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Science China Technological Sciences 2025年

作者： Junyu HU Yourui TAO Shanhu LI Xu HAN College of Mechanical and vehicle engineering Hunan University State key laboratory of reliability and Intelligence of Electrical Equipment Hebei University of Technology

To enhance the tip positioning accuracy and robustness against disturbances of linear colocated motion systems, a novel composite feedforward (COMFF) control with Bi-Loop iterative feedforward tuning (IFFT) is proposed. The tip positioning error consists of the coupled tip residual vibration and linear motor tracking error. Given the influence of nonlinear friction and load flexibility, the topology of COMFF is designed as decoupled structures so that COMFF can suppress the tip residual vibration and compensate for the linear motor tracking error compatibly. Furthermore, Bi-Loop IFFT is built to improve the robustness of COMFF in high-precision motor tracking performance. In the state space of the linear motor tracking error based on the projection theorem, two loops are performed in parallel along the iteration direction. One is the P-type iteration loop that drives linear motor tracking errors to converge to the zero state. The other is the observation loop constructed by the recursive least square with forgetting factors to accelerate the P-type iteration loop. Driven by the P-type iteration loop with the aid of the observation loop, the proposed COMFF is integrated with fast convergence and high robustness when confronted with model disturbances. The effectiveness of the proposed COMFF combined with Bi-Loop IFFT is validated by experiments.

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A decoupled method for time-dependent reliability-based design optimization

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Science China Technological Sciences 2025年第1期 312-324页

作者： Dequan ZHANG Meide YANG Xu HAN State key laboratory of reliability and Intelligence of Electrical Equipment School of Mechanical EngineeringHebei University of Technology State key laboratory of Advanced Design and Manufacturing for vehicle Body College of Mechanical and Vehicle EngineeringHunan University

Time-dependent reliability-based design optimization(TRBDO) has received extensive attention because of its ability to achieve optimal solutions that help meet the requirement for whole lifecycle reliability by quantitatively considering dynamic uncertainties. However, directly solving TRBDO problems is computationally expensive, if not prohibitive, owing to the need to repeatedly evaluate time-dependent probabilistic constraints. To address this challenge, an efficient decoupled method called sequential optimization and time-dependent reliability assessment(SOTRA) is proposed in this study. This method transforms the original TRBDO problem, initially formulated probabilistically, into a problem using percentile formulation after discretizing time-dependent performance functions. By adopting the equivalent minimum performance target point(EMPTP) concept, the TRBDO problem is further converted into an equivalent deterministic optimization problem, which is subsequently solved through a sequential iteration process involving deterministic optimization and time-dependent reliability analysis. To efficiently and robustly search an EMPTP for reliability analysis, a time-dependent self-adaptive finite-step length method is developed. To verify the proposed SOTRA method against existing TRBDO methods, a numerical example, a benchmark structural design case of a simply supported beam, and an engineering application for flexible wheel design are exemplified in this study. The results demonstrate that the proposed SOTRA method exhibits high efficiency and robustness in solving TRBDO problems.

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Design and parametric optimization of thermal management of lithium-ion battery module with reciprocating air-flow

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Journal of Central South University 2015年第10期22卷 3970-3976页

作者：刘燕平欧阳陈志江清柏梁波 School of Automobile and Mechanic engineering Changsha University of Science and Technology key laboratory of Safety Design and reliability technology for engineering vehicle (Changsha University of Science and technology) key laboratory of lightweight and reliability technology for engineering vehicle of Hunan Province (Changsha University of Science and technology)

Single cell temperature difference of lithium-ion battery(LIB) module will significantly affect the safety and cycle life of the battery. The reciprocating air-flow module created by a periodic reversal of the air flow was investigated in an effort to mitigate the inherent temperature gradient problem of the conventional battery system with a unidirectional coolant flow with computational fluid dynamics(CFD). Orthogonal experiment and optimization design method based on computational fluid dynamics virtual experiments were developed. A set of optimized design factors for the cooling of reciprocating air flow of LIB thermal management was determined. The simulation experiments show that the reciprocating flow can achieve good heat dissipation, reduce the temperature difference, improve the temperature homogeneity and effectively lower the maximal temperature of the modular battery. The reciprocating flow improves the safety, long-term performance and life span of LIB.

