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Adaptive PI Control Based Stability Margin Configuration of aircraft Control Systems with Unknown System Parameters and Time Delay

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Journal of Systems Science & Complexity 2024年第4期37卷 1507-1525页

作者： ZHANG Zhibing ZHOU Dapeng WANG Yeguang GAO Wanxin ZHANG Yanjun avic shenyang aircraft design and research institute Shenyang 110035China School of Automation Beijing Institute of TechnologyBeijing 100081China State Key Lab of Autonomous Intelligent Unmanned Systems Beijing Institute of TechnologyBeijing 100081China

The stability margin is a vital indicator for assessing the safety level of aircraft control *** should maintain sufficient stability margin to ensure safety during flight,especially in the process of large maneuver *** stability margin is generally quantified by the Bode diagram,which strictly depends on the system parameters and the open-loop transfer ***,due to the uncertain flight environments,transmission delays of sensors and mode switchings,etc.,there exist large parameter and structure uncertainties in the aircraft control systems,which make it difficult to precisely configure the stability margin to the desired value by the usual control *** address this problem,an indirect adaptive control strategy is proposed in this paper,where an adaptive PI control law with the capability of self-configuration of stability margin is *** developed control law not only achieves stable time-varying command tracking in the time domain,but also is able to automatically configure the phase margin and gain margin in the frequency ***,the simulation of the one-degree-of-freedom roll rate control model of the air vehicle verifies the validity of the proposed control method.

关键词： Adaptive control aircraft control parameter uncertainty stability margin configuration

Tube-based robust reinforcement learning for autonomous maneuver decision for UCAVs

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Chinese Journal of Aeronautics 2024年第7期37卷 391-405页

作者： Lixin WANG Sizhuang ZHENG Haiyin PIAO Changqian LU Ting YUE Hailiang LIU School of Aeronautical Science and Engineering Beihang UniversityBeijing 100191China shenyang aircraft design&research institute Shenyang 110035China

Reinforcement Learning(RL)algorithms enhance intelligence of air combat AutonomousManeuver Decision(AMD)policy,but they may underperform in target combat environmentswith *** enhance the robustness of the AMD strategy learned by RL,thisstudy proposes a Tube-based Robust RL(TRRL)***,this study introduces a tube todescribe reachable trajectories under disturbances,formulates a method for calculating tubes basedon sum-of-squares programming,and proposes the TRRL algorithm that enhances robustness byutilizing tube size as a quantitative ***,this study introduces offline techniques forregressing the tube size function and establishing a tube library before policy learning,aiming toeliminate complex online tube solving and reduce the computational burden during ***,an analysis of the tube library demonstrates that the mitigated AMD strategy achievesgreater robustness,as smaller tube sizes correspond to more cautious *** finding highlightsthat TRRL enhances robustness by promoting a conservative *** effectively balanceaggressiveness and robustness,the proposed TRRL algorithm introduces a“laziness factor”as aweight of ***,combat simulations in an environment with disturbances confirm thatthe AMD policy learned by the TRRL algorithm exhibits superior air combat performance comparedto selected robust RL baselines.

关键词： Air combat Autonomous maneuver decision Robust reinforcement learning Tube-based algorithm Combat simulation

Fabrication of Bio-inspired Superamphiphobic Aluminum Alloy Surface with Oil-triggered Wenzel-Slippery Transition via Femtosecond Laser

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Journal of Bionic Engineering 2024年第3期21卷 1375-1387页

作者： Weijian Liu Feng Guan Fulin Zhang Chenrui Wang Wei Zheng Lu Zhai Zhaohua Lin Chunbao Liu avic shenyang aircraft Corporation Shenyang110000China School of Mechanical and Aerospace Engineering Jilin UniversityChangchun130022China

Surface-tension-confined microfluidic devices are platforms for manipulating 2D droplets based on patterned surfaces with special *** have great potential for various applications,but are still in the early stages of development and face some challenges that need to be *** study,inspired by the Wenzel and slippery transition of rose petal,develops a Patterned Oil-triggered Wenzel-slippery Surface(POWS)to examine the microfluidic devices.A laser-chemical composite method is established to fabricate POWSs,which take rose-petal-like microstructures as wettability pattern and a superamphiphobic surface as the *** prepared POWSs switched between high adhesion superhydrophobic state and the slippery liquid-infused surface state through adding or removing the lubricant *** the high adhesion superhydrophobic state,the droplets can be sticked on the *** the slippery liquid-infused state,the droplet can slide along the wettability pattern as the designed route.A POWS-based droplet reactor is further constructed,on which,the droplets can be remotely controlled to move,mix and react,as *** a POWS,which manipulates droplets with surface tension controlled by the switchable wettability patterns,would be a promising candidate to construct multiple surface-tension-confined microfluidic *** addition,the fabrication technique and design principle proposed here may aid the development of various field related to the bio-inspired surfaces,such as water collection,desalination and high throughput analysis,etc.

