Most Download articles

Published in last 1 year| In last 2 years| In last 3 years| All| Most Downloaded in Recent Month | Most Downloaded in Recent Year|

Published in last 1 year

Please wait a minute...


For Selected: Download Citations EndNote Ris BibTeX Toggle Thumbnails

Select

Visual Detection of Subsurface Corrosions in Ferromagnetic Metal Plates Using Pulsed Eddy Current Based on Dual-sensor Differential Mechanism WANG Jin1, LI Yong1, SU Bingjie1, GAO Wenlong1, XIANG Yi1, 2, LIU Zhengshuai1, CHEN Zhenmao1 China Mechanical Engineering    2025, 36 (03): 381-390.   DOI: 10.3969/j.issn.1004-132X.2025.03.001 Abstract （376）      PDF（pc） （17686KB）（346）       Knowledge map    Save A pulse eddy current visual detection method was proposed based on a dual-sensor differential mechanism for subsurface corrosions in ferromagnetic metal plates. In this method, a dual-sensor differential probe was used to pick up the pulsed eddy current testing signals, and the slope of the logarithmic curve along the falling edge of the testing signals and the peak value of the normalized differential signals were extracted as signal features, which were used for visual detection of defects of different sizes. Through simulation and experimental research, the correlation laws between the proposed signal features and the sizes of defects were established, and it is verified that the dual-sensor differential probe has the advantages of reducing noise interference and improving the detection sensitivity compared with traditional single-sensor probes. In addition, a method was proposed to fuse the two signal features, and the results indicate that the defect images using fused signal features have a higher image signal-to-noise ratio. The research method proposed herein provides an effective and reliable solution for the visual detection of subsurface corrosions in ferromagnetic metal plates. Reference | Related Articles | Metrics | Comments（0）

Select

China Mechanical Engineering    2025, 36 (04): 1-.   Abstract （311）      PDF（pc） （293186KB）（227）       Knowledge map    Save Related Articles | Metrics | Comments（0）

Select

Design of Scale-changeable Pantograph Legs for Heavy-duty Robots SUO Zhe, LI Xiang, LIU Jianfeng, WANG Jixin China Mechanical Engineering    2025, 36 (02): 191-196.   DOI: 10.3969/j.issn.1004-132X.2025.02.001 Abstract （364）      PDF（pc） （7951KB）（195）       Knowledge map    Save The motion characteristics of the 2 DOF(degree-of-freedom) scale-changeable pantograph leg mechanisms were analyzed, different designs for scale change were compared. A scale-changeable pantograph leg with a nonlinear length adjustment mechanisms was proposed. The length of the thigh and shank link could be adjusted with a single driver according to the nonlinear proportion relation. Thus, the scale could be changed while preserving the pantograph mechanism properties. The scale-changeable pantograph leg may change the scale without disassembling, adjust the foot working space and the carrying capacity of the robots. Reference | Related Articles | Metrics | Comments（0）

Select

State-of-the-art and Trend of High Loading Capacity Plastic Gear Drives LIU Huaiju, LU Zehua, ZHU Caichao China Mechanical Engineering    2025, 36 (01): 2-17.   DOI: 10.3969/j.issn.1004-132X.2025.01.001 Abstract （506）      PDF（pc） （15004KB）（177）       Knowledge map    Save Focusing on the loading capacity and applications in power transmission of plastic gears, the failure modes and loading capacity under the current materials and technology levels were introduced. The strengthening measures for improving loading capacity of plastic gears were elaborated from the application of new materials, lubrication improvement, collaborative design, and so on. The applications and potential of plastic gears scenarios in power transmissions such as automobile engines, vehicle reducers, and aeroengine accessory gearboxes were introduced, which has important reference significance for promoting the development of high load plastic gear technology and applications. Reference | Related Articles | Metrics | Comments（0）