关键词： lithium-ion battery thermal management reciprocating air-flow temperature difference orthogonal optimization simulation

New method for controlling minimum length scales of real and void phase materials in topology optimization

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Acta Mechanica Sinica 2020年第4期36卷 805-826页

作者： Xuanpei Rong Jianhua Rong Shengning Zhao Fangyi Li Jijun Yi Luo Peng School of Automotive and Mechanical engineering Changsha University of Science and TechnologyChangsha 410076Peopled Republic of China State key laboratory of Advanced Design and Manufacturing for vehicle Body Hunan UniversityChangsha 410082People’s Republic of China key laboratory of lightweight and reliability technology for engineering vehicle of Hunan Province dhangsha University of Science and TechnologyChangsha 410114Peopled Republic of China

Minimum length scale control on real and void material phases in topology optimization is an important topic of research with direct implications on numerical stability and solution *** it also is a challenge area of research due to serious conflicts of both the solid and the void phase element densities in phase mixing domains of the topologies obtained by existing ***,there is few work dealing with controlling distinct minimum feature length scales of real and void phase materials used in topology designs.A new method for solving the minimum length scale controlling problem of real and void material phases,is ***,we introduce two sets of coordinating design variable filters for these two material phases,and two distinct smooth Heaviside projection functions to destroy the serious conflicts in the existing methods(*** Comput Methods Appl Mech Eng 199(14):123-135,2009).Then,by introducing an adaptive weighted 2-norm aggregation constraint function,we construct a coordinating topology optimization model to ensure distinct minimum length scale controls of real and void phase materials for the minimum compliance *** adopting a varied volume constraint limit scheme,this coordinating topology optimization model is transferred into a series of coordinating topology optimization sub-models so that the structural topology configuration can stably and smoothly changes during an optimization *** structural topology optimization sub-models are solved by the method of moving asymptotes(MMA).Then,the proposed method is extended to the compliant mechanism design *** examples are given to demonstrate that the proposed method is effective and can obtain a good 0/1 distribution final topology.

关键词： Structural topology optimization Minimum length scale Manufacturability Coordinating density filter Heaviside projections Void phase

Modeling tactile perceived intensity for vibration from a coin eccentric rotating mass motor

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Science China Technological Sciences 2025年

作者： Yun FANG Jingchen HUANG Yujun WU Jiaqi DONG Weichao GUO Xinjun SHENG State key laboratory of Mechanical System and Vibration School of Mechanical Engineering Shanghai Jiao Tong University Meta Robotics Institute Shanghai Jiao Tong University

Establishing the relationship between vibrotactile parameters and perceived intensity（PI） is of great significance in the regulation of desired sensations, which contribute to haptic interfaces in practical applications. Coin eccentric rotating mass（ERM） motors are routinely utilized due to their lightweight design and efficient ability to evoke strong tactile sensations. By adjusting input voltages, ERMs can yield different stimuli, but the effects of their physical properties on PI remain ***, we developed the physical model of the ERM-skin system and optimized the parameters affecting PI. Moreover, the relationship between stimulus and perception was derived based on Fechner?s law. Three experiments were conducted on fifteen subjects（ten males and five females, aged 24.40 ± 2.87 years） to identify the vibration parameters and corresponding PI to verify the proposed PI model. ERMs in this study were attached to phantom skin/forearm with slim adhesive tape to minimize the interference. Experiment 1 performed vibration calibration with ERM attached to the skin phantom to simulate the actual configuration. Then, the relative and absolute PI of subjects on specific stimuli were acquired in Experiments 2 and *** fitting reliability of the proposed PI model was evaluated on fifteen subjects with R2of 0.73 ± 0.07 and root mean squared error（RMSE） of 1.35 ± 0.28. Overall, the proposed PI model established the quantitative relationship between stimulus parameters（vibration parameters and physical parameters） and subjective PI, which provided theoretical support for ERM optimization and vibrotactile modulation.

