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Technical Paper

“SODART” Telescope Silicon Detector Cooling System (Thermal Test Results of the Scale-Down Model)

1992-07-01
921365
The onboard “SODART” telescope silicon detector cooling system of the “Spectrum-X-Gamma” observatory, which is designed for the space objects X-ray radiation study, is described. The scale-down model of the passive cooling system description and thermal vacuum test results of this model are given. In the real cooling system the minimal detector temperature at 300 mW heat release is expected about 107 K.
Technical Paper

eROSITA Camera Low Temperature Thermal Control

2008-06-29
2008-01-1957
eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is a powerful X-ray telescope under development by the Max-Planck-Institut für extraterrestrische Physik (MPE) in Garching, Germany. eROSITA is the core instrument on the Russian SRG1 mission which is planned for launch in 2011. It comprises seven nested Wolter-I grazing incidence telescopes, each equipped with its own CCD camera. The mirror modules have to be maintained at 20°C while the cameras are operated at -80°C. Both, mirrors and CCDs have to be kept within tight limits. The CCD cooling system consists of passive thermal control components only: two radiators, variable conductance heat pipes (VCHP) and two special thermal storage units. The orbit scenario imposes severe challenges on the thermal control system and also on the attitude control system.
Technical Paper

byteflight~A new protocol for safety-critical applications

2000-06-12
2000-05-0220
The permanently increasing number of convenience and safety functions leads to higher complexity of in-car electronics and the rapidly growing amount of sensors, actuators and electronic control units places higher demands on high- speed data communication protocols. Safety-critical systems need deterministic protocols with fault-tolerant behavior. The need for on-board diagnosis calls for flexible use of bandwidth and an ever-increasing number of functions necessitates a flexible means of extending the system. None of the communication solutions available on the market until now (like CAN or TTP) have been able to fulfill all these demands. To solve these problems, BMW together with several semiconductor companies has developed a new protocol for safety-critical applications in automotive vehicles.
Technical Paper

Zone of Influence of Porous Suction Tubes in Condensing Heat Exchanger for Space Systems

2008-06-29
2008-01-2075
A “next generation” condensing heat exchanger for space systems has to satisfy demanding operational requirements under variable thermal and moisture loads and reduced gravity conditions. Mathematical models described here are used to investigate transient behavior of wetting and de-wetting dynamics in the binary porous system of porous tubes and porous cold plate. The model is based on the Richard's equation simplified for the zero-gravity conditions. The half-saturation distance or the zone of influence of the porous annular suction tubes on the cold-plate porous material will be in the range of 1 to 10 cm for the time scales ranging from 100 to 10,000 seconds and moisture diffusivity in the range of D = 10-4 to 10-6 m2/s.
Technical Paper

You-Are-Here Maps for International Space Station: Approach and Guidelines

2004-07-19
2004-01-2584
Guidelines for designing you-are-here (YAH) maps aboard International Space Station (ISS) are proposed, based on results from previous 3D spatial navigation studies conducted by our research group and colleagues. This paper reviews terrestrial YAH maps, the common errors associated with them, and how to appropriately implement what is known from terrestrial to micro-gravity YAH maps. We conclude with a creative example of an ISS YAH map that utilizes given guidelines and information visualization techniques.
Technical Paper

XMM-NEWTON Thermal Design and In-orbit Performance

2000-07-10
2000-01-2372
The XMM-NEWTON satellite is the ESA X-ray spaceborne observatory covering the soft X-ray portion of the electromagnetic spectrum. XMM-NEWTON has been put in orbit on December, 10th 1999 by an Ariane 5 single launch. The spacecraft has a conventional thermal design that takes full advantage of the stable environment provided by its high altitude/long period orbit and by the limited variation of solar attitude angles in order to provide a stable platform for the telescope system. The precise geometry and alignment of the telescope system impose strict temperature requirements so that not only temperature gradients have to be kept small but also, and more importantly, time-variations of the gradients have to be minimised. In the paper, the thermal behaviour of the spacecraft as verified by its thermal test programme is compared with the early in-orbit temperature measurements.
Technical Paper

X-Ray Computed Tomography for Verification of Rivet Installation Assessment Techniques

