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The Soft X-Ray Telescope (SXT) is an instrument on the International X-Ray Observatory (IXO). Its flight mirror assembly (FMA) has a single mirror configuration that includes a 3.3 m diameter and 0.93 m tall mirror assembly. It consists of 24 outer modules, 24 middle modules and 12 inner modules. Each module includes more than 200 mirror segments. There are a total of nearly 14, 000 mirror segments. The operating temperature requirement of the SXT FMA is 20°C. The spatial temperature gradient requirement between the FMA modules is ±1°C or smaller. The spatial temperature gradient requirement within a module is ±0.5°C. This paper presents thermal design considerations to meet these stringent thermal requirements.

Humidity control within confined spaces is of great importance for current NASA environmental control systems and future exploration applications. The engineered multifunction surfaces (MFS) developed by ORBITEC is a technology that produces hydrophilic and antimicrobial surface properties on a variety of substrate materials. These properties combined with capillary geometry create the basis for a passive condensing heat exchanger (CHX) for applications in reduced gravity environments, eliminating the need for mechanical separators and particulate-based coatings. The technology may also be used to produce hydrophilic and biocidal surface properties on a range of materials for a variety of applications where bacteria and biofilms proliferate, and surface wetting is beneficial.

The Mars Science Laboratory (MSL) mission to land a large rover on Mars is being prepared for Launch in 2011. A Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) on the rover provides an electrical power of 110 W for use in the rover and the science payload. Unlike the solar arrays, MMRTG provides a constant electrical power during both day and night for all seasons (year around) and latitudes. The MMRTG dissipates about 2000 W of waste heat to produce the desired electrical power. One of the challenges for MSL Rover is the thermal management of the large amount of MMRTG waste heat. During operations on the surface of Mars this heat can be harnessed to maintain the rover and the science payload within their allowable limits during nights and winters without the use of electrical survival heaters. A mechanically pumped fluid loop heat rejection and recovery system (HRS) is used to pick up some of this waste heat and supply it to the rover and payload.

Requirements analysis for aircraft simulators is often driven by photographs and videos of the actual aircraft. An engineer may gather and organize hundreds or even thousands of source photos of various instruments and devices unique to the aircraft. Managing all of this source information and referencing it to generate software requirements can be challenging and time-consuming. This paper explores Content Based Image Retrieval (CBIR) techniques to automatically process and search those images to generate basic requirements and to facilitate reuse. An unsupervised clustering algorithm groups source images based on minimal user input. Images processed in this way can also be queried by image similarity, thereby allowing project managers to find common source material among projects. The effectiveness of these techniques is demonstrated on an example cockpit.

The paper presents the results of a CFD study for predictions of ventilation characteristics and convective heat transfer within the Shuttle Orbiter middeck cabin in the presence of seven suited crewmember simulation and Individual Cooling Units (ICU). For two ICU arrangements considered, the thermal environmental conditions directly affecting the ICU performance have been defined for landing operation. These data would allow for validation of the ICU arrangement optimization.

An infrared laser absorption technique has been developed to measure in-cylinder concentrations of CO in an optical, automotive HCCI engine. The diagnostic employs a distributed-feedback, tunable diode laser selected to emit light at the R15 line of the first overtone of CO near 2.3 μm. The collimated laser beam makes multiple passes through the cylinder to increase its path length and its sampling volume. High-frequency modulation of the laser output (wavelength modulation spectroscopy) further enhances the signal-to-noise ratio and detection limits of CO. The diagnostic has been tested in the motored and fired engine, exhibiting better than 200-ppm sensitivity for 50-cycle ensemble-average values of CO concentration with 1-ms time resolution. Fired results demonstrate the ability of the diagnostic to quantify CO production during negative valve overlap (NVO) for a range of fueling conditions.

MIL-STD-704 defines power quality in terms of transient, steady-state, and frequency-domain metrics that are applicable throughout a military aircraft electric power system. Maintaining power quality in more electric aircraft power systems has become more challenging in recent years due to the increase in load dynamics and power levels in addition to stricter requirements of power system characteristics during a variety of operating conditions. Further, power quality is often difficult to assess directly during experiments and aircraft operation or during data post-processing for the integrated electric power system (including sources, distribution, and loads). While MIL-STD-704 provides guidelines for compliance testing of electric load equipment, it does not provide any instruction on how to assess the power quality of power sources or the integrated power system itself, except the fact that power quality must be satisfied throughout all considered operating conditions.