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Corrosion evolution and behaviour of Al-2.1Mg-1.6Si alloy in chloride media

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Rare Metals 2021年第4期40卷 908-919页

作者： Ya-Ya Zheng Bing-Hui Luo Chuan He Yang Gao Zhen-Hai Bai College of Materials Science and engineering Central South UniversityChangsha 410083China key laboratory of Safety Design and reliability technology for engineering vehicle Changsha University of Science and TechnologyChangsha 410114China

Owing to the importance of finding better methods and technologies for protecting against corrosion of aluminium alloys,research into the electrochemical characteristics of the corrosion is an ongoing *** this paper,the corrosion behaviour of Al-Mg-Si alloys in 3.5 wt% NaCl solution was investigated using multiple methods,including scanning electron microscopy(SEM),transmission electron microscopy(TEM),potentiodynamic polarisation measurement and electrochemical impedance spectroscopy(EIS).The results suggest that corrosion begins with dealloying of Mg,followed by conversion of MgSi particles into Al-Fe-Mn-Si *** corrosion rate increased until it reached a peak and then *** increase in the corrosion rate may be attributed to an increased electrochemical driving force,which is produced by anodic dissolution between the matrix and residual MgSi ***,the thin re-deposited layer of inert elements also plays an important role in accelerating the anodic process of the corrosion *** passivated corrosion pit and narrowed intergranular corrosion(IGC)pathway cause the area of active dissolution to decrease,thus reducing the corrosion rate.

关键词： Al-Mg-Si alloys Corrosion behaviour Electrochemical Corrosion rate IGC corrosion pathway

Capacity models on expressway near a bus bay stop with an access

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Journal of Central South University 2015年第8期22卷 3239-3246页

作者：张洪宾孙小端贺玉龙宇仁德 Beijing key laboratory of Traffic engineering Beijing University of Technology School of Transportation and vehicle engineering Shandong University of Technology

To determinate the expressway capacity near a bus bay stop with an access, capacity models on the expressway near a bus stop with an access were developed on the basis of gap acceptance theory and queuing theory. Depending on a bus stop position to an entrance or an exit ramp, the capacity models were developed for four cases. Bus bay stops with overflow and bus bay stops without overflow were considered. A comparison of simulation experiment and model calculation was carried out. Results show that the suggested models have high accuracy and reliability, at bus arrival rate below 60 vehicles per hour(veh/h) or vehicle volumes at the entrance and the exit below 200 passenger cars units per hour(pcu/h), and there are no significant difference in the capacities for four cases. When bus arrival rate is above 240 veh/h, the capacities of all four cases will decline rapidly. With berth number increasing, the increasing of the capacities is no obvious for four cases. As the bus arrival rate and vehicle volumes at the entrance and the exit increase, bus stops located downstream of an entrance and upstream of an exit have a remarkably effect on the capacities. The latter case is much heavier than the former. Those results can be used to traffic design and optimization on urban expressway near a bus stop with an access.

关键词： capacity public transport entrance and exit traffic flow theory delay

Hybrid deep neural network based prediction method for unsteady flows with moving boundary

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Acta Mechanica Sinica 2021年第10期37卷 1557-1566,I0003页

作者： Ren-Kun Han Zhong Zhang Yi-Xing Wang Zi-Yang Liu Yang Zhang Gang Chen State key laboratory for Strength and Vibration of Mechanical Structures Shannxi Key Laboratory for Environment and Control of Flight VehicleSchool of Aerospace EngineeringXi’an Jiaotong UniversityXi’an710049China Science and technology on reliability and Environment engineering laboratory Beijing Institute of Structure and Environment EngineeringBeijing100076China

