摘要：A new decentralized control for aircraft engines is proposed. In the proposed control approach, aircraft engines are considered as uncertain large-scale systems composed of interconnected uncertain subsystems. For each subsystem, the time-varying uncertainty, including parameter disturbances and interconnections in/between subsystems, is depicted by a class of general nonlinear functions. A fractional robust decentralized control with two parts, the nominal one and the fractional one, is presented. The nominal control guarantees the asymptotical stability of the engine system without uncertainty. The fractional part aims at overcoming the influences of uncertainty. Compared to the previous studies, the presented control provides not only an extra flexibility for the system performance tuning by the fraction-type gain but also a facility for the control input calculation. The proposed control approach is applied to a turbofan engine with two subsystems. The computer simulation shows that, in the flight envelope, the fractional control not only guarantees the closed-loop system uniform boundedness and ultimate uniform boundedness but also shows good economy.

摘要：When the wing of Oblique Wing aircraft(OWA) is skewed, the center of gravity, inertia and aerodynamic characteristics of the aircraft all significantly change, causing an undesirable flight dynamic response, affecting the flying qualities, and even endangering the flight safety. In this study,the dynamic response of an OWA in the wing skewing process is simulated, showing that the threeaxis movements of the OWA are highly coupled and present nonlinear characteristics during the wing skewing. As the roll control efficiency of the aileron decreases due to the shortened control arm in an oblique configuration, the all-moving horizontal tail is used for additional roll and the control allocation is performed based on minimum control energy. Given the properties of pitchroll-yaw coupling and control input and state coupling, and the difficulty of establishing an accurate aerodynamic model in the wing skewing process due to unsteady aerodynamic force, a multi-loop sliding mode controller is formulated by the time-scale separation method. The closed-loop simulation results show that the asymmetric aerodynamics can be balanced and that the velocity and altitude of the aircraft maintain stable, which means that a smooth transition is obtained during the OWA's wing skewing.

摘要：Commercial aircraft family design can reduce development costs, shorten development cycles, and expand the market coverage of aircraft. Commercial aircraft family development has become one of the most important features of modern aircraft design. This paper explores the effects of commonality on different aircraft models in a commercial aircraft family. The existing product commonality indexes are summarized and their limitations in the application to aircraft design are discussed. Then a new component commonality index is proposed based on the component decomposition structure. A model for calculating the aircraft program value is established,which considers development costs, manufacturing costs, sale price, operation costs and residual costs. The effects of aircraft commonality on time and economic costs of both development and manufacturing, and on sale price, are analyzed and quantified. The commonality evaluation strategy is obtained, which features comprehensive consideration of the aircraft program value and time costs. The break-even analysis of aircraft is proceeded on the basis of costs and price data. By using a real option method, the strategy considers the uncertainty of the aircraft program and the flexibility of the manufacturer. This strategy proves to be rational and applicable to aircraft design based on the calculation of three examples and the analysis of parameter sensitivity.

摘要：The paper overviews the state-of-art of aircraft powered by hybrid electric propulsion *** research status of the design and energy management of hybrid aircraft and hybrid propulsion systems are further *** first contribution of the review is to demonstrate that,in the context of relatively underdeveloped electrical storage technologies,the study of mid-scale hybrid aircraft can contribute the most to both theoretical and practical ***,the profits and potential drawbacks of applying hybrid propulsion to mid-scale hybrid airplanes have not been thoroughly ***,as summed in the overview of design methodologies,the multi-objective optimization transcends the single-objective *** potential of the hybrid propulsion system can be thoroughly evaluated in only one optimization run,if several objectives optimized *** there are few researches covering the conceptual design of hybrid aircraft using multi-objective *** review of the most popular energy management strategies discloses the third research gap—current methodologies favoured in hybrid ground vehicles do not consider the aircraft ***,both non-causal and causal energy management are needed for performing a complicated flight mission with several sub-tasks.

摘要：With projections indicating an increase in mobility over the next few decades andannual flight departures expected to rise to over 16 billion by 2050,there is a demand for theaviation industry and associated stakeholders to consider new forms of aircraft and *** requirements are recognized as a key driver in *** airline is the principalcustomer for the aircraft *** passenger is,in turn,the airline's principal customerbut they are just one of several stakeholders that include aviation authorities,airport operators,air-traffic control and security *** passenger experience is a key differentiator usedby airlines to attract and retain custom and the fuselage that defines the cabin envelope for thein-flight passenger experience and cabin design therefore receives significant attention for newaircraft,service updates and *** making in design is crucial to arrivingat viable and worthwhile cabin *** litle innovation will result in an aircraftmanufacturer and airlines using its products falling behind its *** much mayresult in an over-extension with,for example,use of immature technologies that do not havethe necessary reliability for a safety critical industry or sufficient value to justify the develop-ment *** multiple requirements associated with cabin design,can be viewed as an area for optimisation,accepting trade-offs between the various *** design,however,is often defined as developing a concept that resolves the contradictions and takes the solutiontowards a win-win *** our understanding and practice of design allows forbehaviors that enhance design thinking through divergence and convergence,the use ofabductive reasoning,experimentation and systems *** paper explores and definesthe challenges of designing the aireraft cabin of the future that will deliver on the multiplerequirements using experiences from the A350 XWB and future cabin design

