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ARINC 818, titled Avionics Digital Video Bus (ADVB), is a video protocol standard for high-bandwidth, low-latency, critical video systems. Since its introduction three years ago, many commercial and military aerospace programs have adopted the protocol, including the 787, A400M, and the A350XWB. A description of the protocol and its technical benefits is provided followed by an overview of how it is used in various systems, such as: infrared and optical sensors, map/chart systems, synthetic vision, HUDs, MFDs, video concentrators, and other subsystems. Future uses of the protocol are also explored.

This report describes the design, assembly, and testing of a modified, re-circulating drip flow reactor to quantify the electrical, optical, and thermal performance of solid-state ultraviolet (UV) lighting and semi-conducting photocatalyst for potable water disinfection by advanced oxidation processes. The reactor test assembly incorporates high-output UV-A Light Emitting Diodes (LEDs) with active thermal control to reject heat and generate reactive oxygen species from immobilized titanium dioxide attached to borosilicate glass in the laminar flow stream. Compared with UV-excimer and UV-mercury arc lamps, the UV-A LED system demonstrated excellent thermal stability and good electrical and optical performance.

SAE ARP 4260 Photometric and Colorimetric Measurement Procedures for Airborne Electronic Flat Panel Displays [1] has recently been revised. This new revision reaffirms that ARP 4260 is pertinent to the aviation industry, changes the content to keep up with the state of the art, and adds clarification where needed. ARP 4260 contains methods used to measure the optical performance of airborne electronic flat panel display systems and is referenced in SAE ARP 4256, Design Objectives for Liquid Crystal Displays for Part 25 (Transport) Aircraft [2] and in SAE AS 8034, Minimum Performance Standard for Airborne Multipurpose Electronic Displays [3].

SCALE is a modular, non-contact, in-line measurement system. It measures the diameter of the countersink directly after the drilling, the amount and distribution of sealant in the open hole, and the head height of the fastener as well as pressed out sealant (cf. Figure 1). The system is fast and reliable and the out coming information is reliable and trustworthy. Until now the system could not measure the inner diameter of the hole. The reason for this is that it is not possible to detect the inner diameter with a camera that looks only at the top of the component. But as our customers make the request to us, we decided to develop an optical hole probe system which is fully integrated in the auto fastening process. We think that a mechanical system cannot fulfill the customer expectations in terms of reliability, low maintenance, precision and speed. Only a non-contact system can measure permanently safe and fast the inner diameter of holes.

After a long “incubation” period, MEMS are finally strongly coming out on the marked. The integrated telemetry and the photo-voltaic power source are among the attractive features of the integrated MEMS applications. The tendency is more and more seen to small integrators, which use OEMs and build systems for market demanded applications. However, the products offered by the market at this time are mostly limited to static detection or inertial systems. The temperature range of the dominant applications quite significantly limits the measurement capabilities of the system. Aerospace systems are not necessary falling within the normal temperature range. The need of enhanced performance and safety of the gas turbine engines require pressure measurements at temperature that exceed 500 °C. Apart from the physics, the principle of measurement, fabrication technology, signal data processing, packaging represents a challenging task.

This paper presents the development of a 3-D measurement system capable of measuring free-form surfaces through the combination of a light sheet optical sensor and a mechanical arm. It includes a basic description of the equipment used in this work, focusing on the methodology and procedures which allow both systems be integrated. Notes about the dedicated software that determines the relative position and orientation of the light sheet sensor to the mechanical arm coordinate system are also presented. Finally, the paper presents some results obtained trough the integrated system use, emphasizing its potential industry application.

The BepiColombo mission to planet Mercury requires the availability of advanced thermal control materials to cope with the extreme heat and radiation fluxes exposed to in the vicinity of Mercury. In a first activity, a new Multi-Layer Insulation has been developed able to withstand the high temperatures and particle fluxes. Advanced materials are used in the MLI for the reflection screens as well as for the spacers. In addition, a sun shield has been defined using a ceramic fabric. In a current activity a Solar Reflector Coating, an Optical Surface Reflector and an Infrared Rejection Device are being developed. This paper presents the current status in the development of the thermal insulation and other thermal control components required for the BepiColombo mission. The selection of the materials is presented and, as far as already available, results from the characterization testing.

