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We have developed two modules for use in computer-aided design (CAD) of crewstation environments that enhance the designer's appreciation of factors influencing the pilot's vision and visual processing capacity. The Binocular Optics Module (BOM) is an interactive tool for visualizing geometric aspects of 1) how retinal imagery of the environment changes on the pilot's retinas under conditions of eye and object motion, and 2) how visual capabilities that can be modeled as regions or contours on the retinas, affect spatial perception of the environment. The Visual Performance Module (VPM) contains a signal processing model of human visual discrimination that quantitatively predicts visual discrimination performance. The outputs of the VPM are retinal contours that represent performance probabilities. These contours may be used as inputs to the BOM for visualizing those volumes of space within the crewstation that bound different levels of the pilot's of visual discrimination capability.

Failure analysis of engineering systems typically emphasizes identification and mitigation under an independent failure assumption with dependent failures treated as the exception rather than the rule. Some frameworks for addressing dependent failures through analysis appear in standards including NUREG 0492, ISO 26262, MIL-1629-A, and ARP4761 amongst others. The purpose of identifying these dependencies is to allow system analysts to determine and quantify the factors that influence dependent fault probabilities. Once identified, failure relationships can be incorporated into a Discrete Event Simulation (DES) of the system, providing a mathematically rigorous estimate of system utility (e.g., availability, reliability). The output of a simulation can provide an expected value of performance but additionally, can also allow the analyst to identify the downstream impact of probabilistic dependencies between system elements.

A Computer Applications Laboratory (CAL) has been established at Grumman that is primarily concerned with the visualization of large sets of scientific data. The laboratory is a color graphics workstation environment and communications facility that allows scientists and engineers to quickly process and visualize large quantities of discrete data generated by an experiment or by a supercomputer numerical simulation. The graphical visualization capabilities are supported by in-house research into software development tailored to specific workstation hardware graphics. The CAL facility also serves as a site to the Numerical Aerodynamic Simulation (NAS) facility at NASA's Ames Research Center (ARC) allowing scientists, whose computer requirements involve massive physical memory, to access the CRAY-2.

To make speech recognition a viable input modality in the cockpit, we propose to include visual speech input to improve robustness of the approach in the presence of noise. The visual speech interface includes a headmounted lip imaging apparatus and algorithms to recognize spoken words visually. Our algorithms are based on a few components which address all issues related to lip localization, lip shape model extraction, tracking, feature extraction and recognition. We demonstrate the practicability of the concept with a visual speech recognizer for a discrete-word recognition task that is relatively simple but achievable in real time.

As part of an ongoing collaborative research project between The University of Nottingham and Bombardier Aerospace a pair of end-effectors have been developed that allow solid riveting of aircraft fuselage panels to be performed using conventional robots. This paper describes the development and performance testing of a compact process monitoring system and its integration into the riveting end-effector and testing. The developed process monitoring system is based around a miniature CCD camera combined with a novel structured lighting system. The combination of the structured lighting system with image processing techniques means that good quality images of the drilled and countersunk holes and rivets can be obtained despite the confined environment and highly reflective materials involved. The impact of the system on the overall cycle time is also minimised.

The solution to the problem of establishing the value of the maximum stress in a uniform cylinder with fixed ends, subjected to a unit step change in pressure is presented. It is shown that the ratio of the maximum transient stress to the steady-state stress is a monotonically decreasing function of the damping ratio of the shell. The stress ratio approaches a value of 2 as the damping ratio and the parameter ψ, defined as

In cooperation with the major propulsion engine manufacturers, the authors are developing and demonstrating a unique very high frequency (VHF) vibration monitoring system that integrates various vibro-acoustic data with intelligent feature extraction and fault isolation algorithms to effectively assess engine gearbox and generator health. The system is capable of reporting on the early detection and progression of faults by utilizing piezoelectric, optical, and acoustic frequency measurements for improved, incipient anomaly detection. These gas turbine engine vibration monitoring technologies will address existing operation and maintenance goals for current military system and prognostics health management algorithms for advanced engines.