摘要：The basic concepts and advantages of more/all electric aircraft （M/AEA） are briefly addressed. The combined starter/generator （CS/G） system is introduced as a key technology to enable M/AEA. Some important performance requirements for CS/G system are obtained. Based on these requirements, a high speed switched reluctance machine （SRM） is designed to operate as a starter/generator. The entire design process is mainly divided into two stages： electromagnetic design and thermal design. In electromagnetic design stage, the electromagnetic structure and dimensions of the machine and the number of phase winding turns per pole are obtained; the topology and main technical details of the converter are briefly introduced as well. In thermal design stage, a liquid-cooling system is designed based on the thermal analysis of the machine. In the end, the performances of the designed SRM are basically verified by simulation. To get high performances, the exciting angles are optimized in two different operating modes respectively, and the optimized performances in the motoring mode are given as well.

摘要：To increase the efficiency of the multidisciplinary optimization of aircraft, an aerodynamic approximation model is improved. Based on the study of aerodynamic approximation model constructed by the scaling correction model, case-based reasoning technique is introduced to improve the approximation model for optimization. The aircraft case model is constructed by utilizing the plane parameters related to aerodynamic characteristics as attributes of cases, and the formula of case retrieving is improved. Finally, the aerodynamic approximation model for optimization is improved by reusing the correction factors of the most similar aircraft to the current one. The multidisciplinary optimization of a civil aircraft concept is carried out with the improved aerodynamic approximation model. The results demonstrate that the precision and the efficiency of the optimization can be improved by utilizing the improved aerodynamic approximation model with ease-based reasoning technique.

摘要：This paper covers a micro sensor analog signal processing circuit system（MASPS） chip with low power and a digital signal processing circuit board implementation including hardware connection and software design. Attention has been paid to incorporate the MASPS chip into the digital circuit *** ultimate aim is to form a hybrid circuit used for mixed-signal processing,which can be applied to a micro sensor flow monitoring system.

摘要：Vee-tail configuration is an unconventional tail configuration for commercial transport aviation, the use of which could suppose reductions on CO2 emissions. The conceptual design criteria have been selected inspired on the certification requirements established by the aviation regulation in force. They are static stability in cruise, control after Critical Engine Failure(CEF),control in crosswind landing, and trim in these three conditions. The study is carried out through a combination of semi-empirical techniques and Vortex-Lattice Methods(VLM) and thus this analyses the consequences of applying these criteria to a reference aeroplane substituting its conventional tail by a parametrised Vee-tail configuration. The Vee-tail is defined by four parameters:span, root chord, taper ratio and dihedral angle. The results of the study establish a relation between the parameters in order to accomplish the proposed conceptual design criteria. To sum up, minimum and maximum limits are obtained for dihedral angle depending on the combination of the rest of parameters. In addition, a design restriction to the yawing trailing-edge tail control is reached when the results are analysed, demonstrating that its minimum size must be between 60%and 80% of the half-span of the tail, depending on the Vee-tail geometry.

摘要：Three new control factors are presented for calculating the multipole mode number （MMN） efficiently and precisely. The effects of these control factors on the number of integral samples and the precision of multilevel fast multipole algorithm （MLFMA） are investigated. A new approach based on control factors which is proven to be able to improve the computational efficiency and reduce the needed memory significantly as well as ensuring the proper precision. For three aircraft models,the improved MLFMA is employed to analyze their multi-frequency scattering characteristics. It is found that aircraft shape can influence radar cross section （RCS） in different frequency zones. Both the multi-frequency RCS reduction characteristics of shape stealth aircraft and the conventional aircraft with stealth design taken into account are investigated,and the results show that shape stealth exhibits significant RCS reduction in the resonance and high-frequency zones,and with a weaker influence in the Rayleigh zone. Compared with radar absorbing material （RAM）,shape stealth yields a wider multi-frequency RCS reduction. The above-mentioned results can be applied to stealth design for multiple frequencies or even for all frequencies.