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Parameter Effects of the Potential‑Field‑Driven Model Predictive Controller for Shared Control

Automotive Innovation 2023年第1期6卷 48-61页

作者： Mingjun Li Chao Jiang Xiaolin Song Haotian Cao State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China

Parameter effects of the potential-field-driven model predictive control(PF-MPC)method on performances of shared control systems during obstacles avoidance are *** PF-MPC controllers of autonomous driving and shared control systems are designed based on the constructed potential fields and model predictive control method,and the driver-vehicle dynamics and the driver-related costs are also considered in the design of the shared *** explore a potential approach of alleviating driver-automation conflicts of the shared control systems,different motion planning results generated by the PF-MPC controller are explored by adjusting effects of potential fields’parameters,which provides possibilities to decrease driver-automation conflicts between the planned trajectory and driver’s target ***,two case studies are designed to discuss different frameworks and parameters effects on shared control *** show that the proposed shared control frameworks considering driver-vehicle dynamics and the driver-related cost show better performances regarding driver-automation conflicts management and driving safety than the decentralized control *** the longitudinal normalized constant of potential fields parameters shows influences on the driver-automation conflicts management and driving safety performances of shared control.

关键词： PF-MPC method Potential field Parameter effect Driver-automation conflict

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A modified maxwell-pulse thermoplastic constitutive model of in-situ Ta-particle reinforced Zr-based bulk metallic glass composites

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Progress in Natural Science:Materials International 2024年第4期34卷 753-766页

作者： Pan Gong Zhuang Wang Guoqing Yu Maojun Li Xin Zhuo Xuefeng Tang Mao Zhang Lei Deng Junsong Jin A.A.Churakova Xinyun Wang State Key Laboratory of Materials Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle Hunan University Institute of Molecule and Crystal Physics Ufa Federal Research Center RAS

The impact of different Ta contents on the mechanical properties and thermoplastic forming ability of in-situ Taparticle reinforced Zr–Cu–Al–Ni bulk metallic glass composites was studied. The composition(Zr55Cu30Al10-Ni5)94Ta6with the best comprehensive performance was chose for a systematic investigation into its thermoplastic behavior in the supercooled liquid region（SLR）, with quantitative analysis conducted by the strain rate sensitivity index and activation volume. The steady-state flow stress and the stress overshoot intensity were augmented with deformation temperature decreasing, strain rate increasing, and the addition of the secondary phase, leading to a transition from Newtonian to non-Newtonian flow regime. The addition of the secondary phase deteriorated the rheological properties of the material. To solve the problem that the Maxwell-Pulse constitutive model showed an inability to accurately describe the steady-state flow process. A modified constitutive relationship, introducing the effect of the volume fraction of Ta particles on viscosity and elastic modulus in the steady-state flow process which was ignored in Maxwell-pulse model, was established. The fitting results of the true stress-strain curves of the modified Maxwell-pulse constitutive model were in better agreement with the experimental date than those of the Maxwell-pulse constitutive model, with higher prediction accuracy. The modified constitutive model well predicted the thermoplastic deformation behavior of(Zr55Cu30Al10Ni5)*** influence mechanism of Ta particles on the flow behavior was explained that Ta particles increased the viscosity of amorphous matrix, thereby hindering its flow and ultimately leading to an increase in flow stress.

关键词： Bulk metallic glass composites Supercooled liquid region Thermoplastic deformation Constitutive model Influence mechanism

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Elastic three-dimensional phononic topological insulators with Dirac hierarchy

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 54-62页

作者： Shao-Yong Huo Qiu-Shuang Yang Jiu-Jiu Chen Hong-Kang Li Long-Chao Yao Fu-Chun He Chun-Ming Fu College of Mechanical Engineering University of South ChinaHengyang 421001China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China