In the field of the Meteosat Second Generation program, the deep cold space had to be simulated at CSL. The two main constraints were first to keep a temperature lower than 20 [K] under 50 [W] heat load, or lower than 50 [K] under 300 [W] heat load, and secondly, to provide a total hemispherical emittance better than 0.95. Several different coatings have been measured from 5 to 90 [K]. After coating selection, to increase the emittance, the geometrical factor has been adapted. The result is a large opened honeycomb panel, black coated, cooled down by a Helium refrigerator, and with an emittance better than 0.98. Such a panel of 1.6 [m] diameter had to be fitted to the passive cooler of the MSG satellite SEVIRI experiment with a gap of 3 [mm] maximum. As it is used close to infrared optics, special care had also been taken to fit the cleanliness standard class 100, and to avoid degradation after more than twenty thermal cycles from 300 to 5 [K].

Landing of spacecraft on Lunar or Martian surfaces is the last and critical step in inter planetary space missions. The atmosphere on earth is thick enough to slow down the craft but Moon or Mars does not provide a similar atmosphere. Moreover, other factors such as lunar dust, availability of precise onboard navigational aids etc would impact decision making. Soft landing meaning controlling the velocity of the craft from over 6000km/h to zero. If the craft’s velocity is not controlled, it might crash. Various onboard sensors and onboard computing power play a critical role in estimating and hence controlling the velocity, in the absence of GPS-like navigational aids. In this paper, an attempt is made using visual onboard sensor to estimate the velocity of the object. The precise estimation of an object's velocity is a vital component in the trajectory planning of space vehicles, particularly those designed for descent onto lunar or Martian terrains, such as orbiters or landers.

WHILE the centrifugal supercharger is excellently suited to aviation service and to relatively constant-speed, diesel-engine service, Mr. Pigott states, it is not of value for cases of considerable variation in speed where full boost is required at all speeds. The Roots-type blower, the author says further, has had a justified development for low-pressure boost, but is not valuable for compression ratios much in excess of 1.6 because it has no adiabatic compression. The vane-type supercharger, while it has an adiabatic compression, as so far developed appears to the author to be somewhat complex in structure, requires internal lubrication, and has not yet shown satisfactory efficiency compared to other types. The Elliott-Lysholm screw-type and the new P. L. internal-gear type appear to him, however, to give great promise for satisfactory supercharging at the higher pressures beyond the range of the Roots type, and appear to be the best present line of development.

The development of exhaust nozzles and their application in operational military aircraft are discussed. Prime consideration is given to installation factors such as engine bay and nozzle cooling, inlet-engine flow matching, and aerodynamic effects on external afterbody drag. Examples of various operational exhaust systems are given which show how the aircraft-exhaust nozzle characteristics are integrated to achieve maximum system compatibility and performance. Results from one flight test program are presented which show how an aircraft-exhaust nozzle system was integrated to achieve maximum installed performance.

This paper traces the historical development of the BICERI variable compression ratio piston and its use in a number of engines. In early petrol experiments a variable compression piston covering the range from 6.5:1 to 16.5:1 showed significant efficiency improvements on 70 octane petrol. In the diesel engine field, Teledyne Continental increased the power of a V12 direct injection tank engine from 550 hp (30 hp per litre) to 1475hp (80 hp per litre) retaining the original crankcase and structure. At BICERI the output of a supercharged research engine was increased to 40 bar bmep with a peak cylinder pressure of only 165 bar. Military application lapsed with the preference for gas turbine engines, but the time is now right to explore the capabilities of variable compression within the wider automotive scene. Volkswagen have been working on a variable compression engine and have shown fuel consumption improvements up to 13% together with lower emissions.

Gasoline Compression Ignition (GCI) has been identified as a technology which could give both high efficiency and relatively low engine-out emissions. The introduction of any new vehicle technology requires widespread availability of appropriate fuels. It would be ideal therefore if GCI vehicles were able to operate using the standard grade of gasoline that is available at the pump. However, in spite of recent progress, operation at idle and low loads still remains a formidable challenge, given the relatively low autoignition reactivity of conventional gasoline at these conditions. One conceivable solution would be to use both diesel and gasoline, either in separate tanks or blended as a single fuel (“dieseline”). However, with this latter option, a major concern for dieseline would be whether a flammable mixture could exist in the vapour space in the fuel tank.

