moreover, during emergency and abnormal situations, the flight crews' effectiveness in combating the situation is highly dependent on such documentation; accessing and reading procedures has a significant impact on flight safety. Although flight-deck documentation are an important (and sometimes critical) form of display in the modern cockpit, there is a dearth of information on how to effectively design these displays. The object of this report is to provide a summary of the available literature regarding the design and typographical aspects of printed matter. The report attempts 'to bridge' the gap between basic research about typography, and the kind of information needed by designers of flight-deck documentation. The report focuses on typographical factors such as type-faces, character height, use of lower- and upper-case characters, line length, and spacing. Some graphical aspects such as layout, color coding, fonts, and character contrast are also discussed. In addition, several aspects of cockpit reading conditions such as glare, angular alignment, and paper quality are addressed. Finally, a list of recommendations for the graphical design of flight-deck documentation is provided.
This document describes the instrumentation, operational theory, circuit implementation, calibration procedures, and general notes for the CIRSSE general purpose pneumatic hand. The mechanical design and the control software are discussed. The circuit design, PCB layout, hand instrumentation, and controller construction described in detail in this document are the result of a senior project.
This report develops and applies an aeroacoustic diffraction theory for a duct, or cowl, placed around modelled sources of propeller noise. The regime of flight speed is high subsonic. The modelled cowl's inner wall contains a liner with axially variable properties. Its exterior is rigid. The analysis replaces both sides with an unsteady lifting surface coupled to a dynamic thickness problem. The resulting pair of aeroacoustic governing equations for a lined 'ring wing' is valid both for a passive and for an active liner. Their numerical solution yields the effective dipole and monopole distributions of the shrouding system and thereby determines the cowl-diffracted component of the total radiated field. The sample calculations here include a preliminary parametric search for that liner layout which maximizes the cowl's shielding effectiveness. The main conclusion of the study is that a short cowl, passively lined, should provide moderate reductions in propeller noise.
Kapton polyimide wiring insulation was found to be vulnerable to pyrolization, arc tracking, and flashover when momentary short-circuit arcs have occurred on aircraft power systems. Short-circuit arcs between wire pairs can pyrolize the polyimide resulting in a conductive char between conductors that may sustain the arc (arc tracking). Furthermore, the arc tracking may spread (flashover) to other wire pairs within a wire bundle. Polyimide Kapton will also be used as the insulating material for the flexible current carrier (FCC) of Space Station Freedom (SSF). The FCC, with conductors in a planar type geometric layout as opposed to bundles, is known to sustain arc tracking at proposed SSF power levels. Tests were conducted in a vacuum bell jar that was designed to conduct polyimide pyrolysis, arc tracking, and flashover studies on samples of SSF's FCC. Test results will be reported concerning the minimal power level needed to sustain arc tracking and the FCC susceptibility to flashover. Results of the FCC arc tracking tests indicate that only 22 volt amps were necessary to sustain arc tracking (proposed SSF power level is 400 watts). FCC flashover studies indicate that the flashover event is highly unlikely.
Living and working on the lunar surface will be difficult. Design of habitats, machines, tools, and operational scenarios in order to allow maximum flexibility in human activity will require paying attention to certain constraints imposed by conditions at the surface and the characteristics of lunar material. Primary design drivers for habitat, crew health and safety, and crew equipment are: ionizing radiation, the meteoroid flux, and the thermal environment. Secondary constraints for engineering derive from: the physical and chemical properties of lunar surface materials, rock distributions and regolith thicknesses, topography, electromagnetic properties, and seismicity. Protection from ionizing radiation is essential for crew health and safety. The total dose acquired by a crew member will be the sum of the dose acquired during EVA time (when shielding will be least) plus the dose acquired during time spent in the habitat (when shielding will be maximum). Minimizing the dose acquired in the habitat extends the time allowable for EVA's before a dose limit is reached. Habitat shielding is enabling, and higher precision in predicting secondary fluxes produced in shielding material would be desirable. Means for minimizing dose during a solar flare event while on extended EVA will be essential. Early warning of the onset of flare activity (at least a half-hour is feasible) will dictate the time available to take mitigating steps. Warning capability affects design of rovers (or rover tools) and site layout. Uncertainty in solar flare timing is a design constraint that points to the need for quickly accessible or constructible safe havens.
Graphics displays can be of significant aid in accomplishing a teleoperation task throughout all three phases of off-line task analysis and planning, operator training, and online operation. In the first phase, graphics displays provide substantial aid to investigate work cell layout, motion planning with collision detection and with possible redundancy resolution, and planning for camera views. In the second phase, graphics displays can serve as very useful tools for introductory training of operators before training them on actual hardware. In the third phase, graphics displays can be used for previewing planned motions and monitoring actual motions in any desired viewing angle, or, when communication time delay prevails, for providing predictive graphics overlay on the actual camera view of the remote site to show the non-time-delayed consequences of commanded motions in real time. This paper addresses potential space applications of graphics displays in all three operational phases of advanced teleoperation. Possible applications are illustrated with techniques developed and demonstrated in the Advanced Teleoperation Laboratory at JPL. The examples described include task analysis and planning of a simulated Solar Maximum Satellite Repair task, a novel force-reflecting teleoperation simulator for operator training, and preview and predictive displays for on-line operations.
