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Impulsive thrust strategy for orbital pursuit-evasion games based on impulse-like constraint

Chinese Journal of Aeronautics 2025年第1期38卷 520-536页

作者： Hongbo WANG Yao ZHANG Hao LIU Kunpeng ZHANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Space Intelligent Control Beijing Institute of Control EngineeringBeijing 100094China

This paper proposes a novel impulsive thrust strategy guided by optimal continuous thrust strategy to address two-player orbital pursuit-evasion game under impulsive thrust *** strategy seeks to enhance the interpretability of impulsive thrust strategy by integrating it within the framework of differential game in traditional continuous ***,this paper introduces an impulse-like constraint,with periodical changes in thrust amplitude,to characterize the impulsive thrust ***,the game with the impulse-like constraint is converted into the two-point boundary value problem,which is solved by the combined shooting and deep learning method proposed in this *** learning and numerical optimization are employed to obtain the guesses for unknown terminal adjoint variables and the game terminal ***,the accurate values are solved by the shooting method to yield the optimal continuous thrust strategy with the impulse-like ***,the shooting method is iteratively employed at each impulse decision moment to derive the impulsive thrust strategy guided by the optimal continuous thrust *** examples demonstrate the convergence of the combined shooting and deep learning method,even if the strongly nonlinear impulse-like constraint is *** effect of the impulsive thrust strategy guided by the optimal continuous thrust strategy is also discussed.

关键词： Orbital pursuit-evasion game Differential game Impulsive thrust Deep learning Shooting method

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Review on the Fabrication of Surface Functional Structures for Enhancing Bioactivity of Titanium and Titanium Alloy Implants

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Chinese Journal of Mechanical engineering 2024年第4期37卷 23-49页

作者： Heng Tang Jiaxiang Xu Bin Guo Yansong Xie Yalong Sun Yanjun Lu Yong Tang Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518000China School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou 450001China

Titanium and its alloys have been widely applied in many biomedical fields because of its excellent mechanical properties,corrosion resistance and good ***,problems such as rejection,shedding and infection will occur after titanium alloy implantation due to the low biological activity of titanium alloy *** structures with specific functions,which can enhance osseointegration and antibacterial properties,are fabricated on the surface of titanium implants to improve the biological activity between the titanium implants and human *** paper presents a comprehensive review of recent developments and applications of surface functional structure in titanium and titanium alloy *** applications of surface functional structure on different titanium and titanium alloy implants are introduced,and their manufacturing technologies are summarized and ***,the fabrication of various surface functional structures used for titanium and titanium alloy implants is reviewed and analyzed in ***,the challenges affecting the development of surface functional structures applied in titanium and titanium alloy implants are outlined,and recommendations for future research are presented.

关键词： Surface functional structure Titanium implant Manufacturing technology Bioactivity

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Study on Dry Electrical Discharge Assisted Grinding of SiCp/Al Composite

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Chinese Journal of Mechanical engineering 2025年第1期38卷 106-118页

作者： Yanjun Lu Yuming Huang Xiaobu Liu Rong Cheng Shunda Zhan Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518060China School of Intelligent Manufacturing and Equipment Shenzhen Institute of Information TechnologyShenzhen 518172China

SiC-reinforced aluminum matrix(SiCp/Al)composite is widely utilized in the aerospace,automotive,and electronics industries due to the combination of ceramic hardness and metal ***,the significant disparity in properties between SiC particles and the aluminum matrix results in severe tool wear and diminished surface quality during conventional *** study proposes an environmentally friendly and clean dry electrical discharge assisted grinding process as an efficient and low-damage machining method for SiCp/*** experimental platform was set up to study the impact of grinding and discharge process parameters on surface *** study compared the chip formation mechanism and surface quality between dry electrical discharge assisted grinding and conventional grinding,revealing relationships between surface roughness,grinding force,grinding temperature,and related *** results indicate that the proposed grinding method leads to smaller chip sizes,lower grinding forces and temperatures,and an average reduction of 19.2%in surface roughness compared to conventional *** axial,tangential,and normal grinding forces were reduced by roughly 10.5%,37.8%,and 23.0%,*** optimized process parameters were determined to be N=2500 r/min,vf=30 mm/min,a=10μm,E=15 V,f=5000 Hz,dc=80%,resulting in a surface roughness of 0.161μm.