Any motion, forced or free, of boundary affects the flow field around this boundary. A new kind of reduced order model (ROM) based on hybrid deep neural network is proposed to model flow field evolution process of unsteady flow around moving boundary. This hybrid deep neural network can map the relationship between the flow field at the next time step and the flow field and boundary positions at the previous time steps. Based on the learned information, the hybrid deep neural network can quickly and accurately predict the flow field. Unsteady flows around forced oscillation cylinder with various amplitudes, frequencies, and Reynolds numbers are simulated to establish the training and testing datasets. The prediction results of the hybrid deep neural network and the computational fluid dynamics (CFD) simulation results are consistent with high accuracy. The forces on the moving boundary can be integrated through the predicted flow field data. Good performance makes this new ROM method can be used in many fluid dynamics research fields, which needs fast and accurate simulation.

关键词： Deep neural network Flow fields prediction Moving boundary

Study on the Driving Style Adaptive vehicle Longitudinal Control Strategy

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IEEE/CAA Journal of Automatica Sinica 2020年第4期7卷 1107-1115页

作者： Jing Huang Yimin Chen Xiaoyan Peng Lin Hu Dongpu Cao the State key laboratory of Advanced Design and Manufacturing for vehicle Body Hunan UniversityChangsha 410082China the Department of Mechanical and Mechatronics engineering University of WaterlooWaterlooON N2L3G1Canada the College of Mechanical&vehicle engineering Hunan UniversityChangsha 410082China the School of Automotive and Mechanical engineering and Hunan Province Key Laboratory of Safety Design and Reliability Technology for Engineering VehicleChangsha University of Science and TechnologyChangsha 410114China

This paper presents a fusion control strategy of adaptive cruise control(ACC) and collision avoidance(CA),which takes into account a driver’s behavioral style. First, a questionnaire survey was performed to identify driver type, and the corresponding driving behavioral data were collected via driving simulator experiments, which served as the template data for the online identification of driver type. Then, the driveradaptive ACC/CA fusion control strategy was designed, and its effect was verified by virtual experiments. The results indicate that the proposed control strategy could achieve the fusion control of ACC and CA successfully and improve driver adaptability and comfort.

关键词： Adaptive cruise control collision avoidance driving simulator experiment driving style fusion control

Methods for Calculating Intervals of Reconstructed Results in Traffic Accidents with Different Types of Interval Traces

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Journal of Shanghai Jiaotong university(Science) 2017年第5期22卷 555-561页

作者：邹铁方李华李岳林蔡铭肖璟 School of Automobile and Mechanical engineering Changsha University of Science and Technology Hunan Province key laboratory of Safety Design and reliability technology for engineering vehicle Changsha University of Science and Technology School of engineering Sun Yat-sen University

In order to obtain more effective uncertainty analysis methods for analyzing uncertainty of a reconstructed result in a traffic accident with different types of interval traces, three new methods are proposed. The first method is named as sub-interval perturbed method, it is used for calculating the binary interval of the reconstructed result in an accident with binary interval traces, and it can overcome the interval extension problem well. The second method is based on interval arithmetic and the first method, it is used for calculating the ternary interval of the accident reconstruction result in an accident with ternary interval traces, and the most probable value of the reconstructed result is a number. The basic idea of the third method is the same as that of the second method, it is used for calculating the ternary interval of the accident reconstruction result in an accident with mixed interval traces, and the most probable value of the reconstructed result is an interval. All methods are demonstrated and validated by numerical cases. The results show that all methods are feasible and practical. Finally, a true vehicle-motorcycle accident is given, in which the braking distance of vehicle, and the throw distances of driver and motorcycle are all binary interval traces. The accident is reconstructed by the software PC-Crash, and the interval of impact velocity is analyzed. The interval of the velocity is [55.7, 64.3] km/h. This interval result is more objective than a single number. © 2017, Shanghai Jiaotong University and Springer-Verlag GmbH Germany.

关键词： Bins Highway accidents Motorcycles Numerical methods Uncertainty analysis