Three-dimensional(3D)phononic topological insulators(TIs)featuring two-dimensional(2D)surface states and one-dimensional(1D)hinge states have opened up a new route for multi-dimensional robust wave transport,providing unprecedented methods for integrated acoustic sensors and energy harvesting ***,aiming at the elastic 3D phononic TI with gapless surface states and hinge states,the realization of elastic 3D phononic TIs with gapless surface states and hinge states is a significant challenge due to the complicated multi-mode polarization of elastic waves in 3D *** this study,we demonstrate an elastic 3D phononic TI with a Dirac hierarchy by elaborately operating the corresponding spatial symmetries of the chiral honeycomb ***,a 3D double Dirac cone of elastic wave can be achieved by doubling the lattice along the outof-plane direction to fold two iso-frequency Weyl *** topological phase transitions and 2D gapless two-fold Dirac surface states of elastic wave are realized by breaking the half-lattice spatial translation ***,based on the Brillouin zone folding along the in-plane direction,the 2D gapless two-fold surface Dirac cones are folded into four-fold surface Dirac ***,by inducing the relative radius of adjacent holes to break the in-plane spatial inversion symmetry,the fourfold surface Dirac cones are gapped and associated with a surface state inversion,in which the gapless 1D hinge Dirac dispersion is *** research offers a route for engineering the hierarchies of TIs in 3D elastic wave systems and provides new possibilities for designing 3D ultrasonic devices with unconventional functions.

关键词： Dirac topological hierarchy

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Sound quality prediction of unsteady vehicle interior sound

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International Journal of vehicle Noise and Vibration 2023年第1-2期19卷 55-66页

作者： Xie, Xiaoping Wen, ZhiJie State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha410082 China

In this paper, the noise samples of pure electric vehicles under unsteady-state are collected. Then, the subjective evaluation test is carried out after pre-processing such as screening and intercepting. The subjective sound quality scores of the noise samples are obtained. Meanwhile, the noise samples are calculated of four conventional psychoacoustic objective parameters such as loudness, sharpness, roughness, and speech intelligibility. Preprocessing by ensemble empirical mode decomposition (EEMD) is performed. Characteristic parameters of noise samples such as time-frequency domain fractal dimension difference and sample entropy of noise samples are obtained based on fractal dimension and sample entropy theory. Finally, the quality prediction model of vehicle interior sound is established based on six characteristic parameters and BP neural network. The results show that the prediction effect is excellent for the subjective scores of sound quality of unsteady interior sound in the vehicle. © 2023 Inderscience Enterprises Ltd.

关键词： Empirical mode decomposition

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Developing Mechanical Metamaterials Under an Adaptable Topology Optimization design Framework

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Acta Mechanica Solida Sinica 2023年第2期36卷 306-316页

作者： Zhengtong Han Kai Wei Xiaoyang Liu Yuhang Long Jialong Li Xinglin Chen State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083China

Developing mechanical metamaterials through topology optimization attracts high attention in both computational design and engineering ***,most of the studies in the literature are of quite limited applicability and poor ***,this work originally established an adaptable metamaterial topology optimization framework through integrating a commercial finite element analysis(FEA)***,the sensitivity analysis was derived and simplified to avoid the complex extraction of internal FEA information according to the strain-energy-based homogenization method.A series of two-and three-dimensional metamaterials with different properties,i.e.,bulk and shear moduli,negative Poisson’s ratio,were subsequently *** optimized metamaterials were fabricated and experimentally tested based on the additive manufacturing,firmly demonstrating the effectiveness of the developed design *** well-structured design framework can be conveniently extended to the systematic design of metamaterials with various other exclusive performances,fulfilling the urgent need for metamaterial design methods.

