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The UAV market is encountering a significant development in the last decade. There are numerous applications in aerial surveillance, emergency situations, delivery of essential products in remote area which are now conducted via UAVs. In this article are presented the design and manufacturing of an area of microtextured photovoltaic cells with increased efficiency, having physical-mechanical capabilities according to the requirements of aerospace applications. Their realization and integration on an ultralight wing made of composite materials is also an exceptional technological achievement and at the same time, a great challenge, given the demands that arise between the two dissimilar materials

An ultra-thin heat resistant absorber with multi-sized through-hole structure is presented in this paper. The overall thickness of the absorber is only 1mm. The design is based on the absorption of N5 ferrite material and the regulation of absorbing frequency band by multi-dimension through-hole structure. According to the simulation, the absorbing rate achieves more than 80% in the working frequency band of 8-18 GHz under the incidence of liner polarized wave. Compared with N5 ferrite material, the multi-dimension through-holes decrease the weight by about 22.5%. Owe to its thinness and lightness, it will have more applications in the field of aerospace.

This research is focused on the development of a thermally stable perovskite cell designed for operation in space. We describe the methodology used to test both perovskite cells and component materials, in preparation for eventual space qualification.

Advances in the aerospace industry have made reusable spacecraft increasingly important. However, hypervelocity impact damage will seriously affect the performance of aerospace materials. Detecting the impact damage of space debris is an urgent problem to be solved. In addition, there is also the problem of a large area of aerospace materials, and the testing equipment can only handle a partial area. Therefore, this paper proposes an automatic recognition and reconstruction model of local damage regions based on infrared sequence, and proposes an optimized mosaic algorithm for mosaic damage reconstructed images based on matching optimization.

The nondestructive quantification of local grain properties in polycrystalline aerospace materials is an important area of recent research, where information related to mean grain size, grain size distribution, and crystallographic orientation are needed for engineering analysis and remaining life predictions in aerospace engine components. In the present effort, a novel ultrasonic imaging method is described that provides enhanced resolution measurements and characterization opportunities for microstructure states in polycrystalline materials. The method utilizes a standard focused immersion ultrasound approach to send ultrasound into a material system, and a collinear wavefield imaging beam to sense local ultrasound fields on the opposite side of the material. By raster scanning the sample relative to the transducer and wavefield beam positions, a high resolution measurement can be generated that has enhanced sensitivity to local grain property estimation.

This is a status of activities for the SAE Aerospace Division Fiber Optics and Applied Photonics Committee.

X-rays can be employed in a variety of techniques to obtain structural information about materials with atomic scale resolution. Thanks to their non-destructive mode of operation and to their high sensitivity, X-ray techniques represent an effective multi-scale probe, providing details from the atomic level to the long range order of materials. The high brilliance of the X-ray beams produced at synchrotron facilities allows high-quality data collection to be carried out. Such X-ray beams are extremely reliable probes to investigate the effects originated from stress, strain, irradiation, high temperatures, etc. For this reason, synchrotron radiation techniques are not only suitable but desirable tools to characterise and test aerospace components. Here we report several case examples of several synchrotron radiation techniques well-suited to investigate the structure of composite and multiphase materials as those employed for aerospace applications. The deep insight gained by combining such techniques can represent a breakthrough in the development of innovative solutions for aerospace technologies.

The nondestructive quantification of grain feature information in polycrystalline aerospace materials is an important area of recent research, where information related to mean grain size, grain size distribution, and crystallographic orientation is needed for engineering analysis and remaining life predictions in aerospace engine components. In the present effort, the interaction of surface acoustic waves (SAW) with a dualmicrostructure nickel polycrystalline material is studied, where the isolation and direct imaging of backscatter processes is made possible using time-gated wavefield imaging methods. The methods provide a means for studying the time-evolving nature of the backscatter energy fields, which suggest radially-expanding waves are generated by the individual and collective grain scattering events. This basic observation is consistent with longstanding backscatter theory considerations and is being used to understand the root-cause backscatter conditions that contribute to far-field ultrasonic signal capture.

Eight typical flip chip packages were adopted in this study, two domestic, six imported, and five of the six imported were models with experience of aerospace application. The construction and material of these flip chip packages were analyzed, and similarities and differences between the domestic and the imported packages were compared. Construction analysis criteria of flip chip package for aerospace application were summarized based on these results. The results of this study could play an important guiding role in construction analysis of aerospace flip chip package components.