The objective of this effort is to produce a vehicle layout for the civil tiltrotor wing and center fuselage in sufficient detail to obtain aerodynamic and inertia loads for determining member sizing. This report addresses the parametric configuration and loads definition for a 40 passenger civil tilt rotor transport. A preliminary (point) design is developed for the tiltrotor wing box and center fuselage. This summary report provides all design details used in the pre-design; provides adequate detail to allow a preliminary design finite element model to be developed; and contains guidelines for dynamic constraints.
A conceptual aircraft design study was recently completed which compared three supersonic multimission tactical aircraft. The aircraft were evaluated in two technology timeframes and were sized with consistent methods and technology assumptions so that the aircraft could be compared in operational utility or cost analysis trends. The three aircraft are a carrier-based Fighter/Attack aircraft, a land-based Multirole Fighter, and a Short Takeoff/Vertical Landing (STOVL) aircraft. This paper describes the design study ground rules used and the aircraft designed. The aircraft descriptions include weights, dimensions and layout, design mission and maneuver performance, and fallout mission performance. The effect of changing technology and mission requirements on the STOVL aircraft and the impact of aircraft navalization are discussed. Also discussed are the effects on the STOVL aircraft of both Thrust/Weight required in hover and design mission radius.
A conceptual aircraft design study was recently completed evaluating carrier-based, subsonic attack aircraft using contemporary and future technology assumptions. The study examined a configuration matrix that was made up of light and medium bomb loads, one and two man crews, internal and external weapons carriage, as well as conventional and flying wing planforms. Use of common technology assumptions, engine cycle simulation code, design mission, and consistent application of methods allow for direct comparison of the aircraft. This paper describes the design study ground rules and the aircraft designed. The aircraft descriptions include weights, dimensions, layout, design mission, design constraints, maneuver performance, and fallout mission performance. The strengths, and weaknesses of each aircraft are highlighted.
Design dependencies of antennas in geostationary earth orbits are evaluated, and the tradeoffs between the optical geoscientific goals and achievable architecture capabilities are surveyed. The radial and tangential resolutions are investigated to ascertain whether mission objectives of the antennas may be satisfied. The effects of off-nadir scanning are examined to determine the limits of scan based on realizable resolution. Formulas for raster and spiral scanning time are reviewed and examined to find necessary accelerations. The resulting knowledge is used to evaluate two possible layouts. Torques necessary for slewing these configurations are calculated. A number of rotatory actuators are reviewed to evaluate future design goals for on-board momentum compensation.
The Photovoltaic Array Space Power Plus Diagnostics flight experiment (PASP+) subsumes twelve solar array modules which represent the state of the art in the space photovoltaic array industry. Each of the twelve modules individually feature specific photovoltaic technologies such as advanced semiconductor materials, multi-bandgap structures, lightweight array designs, advanced interconnect technologies, or concentrator array designs. This paper will describe each module in detail including the configuration, components, materials, anticipated on orbit performance, and some of the aspects of each array technology. The layout of each module and the photovoltaic cells or array cross section will be presented graphically. A discussion on the environmental constraints and materials selection will be included as well as a delineation of the differences between the modules and the baseline array configuration in its intended application.
A pinned photodiode/interline CCD Detector Array is under development for the EOS/MODIS-T project. Outstanding features of the device include large pixels, spectrally optimized fill factors, and blooming protection. The detector has 30 spatial rows and 32 spectral columns. The device layout is split into two halves; each half has its own detector area, storage area, and output structure.
Special device modeling, design and layout, and precision processing controls were employed to fabricate new balanced-bridge 2x2 and 4x4 switches on X-cut, Y-propagation LiNbO3 substrate using Ti indiffused optical waveguides. The best of these devices achieved extinction ratio and crosstalk isolation of better than 93 dB electrically (46.5 dB optically). The new switches demonstrate good reproducibility with electrical crosstalk less than -80 dB.
Mission requirements for the EOS-AM Spacecraft intended to monitor global changes of the entire earth system are considered. The spacecraft is based on an instrument set containing the Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER), Clouds and Earth's Radiant Energy System (CERES), Multiangle Imaging Spectro-Radiometer (MISR), Moderate-Resolution Imaging Spectrometer (MODIS), and Measurements of Pollution in the Troposphere (MOPITT). Emphasis is placed on the design, analysis, development, and verification plans for the unique EOS-AM Thermal Control Subsystem (TCS) aimed at providing the required environments for all the onboard equipment in a densely packed layout. The TCS design maximizes the use of proven thermal design techniques and materials, in conjunction with a capillary pumped two-phase heat transport system for instrument thermal control.
A study was performed to develop a fluid system design and show the feasibility of constructing an integrated modular engine (IME) configuration, using an expander cycle engine. The primary design goal of the IME configuration was to improve the propulsion system reliability. The IME fluid system was designed as a single fault tolerant system, while minimizing the required fluid components. This study addresses the design of the high pressure manifolds, turbopumps and thrust chambers for the IME configuration. A physical layout drawing was made, which located each of the fluid system components, manifolds and thrust chambers. Finally, a comparison was made between the fluid system designs of an IME system and a non-network (clustered) engine system.