关键词： Metamaterial Topology optimization Mechanical properties Tensile experiments

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Trajectory tracking control of autonomous heavy-duty mining dump trucks with uncertain dynamic characteristics

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Science China(Information Sciences) 2023年第10期66卷 246-262页

作者： Liang CHEN Zhaobo QIN Manjiang HU Hongbo GAO Yougang BIAN Biao XU Xiaoyan PENG State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Wuxi Intelligent Control Research Institute of Hunan University Department of Automation University of Science and Technology of China

The proportion of mines using autonomous mining trucks is still very low at present. To promote the development of intelligent mining, it is urgent to proceed with the drive-by-wire modification to common mining trucks and design a motion control algorithm considering uncertain dynamic *** paper proposes a trajectory tracking control method for autonomous heavy-duty mining dump trucks(AHMDTs) with uncertain dynamic characteristics. In this method, a driving/braking force compensation algorithm based on an inverse dynamic model is designed to guarantee accurate longitudinal control with less control gain tuning. Using road curvatures, a modified rear-wheel position feedback control method is proposed to deal with reverse-path tracking, which can simultaneously reduce the lateral error and yaw angle error. A modified Stanley controller considering the collaborative preview based on speed and curvature is constructed to achieve accurate path tracking in the forward gear. Moreover, the proposed method focuses on the practice of trajectory tracking control in an open-pit mine condition with the adverse effects caused by uncertain vehicle dynamics, huge variable load, and large actuator lag. Real vehicle tests show that the proposed methodology can control AHMDTs with a low tracking error.

关键词： vehicle control trajectory tracking control driving/braking force compensation rear-wheel position feedback

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Anisotropy reduction and mechanical property improvement of additively manufactured stainless steel based on cyclic phase transformation

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Journal of Materials Science & technology 2024年第17期184卷 1-14页

作者： Bochuan Li Kang Xu Chao Jiang State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China Automotive Engineering Research Institute Byd Auto Industry Company LimitedShenzhen 518000China

Owing to the special layer-by-layer deposition process of directed energy deposition(DED),columnar coarse grains,produced by cyclic reheating with intrinsic directional heat flow along the building direc-tion,are difficult to *** grains result in strong anisotropic characteristics with poor mechanical properties,which restrict the application of DED *** work proposes a novel fabrication strat-egy based on the cyclic-phase-transformation behavior,which can reduce the anisotropy and improve the mechanical properties of DED-printed stainless *** this fabrication strategy,316 L powder(austenitic stainless steel)and 17-4PH powder(martensitic stainless steel)were mixed in different mass ratios to fabricate five types of DED-printed stainless *** the five samples,P70(mixture of 70 wt%17-4PH powder and 30 wt%316 L powder)showed the weakest anisotropy and the best mechanical properties,which can be attributed to the cyclic phase transformation under cyclic reheating treatment and the transformation-induced plasticity(TRIP)effect over a wide range of strains,***-pared with the pure 316 L printed material,the tensile test results of P70 showed that the yield strength(YS)and ultimate tensile strength(UTS)increased by 35.4%and 34.5%,respectively,whereas the uniform elongation(UE)and total elongation(TE)were improved by 63.9%and 31.4%,*** addition,the strength-ductility balance(UTS×UE)increased by as much as 120.4%.The proposed fabrication strategy is expected to reduce the anisotropy in other materials that undergo cyclic-phase-transformation phe-nomena during additive manufacturing.

关键词： Directed energy deposition Anisotropy reduction Cyclic phase transformation Mechanical properties

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A study of boundary conditions for pedestrian thorax impact test

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International Journal of vehicle Systems Modelling and Testing 2024年第2期18卷 120-133页

作者： Long, Yongcheng Liu, Yu Xiao, Yu Ruan, Zhisheng Xiao, Zhi Zhang, Guanjun Huang, Jing State Key Laboratory of Intelligent Vehicle Safety Technology Chongqing401122 China China Automotive Engineering Research Institute Co. Ltd. Chongqing401122 China Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle Hunan University Changsha410082 China

Thorax injury is one of the main injuries during pedestrian impacts, and it is important to determine the boundary conditions for pedestrian thorax impactor tests. A series of virtual cases were built up to simulate the vehicle-pedestrian impact accidents. Then, the kinematic process was analysed during the vehicle-pedestrian impacts, and thorax impact parameters were extracted. Finally, the statistical characteristics of these impact parameters were obtained for thorax impactor tests. The results show that vehicle type affects the pedestrian impact kinematics and thorax impact parameters significantly. The range of thorax wrap-around distance is 928~1915 mm and 1018~1762 mm during sedan-pedestrian impact and SUV-pedestrian impact respectively. The average thorax impact speeds are about 5.8 m/s and 4.8 m/s in sedan-pedestrian impact and in SUV-pedestrian impact respectively. The average thorax impact velocity angles are 26.8° and 19.5° respectively. These results can provide the effective reference data for pedestrian thorax impactor tests. Copyright © 2024 Inderscience Enterprises Ltd.