1998-09-15
982140
High quality rivet installation is of critical importance to the aerospace industry, and the existence of gaps between the rivet head and the countersink is undesirable. Detection of gaps traditionally involves sectioning through rivet joints. Two concerns exist for this method of evaluation: it provides data only from the sectioned plane, and it has potential to alter the gaps. X-ray computed tomography (CT) was used to validate the effectiveness of the tradition sectioning method. It was revealed that the sectioning process generally increased the size of gaps. CT images also revealed that the gaps are not necessarily uniform around the rivet.
Technical Paper

Workspace Analysis and Visualization for Santos'™ Upper Extremity

2005-06-14
2005-01-2739
Workspace is an important function for human factors analysis and is widely applied in product design, manufacturing, and ergonomics evaluations. This paper presents the workspace analysis and visualization for Santos™ upper extremity, a new virtual human with over 100 DOFs that is highly realistic in terms of appearance, behavior, and movement. Jacobian Rank deficiency method is implemented to determine the singular surfaces. The joint limits are considered in this formulation; three types of singularities are analyzed. This closed-form formulation can be extended to numerous different scenarios such as different percentiles, age groups, or segments of body. A realtime scheme is used to build the workspace library for Santos™ that will study the boundary surfaces off-line and apply them to Santos™ in the virtual environment (Virtools®). To visualize the workspace, we develop a user interface to generate the cross section of the reach envelope with a plane.
Standard

Wire and Cable Marking Process, UV Laser

2018-01-18
WIP
AS5649A
This standard is applicable to the marking of aerospace vehicle electrical wires and cables using ultraviolet (UV) lasers. This standard specifies the process requirements for the implementation of UV laser marking of aerospace electrical wire and cable and fiber optic cable to achieve an acceptable quality mark using equipment designed for UV laser marking of identification codes on aerospace wire and cable. Wiring specified as UV laser markable subject to AS4373 Test Methods for Insulated Electric Wire and which has been marked in accordance with this standard will conform to the requirements of AS50881.
Standard

Wire and Cable Marking Process, UV Laser

2007-05-31
CURRENT
AS5649
This standard is applicable to the marking of aerospace vehicle electrical wires and cables using ultraviolet (UV) lasers. This standard specifies the process requirements for the implementation of UV laser marking of aerospace electrical wire and cable and fiber optic cable to achieve an acceptable quality mark using equipment designed for UV laser marking of identification codes on aerospace wire and cable. Wiring specified as UV laser markable subject to AS4373 Test Methods for Insulated Electric Wire and which has been marked in accordance with this standard will conform to the requirements of AS50881.
Technical Paper

Wind-Tunnel Investigation of the Forebody Aerodynamics of a Vortex-Lift Fighter Configuration at High Angles of Attack

1988-10-01
881419
Results of a recent low-speed wind-tunnel investigation conducted to define the forebody flow on a 16% scale model of the NASA High Angle-of-Attack Research Vehicle (HARV), an F-18 configuration, are presented with analysis. Measurements include force and moment data, oil-flow visualizations, and surface pressure data taken at angles of attack near and above maximum lift (36° to 52°) at a Reynolds number of one million based on mean aerodynamic chord. The results presented identify the key flow-field features on the forebody including the wing-body strake.
Technical Paper

Wind Tunnel Measurements of Simulated Glaciated Cloud Conditions to Evaluate Newly Developed 2D Imaging Probes

2019-06-10
2019-01-1981
Instrumentation that has been used for characterization of mixed-phase and glaciated conditions in the past, like the OAP probes, are subject to errors caused by variations in diffraction on the images away from the object plane and by the discrete nature of their particle detection and sizing. Correction methods are necessary to consider their measurements adequate for high ice water content (IWC) environments judged to represent a significant safety hazard to propellers and turbofan engine operability and performance. For this reason, within the frame of EU FP7 HAIC project, instrumentation characterization and validation is considered a major element need for successful execution of flight tests campaigns. Clearly, instrumentation must be sufficiently reliable to assess the reproducibility of artificial clouds with high ice water content generated in icing tunnels.
SAE MOBILUS Subscription