关键词： Dry electrical discharge assisted grinding SiCp/Al composite Surface quality Grinding force Grinding temperature

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Evolution of soil DOM during thermal remediation below 100℃:concentration,spectral characteristics and complexation ability

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Frontiers of Environmental Science & engineering 2024年第8期18卷 31-41页

作者： Wan Huang Ziren Wan Di Zheng Lifeng Cao Guanghe Li Fang Zhang State Key Joint Laboratory of Environment Simulation and Pollution Control State Environment Protection Key Laboratory of Microorganism Application and Risk ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China National Engineering Laboratory for Site Remediation Technologies Beijing 100015China

The impact of thermal remediation on soil function has drawn increasing *** far,as the most active fraction of soil organic matter,the evolution of dissolved organic matter(DOM)during the thermal remediation lacks in-depth investigation,especially for the temperatures value below 100℃.In this study,a series of soil thermal treatment experiments was conducted at 30,60,and 90℃ during a 90-d period,where soil DOM concentration increased with heating temperature and *** molecular weight,functional groups content and aromaticity of DOM all decreased during the thermal *** excitation-emission matrices(EEM)results suggested that humic acid-like substances transformed into fulvic acid-like substances(FIII/FV increased from 0.27 to 0.44)during the heating process,and five DOM components were further identified by *** change of DOM structures and components indicated the decline of DOM stability and hydrophilicity,and can potentially change the bioavailability and *** temperature also resulted in the decline of DOM complexation ability,which may be caused by the loss of binding sites due to the decrease of polar function groups,aromatic structures and hydrophilic *** study provides valuable information about the evolution of DOM during thermal remediation,which would potentially change the fate of metal ions and the effectiveness of the post-treatment technologies in the treated region.

关键词： Thermal remediation below 100℃ Heating temperature Soil DOM concentration DOM spectral characteristics Excitation-emission matrices(EEM) Complexation ability

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A promising application of bulk metallic glasses in torque sensor

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Science China(Technological Sciences) 2024年第8期67卷 2505-2514页

作者： LU WenHao MA Jiang WANG Chao LIU YanHui Institute of Physics Chinese Academy of SciencesBeijing 100190China Shenzhen Key Laboratory of High Performance Nontraditional Manufacturing College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518060China

Torque sensors are essential components of robotic joints. In the past, structure optimization of force-sensing elements has been the common approach to improve the performance of the torque sensors. In this work, we demonstrate a torque sensor with bulk metallic glasses as a force-sensing element. Compared with the sensors made of stainless steel and aluminum alloy, the use of bulk metallic glass as a force-sensing element significantly improves sensor sensitivity, linearity, repeatability, hysteresis, and measuring range. Our work not only opens up a new avenue for the application of bulk metallic glasses, but also provides opportunities for enhancing the performance of force/torque sensors through materials optimization.

关键词： bulk metallic glasses amorphous alloys force sensors

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On high-performance rotational energy harvesting with a novel cam-like dielectric elastomer generator

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Science China(Technological Sciences) 2023年第5期66卷 1317-1334页

作者： FANG ShiTong WANG ShuaiBo ZHANG GuoQing WANG Chen XU JunChen WANG ZhouZhou FENG AiJie QIAO ZiJian YURCHENKO Daniil LAI ZhiHui Shenzhen Key Laboratory of High-Performance Nontraditional Manufacturing College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen518060China Guangdong Key Laboratory of Electromagnetic Control and Intelligent Robots College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen518060China School of Mechanical Engineering and Mechanics Ningbo UniversityNingbo315211China Institute Sound and Vibration Research University of SouthamptonSouthamptonSO171BJUK

Rotational energy is a type of common energy source that can be harvested for supplying low-powered electronic *** paper proposes and investigates a novel cam-like dielectric elastomer generator(CDEG)for high-performance rotational energy harvesting.A mushroom-head clamp is designed to form a type of advanced conical dielectric elastomer membranes(DEMs).Moreover,a type of multi-protrusion cam mechanism is designed in the CDEG to effectively convert any external rotational excitation into a linear reciprocating motion,which can be further converted into electricity through the ***,the operating principle of the system under external rotational excitation is analyzed theoretically by deducing the deformation condition of the DEMs and the electrical output of the ***,the prototype is fabricated,and the rotational-to-linear motion conversion rule of its cam-like mechanism and the DEM capacitance calculation approach are *** experimental results show that adequate charging time and discharging time of the DEMs,which can be realized through the proposed cam-like mechanisms,are beneficial to the energy harvesting(EH)performance of the ***,with the validated theoretical model,numerical simulations are conducted to further study the system dynamics and the influences of important system parameters on the EH performance to provide a guideline for system ***,the genetic algorithm is adopted to obtain the optimal system parameters and the corresponding electrical output of the proposed CDEG,demonstrating its superior output power at ultralow rotational frequencies compared with other typical rotational energy harvesters in the literature.