Select

Research Progresses for Machining Characteristics and Field-assisted Techniques of γ-TiAl Alloys FAN Tao1, 2, YAO Changfeng1, 2, TAN Liang1, 2, SHAN Chenwei１, ２, XIA Ziwen1, 2 China Mechanical Engineering    2025, 36 (04): 636-645.   DOI: 10.3969/j.issn.1004-132X.2025.04.001 Abstract （1736）      PDF（pc） （25364KB）（173）       Knowledge map    Save γ-TiAl alloys, due to their low density, high specific strength and excellent high-temperature oxidation resistance had broad application potentials in the aerospace fields. However, due to their high brittleness and low room-temperature plasticity, they were considered typical difficult-to-machine materials, with challenges such as high cutting forces, rapid tool wear and surface defects during the machining processes. In recent years, field-assisted machining technologies provided new solutions to these issues. The material properties, machining characteristics, and surface integrity of γ-TiAl alloys were systematically analyzed, with a focus on the research progresses of field-assisted machining technologies, including their applications in reducing cutting forces, extending tool life and improving surface quality. Additionally, the current research limitations and future development trends were sorted out, aiming to provide theoretical and technical references for the efficient machining of γ-TiAl alloys.  Reference | Related Articles | Metrics | Comments（0）

Select

Study on Absolute Linear Time-grid Displacement Sensors with  Multi-frequency Magnetic Field Coupling YANG Jisen1, 2, 3, YUAN Junsong1, 3, XIU Fu1, 3, LIU Jiacheng1, 3, ZHANG Xiaolong1, 3 China Mechanical Engineering    2025, 36 (05): 889-897.   DOI: 10.3969/j.issn.1004-132X.2025.05.001 Abstract （427）      PDF（pc） （8864KB）（170）       Knowledge map    Save Aiming at the problems of mutual crosstalk among magnetic fields affecting the measurement accuracy of the sensors and reducing the signal-to-noise ratio when the excitation frequency of two code channels of a dual-row planar magnetic field sensor was the same， a multi-frequency magnetic field coupled absolute linear time-grid displacement sensor design scheme was proposed， which achieved the solution to the problems of eliminating the crosstalk of the magnetic fields among the code channels while solving the absolute displacement. The sensor was divided into fixed scale and dynamic scale， both using double-layer alternating structure， fixed scale using two columns of incremental code channel combination， divided into fine and coarse machines， the pairs of poles of two rows of excitation coils were two integers of the reciprocal relation， the absolute displacement measurement was realized by using the pairs of poles within the displacement difference. Precision machine measurement channel and rough machine measurement channel were input  different frequencies of the excitation current signals at the same time，  the precision machine was input the 1 MHz high-frequency current signals， the high-frequency excitation current signals might effectively enhance the inductive signals， improve the signal-to-noise ratio of the electrical processing system. Through the method of outlier frequency reduction， the sensor resolution was improved， which effectively solved the problems that it were difficult to reconcile the signal-to-noise ratio enhancement of the signals by increasing the frequency of the excitation signals and the high resolution of the sensors. Theoretical validation and error analysis of the sensors were carried out through electromagnetic simulation analysis. Finally， the experimental platform was built to carry out prototype experiments， and the experimental results show that the absolute sensor structure with multi-frequency magnetic field coupling effectively eliminates the magnetic field crosstalk between the fine and coarse machines， and the signal-to-noise ratio of the sensors is improved， with measurement errors are less than ±17.34 μm in the measurement range of 140 mm.  Reference | Related Articles | Metrics | Comments（0）