The main idea of paper is to present the survey of current tendencies in micro-satellites' thermal control concepts that can be rational and useful for posterior missions due to intensive dissemination of satellites of such type. For this purpose the available literature information and lessons learned by the National Technical University of Ukraine during the elaboration of thermal control hardware for micro-satellites Magion 4, 5 [1], BIRD [2] and autonomous thermal control systems for interplanetary missions VEGA [3], PHOBOS [4] have been used. The main parameters taken into consideration for analysis are the satellite sizes, mass, power consumption, orbit parameters and altitude control peculiarities, thermal control description. It was defined that passive thermal control concepts are widely used, excepting autonomous temperature regulation for sensitive components such as batteries, high precision optics, some types of sensors.

Sciamachy is a Dutch/German Earth Observation Instrument on board of the European Envisat satellite, which was launched on March 1st 2002. The goal of the instrument is to observe concentrations of multiple trace gases in the upper atmosphere. Due to the character of the instrument special thermal control methods have been incorporated in the instrument design. Amongst these are the active thermal control loops for the detector modules and the optical bench module. The 8 detector modules, which are cooled with a passive cooler to circa 150 - 240 K, are stabilized with three heaters that are controlled via telemetry. The optical bench module is provided with three feedback-controlled heater loops.

The INTERnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) is an ESA observatory scientific satellite which was successfully launched on the 17th of October 2002. The payload consists in four instruments : an optical camera (OMC), a X-ray monitor (XRM), an imager (IBIS) and a spectrometer (SPI). The spectrometer (20 keV-8 MeV energy range, 2.3 m high, 1.1 m diameter, around 1300 kg) has been supplied by CNES where this instrument has been managed, assembled and tested before delivery to ESA for satellite level activities. This paper describes the spectrometer flight model thermal design achieved thanks to the different international partners, gives and overview of the cryostat used to cool down the detection plane and exposes the thermal validation plan used at instrument level (thermal mathematical model and thermal test philosophy, cryostat thermal validation). We then focus on in-flight performances and compare them to expected ones.

This study investigated the possibility of detecting water deficit stress in plants by using optical signals collected from leaves. Two theoretical approaches have been investigated. In principle, chlorophyll fluorescence can be used to measure generally stressful situations in plants. Our review, however, found that simple ratios of coarsely time-resolved chlorophyll fluorescence, such as maximum fluorescence over fluorescence at steady state, appear to be incapable of adequately distinguishing water stress from other stress factors. A second principle being investigated involves correlation of light absorption within leaves to leaf-water-content using water absorbing and non-water absorbing wavelengths. Our investigation concentrated on defining and eliminating as many extraneous variables as possible.

As part of the PRU project a new plant lighting system has been developed. System design focused on light source development, chamber optical performance improvements and electronics optimization. Central to the lighting system performance is a high density LED Light Engine, enabling increased spectral diversity, higher irradiance levels, enhanced uniformity and improved efficiency. Chamber wall surface materials were tested to minimize the vertical irradiance gradient and improve planar uniformity. Total lighting system efficiency was improved through the use of switching converter LED drive circuitry. As an alternative to the LED light source, an advanced planar fluorescent lighting source has also been developed.

Investigators from three institutions have partnered in a Rapid Technology Development Team whose goal will be the deployment of laser-based sensors for air-constituent measurements on board spacecrafts. The sensors will eventually be based on Type II Interband Cascade (IC) lasers being developed at the Jet Propulsion Laboratory. These lasers will be used in implementations of both photo acoustic spectroscopy based on the use of quartz tuning fork oscillators as a resonant acoustic sensor (QE-PAS) and cavity ring down spectroscopy (CRDS). In the first year of the program, work at Rice and George Washington Universities has focused on the development of both QEPAS and CRDS sensors for ammonia using near infrared lasers. Simultaneously, the JPL portion of the team has fabricated both Fabry Perot and distributed feedback lasers in the mid infrared that can be used for formaldehyde detection.

Both Planck and Herschel satellite are cryogenic payloads, the first one having a cold point around 0.1 [K], the second one around 0.3 [K]. Not only the detectors are cooled, but also major subsystems and systems of the spacecraft’s. The Centre Spatial de Liège (CSL) is involved in the testing of several parts of the spacecraft’s, starting from optical tests on the mirrors or on the telescopes, going on with cryogenic vibration testing of scientific focal plane instruments, ending with the full Planck spacecraft testing. Each test requires temperature lower than 20 [K], in volumes ranging from 1 [m3] to 60 [m3], cooling down several kilograms to more than one ton, and withstanding heat load up to 150 [W] in stabilization. These tests are done is 4 different facilities of CSL, linked to a common cold Helium network. This latter allows full flexibility for operation of the different facilities quasi independently.