Lightning is one of the most unpredictable and destructive forces in nature, and ensuring the protection and safety of aircraft in flight, as well as other modes of airborne transport, when struck by lightning presents a unique set of engineering challenges. In order to progress into a new generation of conductive carbon composites and/or embedded light-weight lightning protection systems, further scientific understanding is required on the mechanisms and impact of lightning on carbon composite aircraft. This paper recalls how modern lightning research has progressed from deducing information from natural lightning events to reproducible and instrumented lightning generators capable of accurate and repeatable experimentation. Results of investigations on how aerospace materials, with and without lightning protection, react when struck by lightning are presented illustrating the extent of damage that could be caused. Furthermore, methods of studying lightning effects, such as mechanical deflection, chemical element interaction, and temperature measurements, are then presented to illustrate the role of lightning experimentation as a means to help support aspects of modelling such as material behavior, aircraft design and potentially flight performance.

It is an increasing number of the applications of new materials in modern aircraft manufacture, especially composites are largely used in some key parts, such as the rudder and wing. However, more non-destructive problems appear because of the restriction of the traditional non-destructive testing methods for the new materials. In this paper, the principle of infrared thermography about two kinds of heat stimulation methods is introduced, several composite and metal materials used in the aircraft is manufactured as the specimen for the inspection experiments, the temperature decreasing data after heat stimulation is processed and the defects are shown in the thermal images, furthermore, the results of CFRP impact damages inspected by using different kinds of heat stimulations are shown as a comparison, and the advantages and disadvantages of the two methods for this kind of material is analyzed, In addition, the characteristic and develop trend of this technology in aircraft is summarized.

© 2016 IEEE. Recent developments in the areas of metamaterials and high impedance ground planes (HIGPs) have created new opportunities for the development of novel multi-functional aerospace materials. One niche application of such materials is the suppression of electromagnetic surface waves across the outer mold line (OML) of aerospace structures. Doppler tomographic imaging and spectral filtering techniques are used to characterize the performance of a simple numerically simulated HIGP. A tapered HIGP concept is introduced to improve the performance over a range of illumination angles. This tapered HIGP is to be embroidered in a commercial aerospace pre-preg material. Experimental results will be presented at the conference.

The nondestructive quantification of polycrystalline grain feature information in aerospace materials is an important area of recent research, where spatially-resolved measurements related to mean grain size, grain size distribution, and crystallographic orientation are needed for engineering analysis and material state awareness evaluations. In the present effort, the interaction of ultrasonic surface acoustic waves (SAW) with a dual-microstructure nickel polycrystalline material is studied, where an innovative wavefront imaging method is utilized to visualize and study the time-evolving advance of the primary, forward propagating wavefront through microstructure grain features on the material surface. The method involves a first-arrival, time-gated analysis of scanning laser vibrometry signal content, where the apparent motion of the wavefront through individual and clustered grains is observed and attributed to local changes in the orientation-dependent crystallographic slowness.

Natural systems-inspired design (NID) is the transfer of design solutions from biology and other natural sciences to the creation of human-engineered products. Despite the promise of improvements in cost, performance, and reliability, there has been little application of NID to spacecraft engineering. The NASA Engineering and Safety Center (NESC) Robotic Spacecraft Technical Discipline Team is investigating NID solutions for the systems engineering and technology development processes. NID falls into two broad categories: 1) structural- and 2) process-inspired solutions. For structural NID, fiber composites resembling wood and bone micro-architecture have had a major impact on aerospace materials development. However for such products there is no formal, organized standard under which to comprehensively survey the published knowledge base in life sciences and other disciplines for NID solutions, extract those concepts, and insert them methodically into the design cycle of engineered products. Some progress has been made employing genetic algorithms, which are process-oriented biological NID solutions employing simulations of mutation, reproduction, and natural selection to produce engineered products. This approach has produced one of the few solid examples of spaceflight-proven NID hardware, the Ames Evolved Antenna, flown on board the ST-5 and LADEE missions. The lack of a systematic process for incorporating NID solutions into the systems engineering cycle is standing in the way of broadly applying this new approach for achieving innovative improvements for spacecraft, for example for Mars surface operations. The NASA Mars program presents a compelling frontier for NID solutions, particularly for aerial and surface systems where low mass and power consumption, high reliability and survivability, and flexibility of function in a hostile environment are critical. NID concepts for robotic Mars exploration platforms carrying in-situ instruments for the exploration of the atmosphere and the surface and sub-surface of Mars described herein represent only the beginning of what can be possible with NID. Success in NID design for space engineering will require moving beyond simply copying nature to produce a paradigm-shifting change of focus, which will require including NID in the system engineering process and the technology strategies that support it. We recommend three major thrusts to enable this to happen: (1) Ready access by engineering teams to the those knowledgeable about natural systems and technology development, (2) Intelligent search tools to tap natural sciences databases, and (3) Incremental organizational change that encourages the consideration of natural systems from operations concept through the entire mission life-cycle.