Advanced technologies in LED's have the potential to reduce maintenance and improve aircraft safety. Aircrafts need adequate illumination for night time landing. New technology such as high-power LEDs allow for better suited light distributions, more whitish light compatible for mesopic lighting conditions and reduced glare in adverse weather conditions. LEDs and the associated electronics are more susceptible to harsh environmental conditions and this needs to be accounted for in the design of the equipment. Highly conductive metal core PCBs (MCPCB) allow for adequate cooling in a mirror telescopic optical arrangement when coupled with robust active cooling. Closed loop optical feedback of output flux ensures constant performance over the lifetime of the light unit and allows for indication of remaining useful life to the operator to plan maintenance activities. Parylene coating inhibits premature degradation of the LEDs induced by water vapor and corrosive gases.

Automated countersink measurement methods which require contact with the workpiece are susceptible to a loss of accuracy due to cutting debris and lube build-up. This paper demonstrates a non-contact method for countersink diameter measurement on CFRP which eliminates the need for periodic cleaning. Holes are scanned in process using a laser profilometer. Coordinates for points along the countersink edge are processed with a unique filtering algorithm providing a highly repeatable estimate for major and minor diameter.

In contemporary industries the demand for very accurate robots is continuously growing. Yet, robot vendors are limited in the achievable accuracy of their robots, as they have no means to provide a direct end-effector feedback. Therefore, most approaches aim to identify an accurate model of the robotic system, thus providing compensation factors to correct the deflections. Models, however, are unable to represent the real physical system in a sufficient manner for path correction. The non-linearities in robotic systems are difficult to model and the dynamics cannot be neglected. A better approach is, therefore, to use direct end-effector position and orientation feedback from an external sensor as, e.g. a Leica laser tracker. The measured data can directly be compared to the nominal data from the path interpolator. Hence, the data are independent of the kinematic robot model.

Aircraft development projects at Bombardier Aerospace involve a large number of tasks executed by a network of professionals from various disciplines. As the complexity of products and the development process increases, it becomes more difficult to manage the interactions among tasks and people. In fact, it may be impossible to even predict the impact of a single design decision across the development process. At Bombardier, investigation has shown that there was a lack of communication between design processes when dealing with aeroelasticity information. This resulted in duplicated design effort, reduced quality, and increased time to complete tasks when small design changes from one task induced delays in other tasks. Processes that deal with aeroelasticity work integrate system inertial, aerodynamics and structural information to make aircraft models and perform analyses. These processes have been creating similar models to perform aeroelasticity analyses.

Numerous pyrotechnic devices have been employed in satellite launch vehicle missions, generally for the separation of structural subsystems such as stage and satellite separation. The detonation of the pyrotechnic devices generates shock waves characterized by high accelerations and vibrations which cause the failure of electronic components. To reduce the possibility of failure, many researchers have attempted to develop various experimental and numerical simulation methods for investigating pyroshock behavior to determine the appropriate placement of sensitive equipment. However, most of those methods have limitations such as low flexibility and high costs in the experimental methods and relatively low efficiency and reliability in the numerical methods. This study proposes a simple experimental method for pyroshock prediction using only laser pulse excitation and in-line filters for composite structure.

The purpose of this work is to evaluate the efficiency of several calibration methods applied to a six-axis industrial (serial) robot. Specifically, the absolute position accuracy of a Fanuc LR Mate 200 iC industrial robot is improved using two calibration models. The first model is purely kinematic, and takes into account all geometric parameters. The second model considers, in addition, five compliance parameters related to the stiffness in joints 2, 3, 4, 5, and 6. For both models, the so-called calibration (or identification) robot configurations are selected based on an observability analysis. For each model, the efficiency of five different observability indices are compared. The parameter identification is based on the forward kinematic approach, where only the residual of the calibration positions is minimized.