The Enhanced Thematic Mapper Plus (ETM+) Main Electronics Module (MEM) power supply heat sink temperature is critical to the Landsat-7 mission. It is strongly dependent on the thermal louver design. A lower power supply heat sink temperature increases the reliability of the MEM, and reduces the risk of over heating and thermal shutdown. After the power supply failures in ETM+ instrument thermal vacuum tests #1 and #2, the author performed detailed thermal analyses of the MEM, and proposed to reduce the louver set points by 7°C. At the 1998 Intersociety Energy Conversion Engineering Conference (IECEC), the author presented a paper that included results of thermal analysis of the MEM. It showed that a 7°C reduction of the louver set points could reduce the maximum power supply heat sink temperature in thermal vacuum test and in flight to below 20°C in the cooler outgas mode and in the nominal imaging mode, and has no significant impact on the standby heater duty cycle [1].

3D-scanning is an established method for the documentation of wing ice accretion. The generated 3D-data can be used to determine specific parameters of interest, like the local ice-thickness, or the surface ice roughness. The surface roughness has significant impact on the heat transfer, and therefore on the icing process itself. Insights into the effects of surface roughness on the ice accretion and the correlated aerodynamical effects contribute to the improvement of icing codes. In this paper, the surface roughness of various test specimens is determined by performing a self-organizing maps (SOM) approach for roughness point cloud analysis on data generated with a 3D-scanner. A validation of the SOM method is achieved by means of focus variation microscopy and a mathematical proof of the utilized SOM algorithm. Different scanning systems from several manufacturers are used to determine the surface of different sandpapers.

Hundreds of flight simulation experts from aerospace organizations worldwide – including airframe manufacturers, training device manufacturers (TDM), airlines, operators, and suppliers – will convene at RSi Visual Systems in Coppell, Texas, in September for the 2018 Flight Simulator Engineering and Maintenance Conference (FSEMC). Virtual reality (VR), motion cueing, ADS-B, pilot training for NextGen and SESAR, flight simulation training device (FSTD) technology insertion, and the pros and cons of commercial off-the-shelf (COTS) components top the list of discussion points for the annual conference.

Two aerodynamic concepts proposed for alleviating high-alpha tail buffet characteristics of a LEX (Leading Edge Extension) vortex dominated twin-tail fighter configuration were explored in low-speed tunnel tests on generic models via flow visualizations, 6-component balance measurements and monitoring of tail dynamics. Passive dorsal-fin extensions of the vertical tails, and an active LEX arrangement with up-deflected edge sections were evaluated as independent means of re-structuring the adverse vortical flow environment in the tail region. Each of these techniques successfully reduced the buffet as measured by the root-mean-square of tail accelerometer output, particularly at post-stall angles of attack when the baseline configuration was characterized by high buffet intensity. Used in combination, the two concepts indicated significant tail buffet relief with relatively minor impact on the high-alpha configuration aerodynamics.

For a high speed Diesel engine , gas oil and lighter heavy oil are used in general, but, in order to reduce NOx (Nitorogine Oxide) in exhaust gas and also to prepare for the future world wide oil shortages, blends of alternative fuels, such as alcohols are of interest. These additive to Diesel engines have been studied for a long time in this institute, as well as in many other institutes in JAPAN. Here, the ignition temperature of blended gas oil and others, mixed with various alcohols (mainly ethanol) and Decanol or Isoamyl Ether, are measured independently to analyse the effect of this blending on the improvement of emission quality. Ethanol is of paticular interest because it is a fuel produced from all biomass including cereals, rice, corn, potatoes etc, crops widely produced in many places in the world, as seen in Figure 1.

This SAE Aerospace Information Report (AIR) covers, and is restricted to, selecting appropriate applications for electric powered ground support equipment (GSE) at airports.

The Peripheral Vision Horizon Display (PVHD) uses a laser to project a line parallel to the horizon on the instrument panel. This device, conceived by Dr. Richard Malcolm, reinforces spatial orientation subconsciously through peripheral vision. At first, pilots find the display distracting. Eventually, pilots learn to ignore the line, but the subconscious orienting effect remains. Display interpretation is more natural in roll than in pitch. Provisions for preventing disorientation through peripheral vision inputs should be considered for future aircraft. Other devices, such as a wide field of view HUD, may display peripheral cues more effectively.