Simple, easy-to-use and physically meaningful analytical predictive models are developed for the evaluation of thermal stresses in bi- and tri-material bodies employed in various aerospace electronic and photonic packaging designs. The numerical examples are carried out for a bi-material assembly comprised of a silicon IC and a ceramic substrate, and for 2) a tri-material body obtained as a result of soldering the above assembly onto a copper heat sink. In both cases the solder layer is viewed as the weakest element in the structure. The developed models can be used in physical design and reliability evaluations of assemblies of the type in question. It is suggested that analytical models of the type considered in this paper always precedes FEA simulations and experimentations, especially when there is a need to understand and to explain the physics of the observed or anticipated failure.

Summary form only given. We present results from a TDS imaging system for non-destructive evaluation of aeronautics composite materials, like glass fiber laminate and sandwich structures. Time-of-flight information from reflection measurements allows for 3D reconstruction of test sample volumes. Clear identification and spatial positioning of defects like delamination and foreign inclusion is possible.

Sandwich structures comprising para-aramid paper honeycomb core and carbon fiber epoxy matrix composite facesheets were fabricated for aerospace applications. For the adhesion of honeycomb core and composite facesheets, two different types of adhesive films were used. The curing parameters for adhesive films, including temperature and time, were optimized for maximum bonding strength.

When a pulsed laser ablates the target, the impulse will be imparted to the target due to the ejection of the ablating material. This is called laser ablation impulse coupling effect. The effect can be used in the space debris controlling when it is going to collide with an operational satellite. The analytical model of calculating laser ablation coupling coefficient is given. The result is used as the input value to our assumed simulation, which is that an operational satellite is going to collide with the space debris. The results show that laser can effectively alter the trajectory of space debris.

Advanced alloys are being developed for a variety of critical applications in the aerospace and nuclear industries and the joining together of dissimilar metals is also becoming increasingly important. However, for a joining process to be truly effective in the fabrication step of the component, it must be able to produce sound quality joints without compromising the mechanical properties of the metals being joined. In this paper the diffusion bonding process is discussed as a method for joining complex metals and examples are given and include aluminium metal matrix composites and light alloys such as Ti-6Al-4V and a magnesium alloy (AZ31). The paper highlights the importance of the correct choice of interlayer(s) and shows how the relationship between bonding parameters and changes in joint microstructure relate to property changes of the joint region.

This paper proposes a kind of adaptive noise cancellation method based on EEMD that considers the non-stationary and weak of defect signal of aerospace launcher steel structure. First, the non-stationary defect signals are adaptively decomposed according to EEMD. It can effectively inhibit the folding phenomenon of model that may appear in classical empirical mode decomposition. Then, the product of energy density and average period of IMF components is a constant value. On the basis of the constant value, it can automatically eliminate the decomposed intrinsic mode function. Finally, the signals upon commands from the rest IMF components are reconstituted. The results show that an adaptive de-noising method based on EEMD is fully data-driven, it has more adaptive ability than empirical mode decomposition de-noising method. In conclusion, this method is more conducive to the de-noising of defect signal of the aerospace launcher steel structure.

With the increase of service time of aircraft, the damage in aircraft composite material components may be caused. A uniplanar multi-electrode capacitive sensor is used for detecting the damage in aircraft composite material. In order to improve the sensitivity of the sensor, the optimization for the structure parameters of the sensor with 8 electrodes is carried out. The optimization indexes of the uniplanar capacitive sensor are given and the effects of the structure parameters of the sensor with 8 electrodes on sensitivity are investigated. According to the optimization, a uniplanar capacitive sensor, with 8-electrode on one plane substrate and a ground screen electrode as well as the screen between electrodes, is designed to get the corresponding capacitance information of the measured composite material slab. Two aircraft composite material slabs, one is healthy and the other is notched, are used as a sample for the experiment of detecting the damages. The preliminary simulative and experimental results show that the optimization of the structure parameter of the sensor is important for the sensitivity of the sensor, the measured capacitance decreases after damage occurs in aircraft composite material, and the proposed approach can effectively detect the damage of aircraft composite material.