Select

Research on Flexible Job-shop Scheduling Considering Constraints of Peak Power Constrained LI Yibing1, 2, CAO Yan1, GUO Jun1, 2, WANG Lei1, 2, LI Xixing3, SUN Libo4 China Mechanical Engineering    2025, 36 (02): 280-293.   DOI: 10.3969/j.issn.1004-132X.2025.02.011 Abstract （238）      PDF（pc） （12926KB）（150）       Knowledge map    Save Peak power constrained flexible job shop scheduling problem(PPCFJSP) model was established to address the challenges of increased work cycles and increased machine load in flexible job shop scheduling under the constraints of peak power in the workshops. The optimization objectives were to minimize the maximum completion time and the maximum machine loads, taking into account the constraints of peak power in the workshops. For better scheduling decisions, firstly, the problem was transformed into a Markov decision process, then, a scheduling framework combining offline training and online scheduling was designed for solving PPCFJSP. Secondly, a double dueling deep q-network based on priority experience replay(D3QNPER) algorithm was designed based on priority experience replay, and a ε- greedy descent strategy introducing noise was designed to improve the convergence speed of the algorithm, further enhance the solving ability and stability of the solution results. Finally, experimental and algorithmic comparative studies were conducted to verify the effectiveness of the model and algorithm. Reference | Related Articles | Metrics | Comments（0）

Select

Study on Low Wear Machining Method of High Volume Fraction SiCp/Al Composite Materials by ECM-mechanical Combined Machining Processes Method HE Bin, ZHOU Xingyu, LU Hongyu, ZHANG Junfei, DING Kai, LI Qilin, LEI Weining China Mechanical Engineering    2025, 36 (04): 753-759.   DOI: 10.3969/j.issn.1004-132X.2025.04.012 Abstract （295）      PDF（pc） （12862KB）（149）       Knowledge map    Save To improve the problems of tool wear, poor surface quality and low machining efficiency of aluminum-based silicon carbide（SiCp/Al) composites with high volume fraction under conventional machining, an ECM-mechanical combined machining method was proposed, and the ECM-mechanical combined machining experiments of 60% volume fraction SiCp/Al composites were carried out. The results show that SiC particles are exposed on the surfaces with the removal of aluminum matrix. There is a certain depth of transition zone between the surface of the workpiece and the matrix after ECM, the aluminum matrix in the transition zone is locally removed, and the binding force of SiC particles is reduced. When the diamond grinding rod is used for machining the transition zone, the aluminum matrix adhesion phenomenon is not observed, the diamond grinding rod has almost no wear, and the surface damages are obviously reduced. The machinability of high volume fraction SiCp/Al composites may be improved by ECM-mechanical machining processes. Reference | Related Articles | Metrics | Comments（0）

Select

Influences of Strain Rate on Plastic Deformations and Martensitic Transformation Behaviors of 304 Stainless Steels ZHAN Lihua1, 2, ZHAO Shuai1, YANG Youliang1, 2, CHANG Zhilong3 China Mechanical Engineering    2024, 35 (12): 2132-2138，2168.   DOI: 10.3969/j.issn.1004-132X.2024.12.005 Abstract （619）      PDF（pc） （5871KB）（146）       Knowledge map    Save To investigate the plastic deformation behaviors and martensitic transformation rules of 0.5 mm thick 304 stainless steels at room temperature, uniaxial tensile tests were conducted at five different strain rates of 0.000 67 s-1, 0.002 s-1, 0.01 s-1, 0.1 s-1 and 1.0 s-1, with subsequent X-ray diffraction(XRD) analysis for phase analysis. The results reveal a notable increase in yield strength with rising strain rate, indicating strain rate strengthening effects. Additionally, due to plastic work converting into heat during tensile processes, martensitic transformation was inhibited, resulting in a slight tensile strength reduction. Below a true strain of 0.27, work hardening rates decrease under varying strain rates. However, beyond this threshold true strain, significant secondary hardening occurs under low strain rates, which is attributed to the internal martensitic transformation.To address this phenomenon, the Olson-Cohen equation was integrated into the traditional Johnson-Cook model to characterize secondary hardening during tensile processes across different strain rates. The improved Johnson-Cook model achieves high accuracy in predicting rheological stress changes, with deviations of 3.23%, 3.42%, 4.13%, 4.09%, and 5.14% respectively compared to experimental values, effectively capturing the secondary hardening stage at various strain rates. Reference | Related Articles | Metrics | Comments（0）