关键词： rotational energy harvesting dielectric elastomer generator cam-like mechanism rotational-to-linear conversion theoretical model

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Autonomous relative optical navigation based on unified modeling of external systematic errors

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Chinese Journal of Aeronautics 2024年第3期37卷 282-289页

作者： Dayi WANG Bowen SUN Maodeng LI Jiaxing LI Haiyin ZHOU Beijing Institute of Spacecraft System Engineering Beijing 100191China College of Sciences National University of Defense TechnologyChangsha 410073China National Key Laboratory of Space Intelligent Control Beijing Institute of Control EngineeringBeijing 100191China

To solve the problem that external systematic errors of the optical camera cannot be fully estimated due to limited computing resources,a unified dimensionality reduction representation method for the external systematic errors of the optical camera is proposed,and autonomous relative optical navigation is *** camera translational and misalignment errors are converted into a three-dimensional rotation error,whose differential model can be established through specific attitude control and appropriate ***,the rotation error and the relative motion state are jointly estimated in an augmented Kalman filter *** with the traditional method that estimates the camera translational and misalignment errors,the proposed method reduces the computational complexity in that the estimated state dimension is ***,as demonstrated by numerical simulation,the estimation accuracy is improved significantly.

关键词： Unified model Systematic errors Optical navigation Observability analysis Calibration

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Improving aircraft nose wheel steering stability based on control continuation method

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Science China(Technological Sciences) 2025年第3期68卷 258-277页

作者： Qiaozhi YIN Dexu KONG Jiawei WANG Hong NIE Xiaohui WEI National Key Laboratory of Helicopter Aeromechanics Nanjing210016China State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing210016China Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing210016China AVIC Nanjing Engineering Institute of Aircraft Systems Nanjing211106China

Aircraft steering instability during the taxiing process sometimes occurs resulting from the unstable bifurcation phenomena of the nonlinear steering dynamic system,which may lead to severe *** this study,the control parameter design of an aircraft nose wheel steering control system based on the control continuation method is proposed to reduce the number of unstable bifurcation points and enlarge the system stable region area in a certain parameter ***,the aircraft turning performance can be improved ***,a nonlinear aircraft rollout dynamic model is constructed,and the aircraft ground steering bifurcation characteristics are obtained under the open-loop steering control ***,the bifurcation performances under three closed-loop nose wheel steering controllers based on the feedback control method are compared,and the control parameter of the quadratic nonlinear controller with a better bifurcation control effect is selected as a second bifurcation parameter to analyze the directional system stability via two-parameter bifurcation ***,the influence of a crosswind on the aircraft ground steering bifurcation performance is studied for various control parameter ***,the control effects of a traditional proportional-integral-derivative(PID)nose wheel steering control law and the designed feedback controller are compared and ***,a semi-physical experiment of the aircraft nose wheel steering system is carried out,and different control parameter values are selected for test verification,which can further verify the control effect of the designed nonlinear feedback *** results indicate that the feedback control method is unable to vary the system bifurcation types,but appropriate control parameter design can effectively shrink the system instability region and even eliminate the unstable Hopf bifurcation points under some specific working conditions,improving the aircraft ground turning stability re

关键词： aircraft taxiing dynamics and stability nose wheel steering control system control continuation steering bifurcation characteristics quadratic feedback control

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A Feature-Aided Multiple Model Algorithm for Maneuvering Target Tracking

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 566-568页

作者： Yiwei Tian Meiqin Liu Senlin Zhang Ronghao Zheng Shanling Dong College of Electrical Engineering Zhejiang University National Key Laboratory of Industrial Control Technology Zhejiang University IEEE National Key Laboratory of Human-Machine Hybrid Augmented Intelligence Xi’an Jiaotong University

Dear Editor,This letter deals with the tracking problem for non-cooperative maneuvering targets based on the underwater sensor networks. Considering the acoustic intensity feature of underwater targets, a feature-aide... 详细信息

关键词： underwater Aided letter

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The roles of microstructural anisotropy in tribo-corrosion performance of one certain laser cladding Fe-based alloy

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Friction 2023年第9期11卷 1673-1689页

作者： Weitao SUN Xuehong HUANG Jian ZHANG Bin WANG Xiaoliang LIU College of Mechatronics Engineering Binzhou UniversityBinzhou 256600China Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) Dalian University of TechnologyDalian 116085China College of Mechatronics Engineering Binzhou PolytechnicBinzhou 256600China

Because of the microstructural anisotropy for laser cladding materials,the tribo-corrosion performance can vary significantly with different *** this study,one certain Fe-based coating was fabricated by laser *** study the effects of anisotropy,three working surfaces(0°,45°,and 90°to the building direction)were machined from the laser cladding samples;as-cast samples with an approximately homogeneous structure were prepared as *** tribo-corrosion tests were conducted in a 3.5 wt%NaCl solution with varying normal loads(5,10,and 15 N).The results demonstrated that the 45°surface has superior friction stability,corrosion resistance,and wear *** was directly related to the crystal orientation and grain boundary *** addition,a refined microstructure may enhance tribo-corrosion properties by increasing deformation resistance and decreasing surface activity.

关键词： laser cladding anisotropy Fe-based tribo-corrosion performance

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