The possibility to inspect laminates of prepreg carbon fiber reinforced polymer (CFRP) laminates during lay-up fabrication is studied. First ultrasonic properties of the uncured material are determined, this information is used to design an inspection system that is tested during the fabrication of laminates with up to 30 layers, following different compaction schemes and including some Teflon insertions to simulate the presence of delaminations. The paper shows that for the chosen selection of parameters (transducers sensitivity, centre frequency and mold configuration), the inspection is possible, opening a new field of application of air-coupled ultrasonic techniques.

The composite materials, such as fiber-glass and CFRP, are increasingly used for manufacturing of structural components in aeronautics industry due to their high durability and reduced corrosion in comparison with other materials. This leads to aerodynamic characteristics improvement, reduction of aircraft weight, essential fuel economy and, as a result, to reduction of exhaust gas emission and exploitation costs and rise of flight safety. At the same time, adhesive bonding techniques are increasingly used in aeronautic industry for manufacturing of composite structural components instead of traditional rivet-based assembly [1]. Using of terahertz (THz) electromagnetic radiation (0.1...10 THz) is one of the promising methods for non-invasive testing of composites.

This Metal matrix composites (MMCs) are finding widespread use in the automotive and aerospace industry where strength, weight, thermal conductivity and thermal expansion are important. They are a composite of an element or alloy metal bound into a `matrix' structure, formed by a reaction synthesis process. The most common material combinations are aluminum (Al) and silicon carbide (SiC). Because of their composite nature, the properties of MMCs can be tailored to suit the particular application based on the contribution of individual materials. Current applications find them in automotive, aircraft brake rotors and space electronic packaging, where toughness and dimensional stability at temperature extremes are important. Several silicon-carbide particulate (p) reinforced aluminium (SiC/Al) and graphite/ aluminium (Gr/Al), electronic packages have been space-qualified and are now flown on communication satellites and Global Positioning System satellites. The most significant problem in the space power electronic module concept is the issue of adequate thermal management and consequent electrical performance. It is believed that a Metal Matrix Composite (MMC) heat spreader, with high thermal conductivity and low CTE has the potential to solve many of these thermal management issues. Applied to electronics cooling applications, the primary advantage of MMCs is the ability to tailor the CTE to match bonded and mating materials, such as copper, braze material, ceramic substrates, and silicon in one hand and in other hand as the electronics devices get smaller and smaller, self-heating becomes important and changes the electronic performance of device. This thermal-electronic coupling effect often results in thermal runaway and hence the breakdown of the device. In this paper, an investigation of the thermal behavior of space electronics devices using a Metal Matrix Composite Materials, using the Transmission -Line-Matrix (TLM) method, is exposed. The technique has been successful in modeling various heat diffusion and mass transport problems and has proven to be efficient in terms of stability, complex geometries and the incorporation of non linear material properties. The three dimensional results show that the method has a considerable potential in small devices thermal analysis and design. The results show that the development of MMCs for use in the Space Electronics Systems thermal design is quite promising considering the superior thermal characteristics.

Complex composites are widely used in aerospace, automobile industry and other fields. Because parts of complex surface to be detected are usually parts with variable thickness. After analyzing the disadvantages of current testing method, an improved real-time sensitivity adjusting method based on stable amplitude is presented. Part curvatures (convex and concave) have a significant effect on both the ultrasonic response and the scanning resolution requirements. In order to ensure more ultrasonic signals transmitted through composites, transducer should always automatically follow the changing shape of curved surface. A twin-robot testing system is introduced to accomplish testing complex surface automatically. Moreover, the experimental results of testing different complex composites supported the opinion above.

This paper deals with a new method of PEA signal processing used for space materials. The aim of this new approach of deconvolution technique is first to obtain a charge density with an optimized spatial resolution and second to have an estimated charge density without handle any parameters. This new method is compared with the current PEA signal processing widely developed in the literature. After a brief description of the both methods, an experimental comparison is realized with irradiated materials. Results show an enhancement of the spreading of charges at vicinity of electrodes.

Effect of electron beam irradiation on dielectric properties in various insulating materials for spacecraft is investigated using PEA (Pulsed Electro-Acoustic) method. In space environment, spacecraft is exposed to plasma or radioactive-rays. In such condition, multilayer insulating materials covering the spacecraft are charged up. Sometimes the charge accumulation causes to the serious damage to the electric devices and degradation of insulating materials. To investigate the change of the electrical properties of dielectrics by electron beam irradiation, we measure the space charge distributions and the conduction current in some e-beam irradiated materials under dc stress. From the measurement results, it was found that the large amount of charges accumulated in some irradiated materials under dc stress, while almost no charges accumulated in the non-irradiated materials under the same stress.