Select

Research Progresses on Incremental EMF Technology for Thin-walled Components CHENG Xiao1, LI Rui2, ZOU Guisheng2, LIN Junfeng1, 3, YU Haiping1, 3 China Mechanical Engineering    2024, 35 (12): 2092-2105.   DOI: 10.3969/j.issn.1004-132X.2024.12.001 Abstract （856）      PDF（pc） （12617KB）（145）       Knowledge map    Save With the development of Chinas high-end manufacturing industries, the demands for thin-walled components in many industrial fields such as aerospace were increased dramatically. The high-speed forming characteristics, traditional EMF was successfully applied to the production of thin-walled components of some key lightweight materials. However, due to the limitations of forming coil and discharge equipment, it was difficult to process large-scale and complex structure parts. In the past decade, incremental EMF technology was developed and gradually applied to the large thin-wall components processing, where a large number of research results were emerged. On the basis of briefly describing the principle and characteristics of EMF technology, the existing incremental EMF technology was divided into two categories according to the processing form: incremental electromagnetic composite forming and incremental electromagnetic direct forming. The research status of each processes was expounded from the aspects of basic principle, technical scheme and application results. Thus the main problems existing in the incremental EMF technology were analyzed, then the future development prospects and research direction of the incremental EMF technology were prospected. Reference | Related Articles | Metrics | Comments（0）

Select

A Robot Stiffness Identification Method Considering Weakly Rigid Joint Transmission Chain Structures and Flexible Rod Structures GUO Wanjin1, 2, 3, 4, LI Ru1, WANG Libin1, HAO Qinlei1, CAO Chuqing2, ZHAO Lijun2, 4 China Mechanical Engineering    2025, 36 (05): 974-985.   DOI: 10.3969/j.issn.1004-132X.2025.05.009 Abstract （216）      PDF（pc） （7073KB）（141）       Knowledge map    Save To solve the stiffness identification problem for a 3T2R highly dexterous robot with weakly rigid joint transmission chain structures and flexible rod structures, a robot stiffness identification method was proposed. Firstly, the structural characteristics of the compact and cost-effective hybrid robot configuration design and the motion characteristics for adjusting the high dexterity of operational postures were analyzed. The robot Jacobian matrix was constructed, and the end deformation model of the robot was established to analyze the influences of weakly rigid joint transmission chain structures and flexible rod structures on the robot end deformations. Then, considering the effects of weakly rigid joint transmission chain structures and flexible rod structures, along with the robotic structural characteristics of weak rigidity and large deformation, robot joint stiffness identification was carried out，and the variable stiffness modeling was completed for the mobile joint 3. Experimental results indicate that the proposed method increases the stiffness of joints 3, joint 4 and 5 by 146.59%, 30.18% and 36.07% respectively, compared to conventional stiffness identification methods. The error rates between the measured and theoretical calculation values of the overall end deformations are in 4%~6% at six selected robot poses. The capability of the proposed robot stiffness identification method was verified. Reference | Related Articles | Metrics | Comments（0）

Select

Simulation and Experimental Study of Temperature for Polishing Aero-engine Blades with Abrasive Cloth Wheel#br# #br# XIAN Chao1, 3, XIN Hongmin2, 3, DAI Hui2, CHENG Qingsi2 China Mechanical Engineering    2025, 36 (04): 802-810.   DOI: 10.3969/j.issn.1004-132X.2025.04.017 Abstract （280）      PDF（pc） （9909KB）（138）       Knowledge map    Save ANSYS software was used to simulate the instantaneous temperature fields in the polishing processes with abrasive cloth wheel using a rectangular heat source loading method. The temperature distribution on the blade surfaces and along the blade thickness direction in the polishing processes was studied, and the influences of processing parameters on the polishing temperature was explored. The results show that as the polishing process progresses, the polishing temperature distribution gradually stabilizes. When the polishing temperature stabilizes, the temperature values of the machined parts of the blade at different depths tend to be consistent, while the temperature of the machining parts decreases continuously along the depth direction; the polishing temperature gradient gradually decreases from the contact area being machined to the machined area; the polishing temperature increases with the increase of spindle speed, the effects of feed speed on the polishing temperature are not significant and the polishing temperature is positively correlated with the tangential polishing forces; the deviation rates between the measured and the simulated temperature values are not more than 10%, indicating that the good consistency and high accuracy of the simulation. Reference | Related Articles | Metrics | Comments（0）