For decades optical camera systems have been used by Broetje-Automation to locate pilot holes and find product orientation on NC-controlled positioner systems. Measurement tolerance requirements were and are in the range of +/− 0.2 mm. Recent developments enhance the sensor technology function from pure hole detection to new features like Fastener Head Height Measurement and Countersink Diameter Measurement. While head height measurement has to go 3D by enhancing the planar sensors to head protrusion measurement, the Countersink measuring tolerances are much smaller than “simple” hole detection, in fact require more than a magnitude tighter tolerances. This paper will present how Broetje-Automation solved the issue of a 20 plus fold accuracy increase, the 3D capability of the one eyed camera and all accompanied by a more robust evaluation software.

Stringer misplacement in the latest design of full CFRP wing covers causes cost and lead time in the further processes due to reworks in the torsion box assembly., To improve and solve this matter, ARITEX has developed an automated Laser assisted Stringer positioning system that allows the flexible, one-by-one and accurate position of the non-cured Stringers in the wing cover. This paper describes how ARITEX has developed and implemented this system in two different CFRP wings using the same technical concept adapted to the context and geometry of each aircraft, and how the targets were achieved reducing the misplacement problem from previous projects.

We applied ultrasonic propagation imaging (UPI) system for rapid and reliable quality control of fuel tanks for a space launcher. The fuel tank is an aluminum-lined CFRP propellant tank. The UPI system uses Q-switched laser (QL) to generate ultrasonic wave on the test specimen, and laser mirror scanner (LMS) to control the laser impinging point that scans the area of interest with high speed. Each ultrasonic wave generated by laser impinging was received by a piezoelectric sensor with coordinate information of the scanned area. After ultrasonic propagation image processing, results with impact damage and manufacturing defect information of the fuel tank were presented.

In this paper, we present an image registration approach to cope with inter-image illumination changes of arbitrary shape in order to monitor the development of micro-pitting in transmission gears. Traditional image registration approaches do not typically account for inter-image illumination variations that negatively affect the geometric registration precision. Given a set of captured images of gear surface degradation with different exposure times and geometric deformations, the correlation between the resulting aligned images is compared to a reference one. The presented image registration approach is used with an online health monitoring system involving the analysis of vibration, acoustic emission and oil debris to follow the development of micro-pitting in transmission gears. The proposed monitoring system achieves more registration precision compared to competing systems.

The article presents convective heat transfer phenomenon by analytically and empirically taken data and CFD based model analysis. 1000 hp ASz-62IR aircraft radial engine is the object of research. This engine is being continuously operated on M18 Dromader and AN-2 aircraft. To recount heat oriented phenomena a three-dimensional CFD model was developed that accounts circumfluent flow around cylinder and cylinder head engine surfaces. The geometry includes M18 Dromader frontal airframe elements to account their influence on cooling air flow. The simulation has been conducted as a steady-state flow. Geometry and setup specific swirls and backflows were observed that increase cylinder and cylinder head rear side heat transfer coefficients. Flow along cooling fins was analysed, connecting their heat transfer coefficient dependency. Results show that local air velocity has big influence on heat flux passed by fin walls.

Aviation regulations requires that engine mounts, and other flight structures located in designated fire zones must be constructed of fireproof material so that they are capable of withstanding the effects of fire. Historically, steel is defined as being inherently fireproof, however, titanium was not. Therefore, a fireproof test was conducted using 6AL-4V titanium structure for the attachment of the propulsion system on a mid-size business jet to satisfy FAA Federal Aviation Requirement 25.865. To determine if the titanium structure would be able to support normal operating loads during the fire event, finite element analysis was performed on the titanium structure simulating the fire test. The fire test simulates a fire on the aircraft from the propulsion system by using a burner with jet fuel exposing the component to a 2000 °F (1093°C) flame. The 2000 °F (1093°C) Flame is calibrated based on FAA Advisory Circular AC20-135.

In many existing AFP cells manual inspection of composite plies accounts for a large percentage of production time. Next generation AFP cells can require an even greater inspection burden. The industry is rapidly developing technologies to reduce inspection time and to replace manual inspection with automated solutions. Electroimpact is delivering a solution that integrates multiple technologies to combat inspection challenges. The approach integrates laser projectors, cameras, and laser profilometers in a comprehensive user interface that greatly reduces the burden on inspectors and decreases overall run time. This paper discusses the implementation of each technology and the user interface that ties the data together and presents it to the inspector.