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Chinese Journal of aeronautics 2024年第8期37卷 373-387页

作者： Xin SHI Xiang GUO Tao SUO Yingtao YUAN Hongli HE Zhiyong REN School of aeronautics Northwestern Polytechnical UniversityXi’an 710072China International Research Laboratory of Impact Dynamics and its engineering Application Xi’an 710072China Institute of Extreme Mechanics Northwestern Polytechnical UniversityXi’an 710072China Chinese flight test Establishment Xi’an 710089China

This paper proposes a measurement method related to the braking deformation of a complex *** the braking process,the deformation of the wheel includes large amounts of movement,vibration,warping,and distortion.A novel subset assignment and correlation method is proposed to measure the complex *** proposed method can greatly improve the accuracy and stability of the calculation of complex deformations by simplifying the complex deformation into translational deformations in logarithmic coordinate *** to the simulation and actual experiments,the proposed method can be utilized to measure the deformations of up to 100%tensile strain under complex *** to the accuracy verification experiment,the error of the proposed method is less than 50 *** results show that the proposed method can effectively carry out structural deformation measurement in the complex motion and deformation *** proposed method has great significance for structural performance analysis and optimization design considering complex motion and deformation.

关键词： Complex deformation Measurement Digital image correlation Aircraft braking Deformation field

Application of shear-sensitive liquid crystal coating to visualization of transition and reattachment in compressor cascade

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Chinese Journal of aeronautics 2018年第11期31卷 2073-2079页

作者： Ruiyu LI Limin GAO Shuai ZHANG Yongzeng LI Tianyu GAO School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China Collaborative Innovation Center of Advanced aero-engine Beijing 100191China aero-engine flight test Chinese Flight Test EstablishmentXi'an 710089China

The present paper aims at introducing Shear-Sensitive Liquid Crystal Coating(SSLCC)technology into compressor cascade measurement for the first time and serves as a basis for better understanding of the influence from the boundary layers. Optical path layout, which is the most significant difficulty in internal flow field measurement, will be solved in this paper by selfdesigned image acquisition device. Massive experiments with different Mach number and incidence are conducted at a continuous subsonic cascade wind tunnel to capture the boundary layer phenomenon. Image processing methods, such as Three-Dimensional(3-D) reconstruction and Hue conversion, are used to improve the accuracy for transition position detection. The analysis of the color-images indicates that complex flow phenomena including transition, flow separation,and reattachment are captured successfully, and the effect of Mach number and incidence on the boundary layer flow is also discussed. The results show that: the Mach number has a significant effect on transition position; the incidence has little effect on transition position, but it has a great impact on the transition distance and leading-edge separation; influenced by the end-walls, the reattachment occurs in advance under positive angle of attack conditions.

关键词： Compressor cascade Flow visualization Leading edge separation Shear-sensitive liquid crystal coating Transition

Relative orbit determination algorithm of space targets with passive observation

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Journal of Systems engineering and Electronics 2024年第3期35卷 793-804页

作者： DAI Chenchao QIANG Hongfu ZHANG Degang HU Shaolei GONG Baichun Zhijian Laboratory Rocket Force University of EngineeringXi’an 710025China College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 210016China China flight test Research Institute Xi’an 710089China Beijing Institute of Control and Electronic Technology Beijing 100038China

Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for angles-only observability was found by using cylindrical dynamics, however, the solution of orbit determination is still not provided. This study develops a relative orbit determination algorithm with the cylindrical dynamics based on differential evolution. Firstly, the relative motion dynamics and line-of-sight measurement model for nearcircular orbit are established in cylindrical coordinate ***, the observability is qualitatively analyzed by using the dynamics and measurement model where the unobservable geometry is found. Then, the angles-only relative orbit determination problem is modeled into an optimal searching frame and an improved differential evolution algorithm is introduced to solve the problem. Finally, the proposed algorithm is verified and tested by a set of numerical simulations in the context of highEarth and low-Earth cases. The results show that initial relative orbit determination(IROD) solution with an appropriate accuracy in a relative short span is achieved, which can be used to initialize the navigation filter.

关键词： angles-only measurement relative orbit determination cylindrical coordinate differential evolution

A Non-Parametric Scheme for Identifying Data Characteristic Based on Curve Similarity Matching

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1424-1437页

作者： Quanbo Ge Yang Cheng Hong Li Ziyi Ye Yi Zhu Gang Yao School of Automation Nanjing University of Information Science&TechnologyJiangsu Provincial University Key Laboratory of Big Data Analysis and Intelligent SystemsNanjing University of Information Science&Technologyand the Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET)Nanjing University of Information Science&TechnologyNanjing 210044China School of Department of Logistics engineering Shanghai Maritime UniversityShanghai 201306China China Classification Society Nantong Office Nantong 226006China Chinese flight test Establishment Xi’an 710089China School of Mathematics Tsinghua UniversityBeijing 100084China School of Automation Nanjing University of Information Science&TechnologyNanjing 210044China Department of Logistics engineering Shanghai Maritime UniversityShanghai 201306China IEEE

For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity *** the framework of the pro-posed scheme,a Parzen window(kernel density estimation,KDE)method on sliding window technology is applied for roughly esti-mating the sample probability density,a precise data probability density function(PDF)model is constructed with the least square method on K-fold cross validation,and the testing result based on evaluation method is obtained based on some data characteristic analyses of curve shape,abruptness and *** com-parison simulations with classical methods and UAV flight exper-iment shows that the proposed scheme has higher recognition accuracy than classical methods for some kinds of Gaussian-like data,which provides better reference for the design of Kalman filter(KF)in complex water environment.