Select

Design of Jig and Fixture for Machining Precision Forged Blade Tenons of Aeroengine ZHANG Shen1, LIANG Jiawei2, WU Dongbo3, WANG Hui4, ZHAO Bing1, XU Lijun5, ZHOU Fen5 China Mechanical Engineering    2025, 36 (04): 703-714.   DOI: 10.3969/j.issn.1004-132X.2025.04.007 Abstract （1234）      PDF（pc） （9510KB）（137）       Knowledge map    Save Precision forged blades of aeroengine were a typical thin-walled parts with complex curved surface. When milling the blade tenons, it was difficult to locate and easy to produce deformations and vibrations. Aiming at the above problems, a design method of multi-point clamping fixture for precision forged blades was proposed, and a low stress hard clamping fixture was designed. Static analysis was used to optimize the clamping position, select the coping element materials and optimize the clamping method. The effectiveness of the fixture was tested by modal tests and vibration tests. The results show that the low-band amplitude of the system is reduced by 50%, the high-band amplitude by 75%, the first-order resonance frequency is increased from 210 Hz to 402 Hz, the damping ratio under the peak value is increased from 17.4% to 25.9%, the effective value of vibration displacement signals is reduced by 35%, and the machining error margin is reduced by 59%. Reference | Related Articles | Metrics | Comments（0）

Select

Precise Regulation of Differential Pressures at Port of Load-sensitive Multi-way Valves Based on ADRC Algorithm LEI Xingmao1, DING Haigang1, 2, WANG Simin3, YANG Chengcheng1, PANG Zhizhen1 China Mechanical Engineering    2025, 36 (05): 954-962，973.   DOI: 10.3969/j.issn.1004-132X.2025.05.007 Abstract （215）      PDF（pc） （9511KB）（136）       Knowledge map    Save  Load-sensitive multi-way valve was the core component for the hydraulic system of construction machinery， the pressure compensator was used to keep the differential pressure of the valve ports constant， but the differential pressure was susceptible to the spool opening and load changes， resulting in low accuracy of the main valve flow rate control.Therefore， a new type of load-sensitive multi-way valve differential pressure continuous control method was proposed， a proportional solenoid was used to push the spools of the compensator valves， and ADRC algorithm was used to control the proportional solenoid thrusts and realize the closed-loop control of differential pressures of the main valves， so as to accurately control the flow rate.Firstly， the working principle of the system was introduced and a mathematical model was established， then a simulation model was established based on AMESim-MATLAB joint simulation platform， and a test bench was built for experimental validation， the characteristics of the valve differential pressure maintenance and the main valve flow rate regulation were analyzed under the conditions of load changes and main valve opening degree changes. The results show that compared with the load changes， the changes of the main valve opening degree have a greater impact on the  differential pressures. A new type of valve port differential pressure control structure and method may accurately control the load-sensitive multi-way valve differential pressures， so as to achieve the effectiveness of precise control of the flow rate， and may actively regulate the differential pressures without changing the main valve opening degree， so as to achieve the flow rate for the further regulation. Reference | Related Articles | Metrics | Comments（0）