Wiley SAE MOBILUS® eBook Package

2018-03-23
Committed to being the primary source for aerospace and ground vehicle engineering resources, SAE International has added the full compilation of our Wiley eBook collections to the SAE MOBILUS® technical resource platform. Purchasable as an annual subscription and containing the titles from the Wiley Aerospace Collection, the Wiley Automotive Collection, the Wiley Computer Systems Collection, and the Wiley Cyber Security Collection.
SAE MOBILUS Subscription

Wiley Computer Systems Collection Add-On

2018-03-23
As an annual subscription, the Wiley Computer Systems Collection Add-On is available for purchase along with one or both of the following: Wiley Aerospace Collection Wiley Automotive Collection The titles from the Wiley Computer Systems Collection are included in the SAE MOBILUS® eBook Package. Titles: Real-Time Embedded Systems FlexRay and its Applications: Real Time Multiplexed Network Multiplexed Networks for Embedded Systems: CAN, LIN, FlexRay, Safe-by-Wire... Object Detection and Recognition in Digital Images: Theory and Practice Computer Vision in Vehicle Technology: Land, Sea, and Air Mobile Intelligence Other available Wiley collections: Wiley SAE MOBILUS eBook Package Wiley Aerospace Collection Wiley Automotive Collection Wiley Cyber Security Collection Add-On (purchasable with the Wiley Aerospace Collection and/or the Wiley Automotive Collection)
SAE MOBILUS Subscription

Wiley Aerospace Collection

2018-03-23
Purchasable as an annual subscription and containing 30 eBook titles, the Wiley Aerospace Collection covers valuable engineering subject matter, such as aircraft fuel systems, aerodynamics, and propulsion. The series also goes beyond engineering, including eBooks on planning, logistical issues, and how human behavior can be managed and controlled while operating aircraft.
Technical Paper

Wick Characterization by Image Analysis

2001-07-09
2001-01-2238
The microstructure characterization of tubular wicks is discussed using an image analysis method, mercury intrusion porosimetry and Arquimedes method. The central objective of this work is to determine the wide convenience of the image analysis technique for wick characterization. It is demonstrate that the image analysis technique is an appropriate tool to determine correlation function, total porosity and pore size distribution in two-dimensional (2-D) binary images of microstructures. The correlation function is used to simulate the 3-D reconstruction of porous structure. The images were obtained from a set of wick samples made of sintered nickel, through scanning electronic microscopy (SEM). A computer program (Imago) was developed and used in the work. The mercury intrusion porosimetry is also used to provide information about the breakthrough diameter of porous material. Results show porosity of about 60% and effective pore size less than 4 μm.
Technical Paper

Welding With a High-Power CO2 Laser

1974-02-01
740863
The application of a production-oriented high-power CO2 laser system for the welding of auto underbody components is reported. Sheet metal sections, varying in thickness from 0.060-0.135 in, are welded at speeds up to 500 in/min at 6 kW. An overview of recent developments in laser welding is presented along with a discussion of the laser deep-penetration weld phenomenon. A comparison is made between laser and electron-beam welding performance.
Technical Paper

Wake Structure Diagnostics of a Flapping Wing MAV

2005-10-03
2005-01-3198
Experiments were performed to better understand the aerodynamic flow field of a flapping-wing micro air vehicle. High-resolution laser sheet flow visualization and particle image velocimetry (PIV) analyses have shown the presence of folded vortex filaments that are trailed from the tip and root of the wing, which are combined with a shed dynamic stall vortex with a strong spanwise flow toward the wing tip. This leading-edge vortex gains strength as the translational motion of the wing accelerates through mid-stroke. There is a subsequent shedding of this vortex, but with the simultaneous formation of another leading-edge vortex. The generation of the second vortex occurs before the first vortex reaches mid-chord, enhancing overall lift. This second vortex moves along the chord during supination, before finally being shed from the trailing-edge of the wing.
Technical Paper

Wake Imaging System Applications at the Boeing Aerodynamics Laboratory

1985-10-01
851895
The wake imaging system (WIS) for rapid mappings of wind tunnel model flowfields is described and a summary of recent results is presented. Three different types of systems are discussed. These are: Photographic WIS in low-speed wind tunnels. Computer graphics WIS in transonic wind tunnels. Flying strut traverser for large low-speed wind tunnels. In addition, progress toward developing a low intrusive WIS for high-pressure transonic wind tunnels and for flight test applications is described.
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