关键词： Biomaterials Bio-inspired surface Oil-triggered wenzel-slippery transition Superhydrophobicity Femtosecondlaser

Drogue detection for autonomous aerial refueling via hybrid pigeon-inspired optimized color opponent and saliency aggregation

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Chinese Journal of Aeronautics 2024年第5期37卷 27-38页

作者： Tongyan WU Haibin DUAN Yanming FAN State Key Laboratory of Virtual Reality Technology and Systems School of Automation Science and Electrical EngineeringBeihang UniversityBeijing 100083China Virtual Reality Fundamental research Laboratory Department of Mathematics and TheoriesPeng Cheng LaboratoryShenzhen 518000China avic shenyang aircraft design and research institute Shenyang 110035China

Drogue detection is one of the challenging tasks in autonomous aerial refueling due to the requirement for accuracy and *** detection based on image intrinsic cues can achieve fast detection,but with poor *** studies reveal that optimization-based methods provide accurate and quick solutions for saliency *** paper presents a hybrid pigeon-inspired optimization method,the optimized color opponent,that aims to adjust the weight of color opponent channels to detect the drogue *** can optimize the weights in the selected aerial refueling scene offline,and the results are applied for drogue detection in the scene.A novel algorithm aggregated by the optimized color opponent and robust background detection is presented to provide better precision and *** results on benchmark datasets and aerial refueling images show that the proposed method successfully extracts the saliency region or drogue and exhibits superior performance against the other saliency detection methods with intrinsic *** algorithm designed in this paper is competent for the drogue detection task of autonomous aerial refueling.

关键词： Autonomous aerial refueling Drones Hybrid pigeon-inspired optimization Color opponent Saliency detection Saliency aggregation

Hierarchical Reinforcement Learning Adversarial Algorithm Against Opponent with Fixed Offensive Strategy

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Journal of Shanghai Jiaotong university(Science) 2024年第3期29卷 471-479页

作者：赵英策张广浩邢正宇李建勋 shenyang aircraft design and research institute Shenyang 110031China School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Based on option-critic algorithm,a new adversarial algorithm named deterministic policy network with option architecture is proposed to improve agent's performance against opponent with fixed offensive *** option network is introduced in upper level design,which can generate activated signal from defensive and of-fensive strategies according to temporary *** the lower level executive layer can figure out interactive action with guidance of activated signal,and the value of both activated signal and interactive action is evaluated by critic structure *** method could release requirement of semi Markov decision process effectively and eventually simplified network structure by eliminating termination possibility *** to the result of experiment,it is proved that new algorithm switches strategy style between offensive and defensive ones neatly and acquires more reward from environment than classical deep deterministic policy gradient algorithm does.

关键词： hierarchical reinforcement learning fixed offensive strategy option architecture deterministic gradi-entpolicy

Biomimetic porous silicon oxycarbide ceramics with improved specific strength and efficient thermal insulation

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Journal of Materials Science & Technology 2024年第1期168卷 185-193页

作者： Zhuoqing Zhang Jinghan Li Lei Cao Yu Shi Huajie Yang Rui Yang Fan Xie Xing Zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159China shenyang aircraft design and research institute Shenyang 110035China

Considering the challenge of aerodynamic heating,the development of high-performance insulating ce-ramic materials with lightweight and low thermal conductivity is crucially important for aerospace vehi-cles to achieve flight at high speed for a long *** this work,macro-porous silicon oxycarbide(SiOC)ceramics with directional pores(DP-SiOC)(mean pore size of 88.1μm)were prepared using polysiloxane precursors via freeze casting and photocrosslinking,followed by *** DP-SiOC samples were lightweight(density∼0.135 g cm^(-3))with a porosity of 90.4%,which showed good shapability through the molding of polysiloxane *** DP-SiOC samples also exhibited an ultra-low thermal con-ductivity of 0.048 W(m K)^(-1)at room temperature,which can also withstand heat treatment at 1200°C for 1 *** addition,scaffolds with triply periodic minimal surfaces(TPMS)were fabricated using digital light processing(DLP)printing,which was further filled with polysiloxane precursors for increasing the strength of *** TPMS scaffolds filled with macro-porous SiOC ceramics(TPMS-DP-SiOC)showed good integration between TPMS and macro-pore structures,which had a porosity∼75%and high specific strength of 9.73×10^(3)N m kg^(-1).The thermal conductivity of TPMS-DP-SiOC samples was 0.255 W(m K)^(-1)at room *** biomimetic TPMS-DP-SiOC ceramics developed in this study are likely used for thermal protection systems.