关键词： Curve similarity matching Gaussian-like noise non-parametric scheme parzen window.

Power Supply for a Wireless Sensor Network： Airliner flight test Case Study

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Journal of Energy and Power engineering 2014年第12期8卷 2058-2064页

作者： Paul Durand Estebe Vincent Boitier Marise Bafleur Jean-Marie Dilhac Sebastien Berhouet CNRS LAAS Toulouse France AIRBUS flight test Instrumentation Toulouse France

In this paper, we present hands-on experience related to on-going implementation in aircraft of power supply for a wireless sensor network deployed for aerodynamic flight tests. This autonomous battery-free power supply is capturing, managing and storing primary energy from the environment, using solar light and PV （photovoltaic） cells. For practical purposes, it is also equipped with an auxiliary power input. The specifications are detailed, the general architecture is presented and justified, and test results are discussed.

关键词： flight tests sensor network solar energy UC (ultracapacitors).

Advanced optimization of gas turbine aero-engine transient performance using linkage-learning genetic algorithm:PartⅡ,optimization in flight mission and controller gains correlation development

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Chinese Journal of aeronautics 2021年第4期34卷 568-588页

作者： Yinfeng LIU Soheil JAFARI Theoklis NIKOLAIDIS aero engine test Department of Hunan Aviation Powerplant Research Institute AECCZhuzhou 412002China Centre for Propulsion engineering School of Aerospace Transport and Manufacturing(SATM)Cranfield UniversityCranfield MK430ALUK

PartⅠhas illustrated the procedures to apply the Linkage Learning Genetic Algorithm(LLGA)in Gas Turbine engine(GTE)controller gains tuning and generated the optimization results for runway conditions from idle to ***,the total pressure and temperature of the engine inlet vary as the changing of altitude and Mach number,which would lead to the variation in fuel flow supply *** a result,the optimized gains in runway might not be suitable for other flight *** order to maintain the optimal control performance,the GTE controller gains should be adjusted according to the flight *** paper extends the application of the LLGA method to other flight conditions and then simulates a complete flight mission with different gains and weather condition *** this purpose,the control parameters in the Simulink model of the GTE controller are first corrected by the weather condition in ***,a typical flight mission is defined and divided into different flight segments based on the altitude and Mach number *** representative point is selected from each segment as the datum point for optimization *** this step,the LLGA method is used to find the best gains combinations for different flight conditions and the differences in optimization effects for different flight conditions are analyzed *** simulation results show that the optimization effect of the control performance of each flight condition is dependent on the value of(θδ)~(1/2)and the optimal K_(pla)in some flight conditions is approximately equal to p hd times of the Kplavalue in sea level standard ***,the complete flight mission is simulated with different gains and weather condition *** simulation results show that the engine performance has been greatly improved after optimization by LLGA in the transient state and the high altitude *** other steady states,the optimization effect is not

关键词： aeroengine control Control optimization flight condition flight mission simulation GA GTE LLGA Min-Max controller Robustness

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Science China(Technological Sciences) 2019年第3期62卷 490-501页

作者： YUE Ting ZHANG Qi YIN HaiPeng WANG LiXin ZHU JiangHui School of aeronautic Science and engineering Beihang University China flight test Establishment

The flight control law design for tanker should ensure that the closed-loop response can meet the aerial refueling mission requirements. In order to reveal the movement characteristics of the tanker and the handling characteristics of the pilot in aerial refueling, the flight path capture and hold under gust disturbance task is designed as the demonstration maneuver mission to evaluate the flying qualities for tanker in aerial refueling task, which is based on the design requirements of maneuvering tasks used in mission-oriented flying qualities assessment. By analyzing the flight path tracking and holding requirements of the tanker in aerial refueling mission, the relevant parameters that reflect the response characteristics of the tanker in pitch and roll axes are put forward. The ground flight simulation test based on mission-oriented flight quality assessment is conducted, and the test pilot's assessment results based on Cooper-Harper rating and PIO scales are obtained for different flight control law configurations. The suggested requirements of the closed-loop response characteristics of the pitch and roll axes of the tanker are put forward, which can be specifications for the aerial refueling mode flight control design of tanker.