Select

Machine Learning and Finite Element Simulation and Experimentation for Springback Prediction of Al-Li Alloys HUI Shengmeng1, MAO Xiaobo4, ZHAN Lihua1, 2, 3 China Mechanical Engineering    2024, 35 (12): 2114-2121.   DOI: 10.3969/j.issn.1004-132X.2024.12.003 Abstract （486）      PDF（pc） （4522KB）（132）       Knowledge map    Save Creep aging tests were conducted on the 2195 Al-Li alloys under various stress conditions at temperatures of 180 ℃, 190 ℃, and 200 ℃ respectively. Constitutive equations were derived using MATLAB software and incorporated into the nonlinear finite element software MSC.Marc to build a finite element model for the creep aging forming of 2195 Al-Li alloy spade segments. The model utilized time, stress, and temperature as input parameters, with the springback radius being the critical output parameter. To enhance the accuracy and efficiency of predictions, a comparative analysis of various machine learning regression models was conducted, leading to the selection of the ridge regression model as the predictive tool, which facilitated the rapid and precise prediction of the springback radius under diverse processing conditions. The high predictive accuracy and practical utility of the model were validated through 1∶1 experimental verification, demonstrating a relative error of 0.9% between the experimental components springback profile and the target profile.  Reference | Related Articles | Metrics | Comments（0）

Select

Depth of Cut Control for Thin-walled Parts in Robotic Milling Based on FLADRC SHI Long, ZHOU Hexiang, LI Zhoulong China Mechanical Engineering    2025, 36 (04): 671-680.   DOI: 10.3969/j.issn.1004-132X.2025.04.003 Abstract （2186）      PDF（pc） （8675KB）（129）       Knowledge map    Save Weakly rigid large thin-walled parts had large deformations and vibrations during robotic thinning machining, which led to a degradation of the surface quality of the workpieces and difficulties in ensuring the accuracy of the remaining wall thickness. To this end, a VCM-driven follower support head was used for vibration and deformation suppression, and a FLADRC based control strategy was proposed for depth of cut of robotic milling thin-walled parts. In order to verify the effectiveness of the control strategy, the system control models were firstly established based on the MATLAB/Simulink simulation and experimental platform, and the simulation analysis was carried out, then experimental verification was carried out on the thin-walled parts robotic milling experiment platform. Both of the simulation and experimental results show that the depth-of-cut control strategy based on the follower support head may significantly suppress the vibrations and deformations during the machining processes of thin-walled parts and effectively ensure the accuracy of the remaining wall thickness. In addition, compared with the traditional fuzzy PID control, the FLADRC has a better control effectiveness and exhibits higher robustness in the presence of external disturbances. Reference | Related Articles | Metrics | Comments（0）

Select

Effects of Forced Positioning&Clamping on Geometric and Physical Assembly Performances for Composite Structures and Collaborative Guarantee Strategies GUO Feiyan1, ZHANG Yongliang2, LIU Jialiang1, ZHANG Hui2 China Mechanical Engineering    2025, 36 (04): 655-670.   DOI: 10.3969/j.issn.1004-132X.2025.04.002 Abstract （1621）      PDF（pc） （7015KB）（124）       Knowledge map    Save The large-size & thin-walled aviation composite structures had low forming accuracy and huge in-plane warping deformation. The accumulation of assembly errors, unexpected geometric gaps and shape deviations were prone to occur at the joining areas. In engineering, passive reduction actions, such as applying local clamping forces was usually applied, but uneven internal stress distribution and even internal damages would be occurred, which affected the mechanical performances of the structures in service directly. Firstly, the principle of forced positioning clamping was explained, and the affection on geometric accuracy and mechanical properties of weak rigid composite parts was analyzed. Secondly, starting from the analysis of two main aspects, i.e. optimization on forced clamping process parameters before assembly, and flexible positioning force&position adjustment of fixtures during assembly, five key technologies were solved with detailed technical solutions, i.e. setting forced assembly force limits, reduction of geometric gaps, prediction of stress/damage evolution, reverse optimization of forced clamping process parameters, and precise measurement of assembly stress&damage. Then the active control of shape&force coupling and macro & micro collaborative guarantee in the clamping processes for assembly performance, could be achieved. Finally, for the composite assembly structures, from the perspective of practical engineering applications, the future working focus towards high assembly quality and efficient, and low-cost assembly goals were proposed. Reference | Related Articles | Metrics | Comments（0）