关键词： Thermal insulation Light weight Macro-porous ceramics SiOC

Comparison of nonlinear modeling methods for the composite rubber clamp

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 763-778页

作者： Yiming CAO Hui MA Xumin GUO Bingfeng ZHAO Hui LI Xin WANG Bing WANG School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems of Ministry of Education of China Northeastern UniversityShenyang 110819China avic shenyang Engine design institute Shenyang 110013China Dalian Mengyu Machinery Co. Ltd.Dalian 116317Liaoning ProvinceChina

The cubic stiffness force model(CSFM)and Bouc-Wen model(BWM)are introduced and compared *** unknown coefficients of the nonlinear models are identified by the genetic algorithm combined with *** fitting the identified nonlinear coefficients under different excitation amplitudes,the nonlinear vibration responses of the system are *** results show that the accuracy of the BWM is higher than that of the CSFM,especially in the non-resonant ***,the optimization time of the BWM is longer than that of the CSFM.

关键词： pipeline system nonlinear clamp model composite rubber clamp amplitude-dependent characteristic vibration response experiment

Knowledge and data jointly driven aeroengine gas path performance assessment method

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Chinese Journal of Aeronautics 2024年第5期37卷 533-557页

作者： Zhe WANG Xuyun FU Rui ZHANG Zhengfeng BAI Xiangzhao XIA Wei JIANG Department of Mechanical Engineering Harbin Institute of TechnologyWeihai 264209China Weihai Key Laboratory of Intelligent Operation and Maintenance Harbin Institute of TechnologyWeihai 264209China Control System design Laboratory AECC ShenYang Engine Research InstituteShenyang 110015China

Aeroengines,as the sole power source for aircraft,play a vital role in ensuring flight *** gas path,which represents the fundamental pathway for airflow within an aeroengine,directly impacts the aeroengine's performance,fuel efficiency,and ***,timely and accurate evaluation of gas path performance is of paramount *** paper proposes a knowledge and data jointly driven aeroengine gas path performance assessment method,combining Fingerprint and gas path parameter deviation ***,Fingerprint is used to correct gas path parameter deviation values,eliminating parameter shifts caused by non-component performance ***,coarse errors are removed using the Romanovsky criterion for short-term data divided by an equal-length overlapping sliding ***,an Ensemble Empirical Mode Decomposition and Non-Local Means(EEMD-NLM)filtering method is designed to“clean”data noise,completing the preprocessing for gas path parameter deviation ***,based on the characteristics of gas path parameter deviation values,a Dynamic Temporary Blended Network(DTBN)model is built to extract its temporal features,cascaded with Multi-Layer Perceptron(MLP),and combined with Fingerprint to construct a Dynamic Temporary Blended AutoEncoder(DTB-AutoEncoder).Eventually,by training this improved autoencoder,the aeroengine gas path multi-component performance assessment model is formed,which can sufficiently decouple the nonlinear mapping relationship between aeroengine gas path multi-component performance degradation and gas path parameter deviation values,thereby achieving the performance assessment of engine gas path *** practical application cases,the effectiveness of this model in assessing the aeroengine gas path multi-component performance is verified.

关键词： Performance assessment Aeroengine Fingerprint Gas path parameter deviation values Jointly drive

Study of Flow and Heat Transfer in an Ejector-Driven Swirl Anti-Icing Chamber

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Fluid Dynamics & Materials Processing 2024年第5期20卷 989-1014页

作者： Yi Tu Yuan Wu Yu Zeng Hunan University of Arts and Sciences Hunan Key Laboratory of Distributed Electric Propulsion Vehicle Control TechnologyChangde415000China Liaoning Provincial Key Laboratory of aircraft Ice Protection AVIC Aerodynamics Research InstituteShenyang110034China School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China

The formation of ice on the leading edge of aircraft engines is a serious issue,as it can have catastrophic *** Swirl Anti-Icing(SAI)system,driven by ejection,circulates hot fluid within a 360°annular chamber to heat the engine inlet lip surface and prevent *** study employs a validated Computational Fluid Dynamics(CFD)approach to study the impact of key geometric parameters of this system on flow and heat transfer characteristics within the anti-icing ***,the entropy generation rate and exergy efficiency are analyzed to assess the energy utilization in the *** research findings indicate that,within the considered flow range,reducing the nozzle specific areaφfrom 0.03061 to 0.01083 can enhance the ejection coefficient by over 60.7%.This enhancement increases the air circulating rate,thereby intensifying convective heat transfer within the SAI ***,the reduction inφalso leads to a significant increase in the required bleed air pressure and a higher entropy generation rate,indicating lower exergy *** nozzle angleθnotably affects the distribution of hot and cold spots on the lip surface of the SAI ***θfrom 0°to 20°reduces the maximum temperature difference on the anti-icing chamber surface by 60 K.

关键词： Swirl anti-icing heat transfer exergy efficiency hot and cold spot aircraft engine