We report on a feasibility study of an optical micro-electro-mechanical systems (MEMS) flow sensor to measure flow rate using Moiré fringe displacement of a floating element. Due to constraints on weight, power, and size for space environmental systems, the development of sensor components that minimize the equivalent systems mass (ESM) while maintaining or exceeding required specifications is highly desirable. A feature of the optical detection method is a physical separation of electrical components from the flow stream. The geometric Moiré fringe shift optically amplifies small displacements by the ratio of the fringe pitch to the movable grating pitch that is detected using an external CCD imager, providing an electrically isolated, robust, direct scheme for detecting flow from shear stress induced displacement.

Aim of the Closed Habitat Environmental Control Sensors (CHECS) project has been the setting up of a complete, lightweight sensing system for monitoring the ambient conditions of plant growth in space missions. A complete sensor system has been developed and tested, based on a deep knowledge of plant needs, and on the typical plant behaviour in stress conditions. The main characteristic of the system is its compatibility with Silicon technology. This means high integrability, reduced dimensions, low weight, redundancy, simplicity and high reliability. All the sensors composing the systems have been produced by means of well developed solid state technology, including the MicroSystem Technology (MST) and Porous Silicon Technology (PST). The latter has proved in the last year to have considerable advantages over other approaches.

Herschel is the fourth cornerstone mission in the European Space Agency (ESA) science programme. It will perform imaging photometry and spectroscopy in the far infrared and submillimetre part of the spectrum, covering the 57-670 µm wavelength range. This successor of the Infrared Space Observatory (ISO) is scheduled to be launched by an Ariane 5 in 2007. Once operational Herschel will offer a minimum of three years of routine observations. EADS-ASTRIUM, in charge of the Extended Payload Module, has involved AIR LIQUIDE in the design and manufacturing of major components of the spacecraft cryostat: the two Helium Tanks, all Thermal Links [1.6 K - 9 K], the Optical Bench Helium Cooling Loop, the three Thermal Shields and all the Helium System Tubing from the tanks to the Cryostat Vacuum Vessel. All these elements contribute to the final aim of the system to provide the required cold environment to the Herschel Focal Plane Units.

Dynamic interactions of pairs of co-rotating vortex filaments, typical of those emanating from wing tips and flap tips are studied. Time history of the motion of individual filaments has been obtained in a water tunnel using an optical method. It is demonstrated that before their merger, co-rotating vortex filaments tend to oscillate along preferred directions. Also, the motion appears to be unstable with increasing amplitude over a wide range of frequencies. These conclusions are shown to be consistent with analytical predictions. It is also shown that the merger location correlates well with the vortex strength. Comparisons with analytical and computational results are provided where appropriate.

The thermal design and modeling of NASA’s James Webb Space Telescope (JWST) Integrated Science Instrument Module (ISIM) is described. The ISIM utilizes a series of large radiators to passively cool its three near-infrared instruments to below 37 Kelvin. A single mid-infrared instrument is further cooled to below 7 Kelvin via stored solid Hydrogen (SH2). These complex cooling requirements, combined with the JWST concept of a large deployed aperture optical telescope, also passively cooled to below 50 Kelvin, makes JWST one of the most unique and thermally challenging space missions flown to date. Currently in the preliminary design stage and scheduled for launch in 2010, NASA’s JWST is expected to replace the Hubble Space Telescope as the premier space based astronomical observatory.

SCIAMACHY is a German-Dutch Earth observation instrument which is to fly aboard the Envisat-1 spacecraft It is an 8 channel spectrometer designed to analyse sun light which is scattered on higher layers of the atmosphere. Two of the channels perform measurements in the Infra-Red. For these channels a low and stable temperature level of the instrument is required (< -20 °C) to minimise the impact of IR background radiation on the measurements. Additionally, the system requirement on spectral stability requires the variation in thermal gradient to be very small. This paper presents the flow down from system to thermal requirements and gives a rationale for the Thermal Control Sub-system (TCS) design concept which was established to meet these severe requirements. Added to this are some of the analyses results which support the TCS design. The presented TCS design reflects the PDR status.