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The term “smart structures” is commonly used for structures which have the ability to adapt to environmental conditions according to the design requirements. As a rule, the adjustments are designed and performed in order to increase the efficiency or safety of the structure. Combining “smart structures” with the “sophistication” achieved in materials science, information technology, measurement science, sensors, actuators, signal processing, nanotechnology, cybernetics, artificial intelligence, and biomimetics,〔Wadhawan, V.K. (2005) Smart Structures and Materials. Resonance (). Available from: http://www.ias.ac.in/resonance/Nov2005/pdf/Nov2005p27-41.pdf (30 July 2012 ).〕 one can talk about Smart Intelligent Structures. In other words, structures which are able to sense their environment, self-diagnose their condition and adapt in such a way so as to make the design more useful and efficient. The concept of Smart Intelligent Aircraft Structures offers significant improvements in aircraft total weight, manufacturing cost and, above all, operational cost by an integration of system tasks into the load carrying structure.〔Speckmann, H., Roesner, H. (2006). Structural Health Monitoring: A Contribution to the Intelligent Aircraft Structure, () ECNDT 2006 – Tu. 1.1.1, Airbus, Bremen, Germany. Available from: http://www.ndt.net/article/ecndt2006/doc/Tu.1.1.1.pdf (30 July 2012 ).〕 It also helps to improve the aircraft’s life cycle and reduce its maintenance.〔Dufault, C.F. and Akhras, G., (2008). Smart Structure Applications in Aircraft. The Canadian Air Force Journal, (), p. 31-39. Available from: http://www.airforce.forces.gc.ca/CFAWC/eLibrary/Journal/Vol1-2008/Iss2-Summer/Sections/06-Smart_Structure_Applications_in_Aircraft_e.pdf (30July 2012 ).〕 Individual morphing concepts also have the ability to decrease airframe generated noise and hence reduce the effect of air traffic noise near airports. Furthermore, cruise drag reductions have a positive effect on fuel consumption and required take-off fuel load. == Morphing structures == Fixed geometry wings are optimized for a single design point, identified through altitude, Mach number, weight, etc. Their development is always a compromise between design and off-design points, referred to a typical mission. This is emphasised for civil aircraft where flight profiles are almost standard. Nevertheless, it may occur to fly at high speeds and low altitude with light weight over a short stretch or to fly at low speeds and high altitude with maximum load for a longer range. The lift coefficient would then range between 0.08 and 0.4,〔H. P. Monner, D. Sachau, E. Breitbach, "Design Aspects of the Elastic Trailing Edge for an Adaptive Wing”, RTO AVT Specialists’ Meeting on “Structural Aspects of Flexible Aircraft Control”, Ottawa (CAN), 18–20 October 1999, published in RTO MP 36〕〔J. J. Spillman, “The use of variable camber to reduce drag, weight and costs of transport aircraft”, Aeronautical Journal, Vol. 96, No. 951, pp. 1-9, 1992〕 with the aircraft experiencing up to 30% weight reduction as the fuel is consumed.〔H. Ahrend, D. Heyland, W. Martin, “Das Leitkonzept ‘Adaptiver Fltiuegel’ (ADIF) DGLR-Jahrestagung, DGLR-JT97-147, Muenchen 1997〕 These changes could be compensated by wing camber variations, to pursue optimal geometry for any flight condition, thus improving aerodynamic and structural performance Existing aircraft cannot change shape without aerodynamic gaps, something that can be solved with Smart Intelligent Structures. By ensuring the detailed consideration of structural needs throughout the entire lifetime of an aircraft and focusing on the structural integration of needed past capabilities, Smart Intelligent Aircraft Structures will allow aircraft designers to seriously consider conformal morphing technologies. The reduced drag during take-off, cruise and landing for future and ecologically improved civil aircraft wings can be achieved through naturally laminar wing technology, by incorporating a gapless and deformable leading edge device with lift providing capability. Such a morphing structure typically consists of a flexible outer skin and an internal driving mechanism (Figure 1). Current aircraft designs already employ winglets aimed at increasing the cruise flight efficiency by induced drag reduction. Smart intelligent Structures propose a state of the art technology that incorporates a wingtip active trailing edge, which could be a means of reducing winglet and wing loads at key flight conditions. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Smart Intelligent Aircraft Structures」の詳細全文を読む スポンサード リンク
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