关键词： aerial refueling tanker closed-loop response flight simulation test mission-oriented

Design of MC9 test Equipment for Inertial Reference System

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International Journal of Plant engineering and Management 2024年第2期29卷 115-128页

作者： ZHANG Haowen GUAN Hongyang WANG Shuangjia AVIC Xi′an flight Automatic Control Research Institute Xi′an 710076China

Inertial reference system is one of the airborne *** to the requirements of SAE ARP4754A Guidelines for Development of Civil Aircraft and Systems,MC9 equipment qualification test is needed to verify that the inertial reference system can perform reservation function under specified service *** is,the inertial reference system shall pass certain environmental tests specified in DO⁃*** tests are faced with the problem that the test equipment should have the function requirements of isolation protection and load ***,a kind of test equipment which can provide isolation protection and simulate load function in the test is designed.

关键词： inertial reference system MC9 isolation protection simulated load

Mshpy23:a user-friendly,parameterized model of magnetosheath conditions

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Earth and Planetary Physics 2024年第1期8卷 89-104页

作者： Jaewoong Jung Hyunju Connor Andrew Dimmock Steve Sembay Andrew Read Jan Soucek NASA Goddard Space flight Center GreenbeltMDUSA Department of Astronomy University of MarylandCollege ParkMDUSA Swedish Institude of Space Physics UppsalaSweden University of Leicester LeicesterUK Institute of Atmospheric Physics Academy of Sciences of the Czech Republic

Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind−Magnetosphere−Ionosphere Link Explorer(SMILE)will observe magnetosheath and its boundary motion in soft X-rays for understanding magnetopause reconnection modes under various solar wind conditions after their respective launches in 2024 and *** conditions,namely,plasma density,velocity,and temperature,are key parameters for predicting and analyzing soft X-ray images from the LEXI and SMILE *** developed a userfriendly model of magnetosheath that parameterizes number density,velocity,temperature,and magnetic field by utilizing the global Magnetohydrodynamics(MHD)model as well as the pre-existing gas-dynamic and analytic *** this parameterized magnetosheath model,scientists can easily reconstruct expected soft X-ray images and utilize them for analysis of observed images of LEXI and SMILE without simulating the complicated global magnetosphere ***,we created an MHD-based magnetosheath model by running a total of 14 OpenGGCM global MHD simulations under 7 solar wind densities(1,5,10,15,20,25,and 30 cm)and 2 interplanetary magnetic field Bz components(±4 nT),and then parameterizing the results in new magnetosheath *** compared the magnetosheath model result with THEMIS statistical data and it showed good agreement with a weighted Pearson correlation coefficient greater than 0.77,especially for plasma density and plasma ***,we compiled a suite of magnetosheath models incorporating previous magnetosheath models(gas-dynamic,analytic),and did two case studies to test the *** MHD-based model was comparable to or better than the previous models while providing self-consistency among the magnetosheath ***,we constructed a tool to calculate a soft X-ray image from any given vantage point,which can support the planning and data analysis of the aforementioned LEXI and SMILE missions.A release of the code has been uploaded to a Git

关键词： magnetosheath python modeling

Modified robust optimal adaptive control for flight environment simulation system with heat transfer uncertainty

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Chinese Journal of aeronautics 2021年第2期34卷 420-431页

作者： Meiyin ZHU Xi WANG Xitong PEI Song ZHANG Zhihong DAN Nannan GU Shubo YANG Keqiang MIAO Huairong CHEN Jiashuai LIU School of Energy and Power engineering Beihang UniversityBeijing 100083China Collaborative Innovation Center for Advanced aero engine Bejing 100083China Science and Technology on Altitude Simulation Laboratory AECC(Aero Engine Corporation of China)Sichuan Gas Turbine EstablishmentMianyang 621000China

To solve the rapid transient control problem of flight Environment Simulation System(FESS) of Altitude Ground test Facilities(AGTF) with large heat transfer uncertainty and disturbance, a new adaptive control structure of modified robust optimal adaptive control is *** mathematic modeling of FESS is given and the influence of heat transfer is analyzed through energy view. To consider the influence of heat transfer in controller design, we introduce a matched uncertainty that represents heat transfer influence in the linearized system of FESS. Based on this linear system, we deduce the design of modified robust optimal adaptive control law in a general way. Meanwhile, the robust stability of the modified robust optimal adaptive control law is proved through using Lyapunov stability theory. Then, a typical aero-engine test condition with Mach Dash and Zoom-Climb is used to verify the effectiveness of the devised adaptive controller. The simulation results show that the designed controller has servo tracking and disturbance rejection performance under heat transfer uncertainty and disturbance;the relative steady-state and dynamic errors of pressure and temperature are both smaller than 1% and 0.2% respectively. Furthermore,the influence of the modification parameter c is analyzed through simulation. Finally, comparing with the standard ideal model reference adaptive controller, the modified robust optimal adaptive controller obviously provides better control performance than the ideal model reference adaptive controller does.

关键词： Altitude ground test facilities flight environment simulation system Heat transfer Model reference adaptive control Optimal control modification Uncertainty