关键词： Kinematics

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High-precision numerical modeling of the pro jectile launch and failure mechanism analysis of pro jectile-borne components

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Applied Mathematics and Mechanics(English Edition) 2025年第5期46卷 885-906页

作者： Xindan GUO Qiming LIU Xu HAN Tao LI Bin’an JIANG Canwei CAI State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China State Key Laboratory of Reliability and Intelligence of Electrical Equipment School of Mechanical EngineeringHebei University of TechnologyTianjin 300401China Artillery Ammunition Technology Laboratory PLA Army Academy of Artillery and Air DefenseHefei 230031China

As core components of precision-guided projectiles,projectile-borne components are highly susceptible to failure or even damage in complex high-overload environments,thereby significantly compromising launch reliability and ***,accurately characterizing the mechanical behavior of propellants remains challenging due to the limitations in the current internal ballistic theory and the constraints of large-scale artillery firing *** complicates the high-precision numerical modeling of projectile launch,and obstructs investigations into the failure mechanisms of projectile-borne ***,this paper identifies propellant parameters using the computational inverse method under uncertainty,further establishes high-precision numerical models of projectile launch,and explores the failure mechanisms of projectile-borne components in complex high-overload ***,a projectile launching experiment is meticulously designed and executed to obtain the breech pressure and muzzle ***,a general simulation model is built,and the powder burn model is used to simulate the ignition and ***,the propellant parameters are effectively identified with the computational inverse method by the combination of the experiments and simulations.A high-precision numerical model of projectile launch is modified with the parameters validated by another experiment,and the high-overload characteristics during projectile launch are thoroughly analyzed based on this ***,the high-overload characteristics of projectile-borne components are analyzed to elucidate the stress variation laws and to reveal the failure mechanisms influenced by time and spatial *** research provides an effective method for perfectly identifying propellant parameters and building high-precision numerical models of projectile ***,it provides significant guidance for the anti-high overload design and analysis of projectile-bo

关键词： projectile-borne component high-overload environment propellant parameter identification computational inverse technique failure mechanism

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Flexible Transparent Electrochemical Energy Conversion and Storage: From Electrode Structures to Integrated Applications

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Energy & Environmental Materials 2023年第1期6卷 43-71页

作者： Yanli Zhao Huaizhi Liu Yu Yan Tianwei Chen Huihuang Yu Lucky Ogheneakpobo Ejeta Guanhua Zhang Huigao Duan National Engineering Research Center for High-Efficiency Grinding State Key Laboratory of Advanced Design and Manufacturing for Vehicle BodyCollege of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China

The rapid progress of flexible electronics tremendously stimulates the urgent demands for the matching power supply systems. Flexible transparent electrochemical energy conversion and storage devices (FT–EECSDs), with endurable mechanical flexibility, outstanding optical transmittance, excellent electrochemical performance, and additional intelligent functions, are considered as preferable energy supplies for future self-powered flexible electronic systems. A comprehensive review of the reasonable design of flexible transparent electrode and recent progress on the FT–EECSDs is presented herein. The manufacturing techniques of generally classified three types of flexible transparent electrodes are systematically summarized. Emphasis is given to the recent developments in the transparent solid-state electrolyte, flexible transparent energy conversion, and storage devices. The standard evaluation methods and reasonable evaluation parameters to evaluate the flexibility and transparency of FT–EECSDs are highlighted. Additionally, the typical integrated applications of FT–EECSDs are also described. Finally, the current challenges and a future perspective on the research and development direction are further outlined.

关键词： electrochemical energy conversion and storage flexible electronics flexibletransparent elect

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