Select

A Reliability Allocation Method Considering Distribution and Transmission Models for Mechanical Systems WANG Zhichao1, LIU Chao1, RAN Yan2, CHEN Yifan3, JIANG Dongxiang1, ZHANG Genbao2, 3 China Mechanical Engineering    2025, 36 (06): 1143-1150.   DOI: 10.3969/j.issn.1004-132X.2025.06.001 Abstract （283）      PDF（pc） （1184KB）（122）       Knowledge map    Save To address the problems of the allocation reliability of lower-level units being greater than that of the upper-level unit in the multi-layer structure reliability allocation of mechanical systems, a novel reliability allocation method was proposed. Firstly, the mechanical systems were divided into a system-function-motion-action(SFMA) hierarchy structure. Then, according to the hierarchy structure consisting of distribution and transmission models, the reliability allocation techniques were proposed by combining the minimum cost method and reliability function, and the reliability allocation models of the mechanical systems, function units, motion units, and sub-motion units were established from top to bottom. Finally, taking the gear grinding machine as an example, the feasibility and effectiveness of the proposed method were verified. Reference | Related Articles | Metrics | Comments（0）

Select

Ultrasonic Vibration Softening Johnson-Cook Modeling and Validation of Thin Tube Curling Experiments SONG Pengfei1, 2, CAO Miaoyan1, 2, FU Min1, 2, CUI Yashuo1, 2, LI Yunfeng1, 2, LIU Zheng1, 2 China Mechanical Engineering    2024, 35 (12): 2106-2113，2121.   DOI: 10.3969/j.issn.1004-132X.2024.12.002 Abstract （494）      PDF（pc） （6974KB）（120）       Knowledge map    Save In order to accurately describe the deformation behaviors of lightweight thin-walled components during ultrasonic vibration-assisted forming, ultrasonic vibration normal excitation-assisted uniaxial tensile experiments were carried out with TU1 oxygen-free copper and 316L stainless steel. Considering the ultrasonic vibration softening effects, an ultrasonic vibration Johnson-Cook model was developed by introducing a new ultrasonic softening function. A subroutine was developed and embedded into finite elements for simulation, and was validated by comparison with unidirectional tensile and curling experiments. The results show that the numerical model may effectively capture the ultrasonic vibrational softening behaviors of the materials with an average absolute percentage error as low as 0.97%. Although different materials have different sensitivities to ultrasonic vibration, the ultrasonic softening rates all follow an Allometricl functional relationship with the ultrasonic energy field density. Reference | Related Articles | Metrics | Comments（0）

Select

China Mechanical Engineering    2025, 36 (04): 0-.   Abstract （207）      PDF（pc） （369KB）（115）       Knowledge map    Save Related Articles | Metrics | Comments（0）

Select

Lightweight Design of Concrete Pump Truck Boom Pins Based on Multi-fidelity Surrogate Model LI Peng1, 2, 3, 4, LI Mengcong1, 4, XIAO Libo2, 3, WANG Yitang1, 4, SONG Xueguan1, 4, YANG Ling5 China Mechanical Engineering    2025, 36 (04): 821-829.   DOI: 10.3969/j.issn.1004-132X.2025.04.019 Abstract （290）      PDF（pc） （9820KB）（115）       Knowledge map    Save As a key connecting and supporting component in a concrete pump truck boom system, how to reduce the mass of the pin shafts was a noteworthy issue in boom design. A parameterized finite element model of the hollow dumbbell pin shafts was constructed based on control parameters. Then, a more accurate feature mapping based MFS(FM-MFS) model was established through the mutual disturbance of high and low fidelity models and the reasonable allocation of high and low fidelity data. Genetic algorithm was used for optimization to obtain the optimal design scheme for the hollow dumbbell pins based on this surrogate model, achieving a weight reduction of 36%. Through theoretical, simulation, and experimental verification, it is shown that the hollow dumbbell pin shafts constructed based on the optimal parameters of the surrogate model may achieve lightweight and material consumption savings while still ensuring the physical and mechanical properties, which provides data support and reference for further applications in the future.  Reference | Related Articles | Metrics | Comments（0）

Select

China Mechanical Engineering    2024, 35 (12): 1-.   Abstract （168）      PDF（pc） （246695KB）（111）       Knowledge map    Save Related Articles | Metrics | Comments（0）

Select

Thread Extension Stress Analysis of Bolts under Pre-tensioning Conditions GUAN Jiaoyue1, GAO Yuan1, AI Yanting1, TIAN Jing1, YAO Yudong2 China Mechanical Engineering    2025, 36 (05): 923-932.   DOI: 10.3969/j.issn.1004-132X.2025.05.004 Abstract （327）      PDF（pc） （7649KB）（110）       Knowledge map    Save  It was difficult to accurately determine the thread stresses on the bolts under pre-tensionsing conditions， which might lead to strength fracture and premature loosening of the threads， and the reliability of the bolt joints was compromised. Currently， the contact state of the thread surfaces was usually described by stresses under an absolute coordinate system. However， the simulated stress direction was at an angle to the actual thread surface. The analysis results were not intuitive. Therefore， a thread mathematical model was derived and the extended stress analysis method of thread contact surfaces was proposed. Then， the finite element model of bolt joints was established for the structural characteristics of bolts. And the accuracy of the model was verified by tests. Finally， the extended stress analysis method was applied to study the thread surface stress and the distribution characteristics of bolts. The results show that the maximum error between the simulated preload and the testing preload is only 5.78%, where the accuracy of the simulation model is demonstrated. The extension stress analysis method may reflect the continuity and monotonicity of the stress distribution on the thread surfaces, and the method also reflects the optimal preload. The decreasing rate of the stress on the same layer thread is inversely proportional to the stress. From the stress analysis， the reason why the stresses on the thread are mainly concentrated in the first three turns is illustrated. The thread extension stress analysis method proposed herein is more intuitive and accurate. The paper may provide theoretical support for the anti-loosening analysis and reliability analysis of bolts. Reference | Related Articles | Metrics | Comments（0）

Select

Research on Precision Control of Large Deployable Antennas Driven  by Fusion of Data and Model JIANG Donglei1, ZHAO Qiangqiang1, WU Tengfei1, MA Jia2, JIA Kang1, HONG Jun1 China Mechanical Engineering    2025, 36 (05): 898-910.   DOI: 10.3969/j.issn.1004-132X.2025.05.002 Abstract （300）      PDF（pc） （7097KB）（108）       Knowledge map    Save In order to improve the surface precision of large deployable planar antennas efficiently and accurately by adjusting the truss system, the surface precision prediction and accuracy verification were realized from two aspects of finite element simulation analysis and photogrammetry. According to the principle of mechanics of materials and temperature equivalence theory, the simulation model of plane antenna surface precision was constructed. A rapid measurement system of surface accuracy was established based on photogrammetry. The variable confidence Gaussian process model was established by combining the finite element simulation samples and the photogrammetry measured samples, and the precision was optimized and adjusted by Bayesian optimization. The accurate prediction and on-site rapid adjustment of large planar antenna precision were realized, which may provide simulation analysis model support for forward precision evaluation and inverse optimization adjustment of large planar antennas.  Reference | Related Articles | Metrics | Comments（0）

Select

China Mechanical Engineering    2024, 35 (12): 0-.   Abstract （160）      PDF（pc） （362KB）（100）       Knowledge map    Save Related Articles | Metrics | Comments（0）

Select

China Mechanical Engineering    2025, 36 (04): 882-887.   DOI: 10.3969/j.issn.1004-132X.2025.04.026 Abstract （244）      PDF（pc） （1444KB）（99）       Knowledge map    Save Reference | Related Articles | Metrics | Comments（0）

Select

Research on Pressure Stabilization for Loading Cylinders under Centrifu-gation Supergravity Environment Based on Experimental Tests Bingjing QIU, Muhua JIA, Yinqi LI, Liubin JI China Mechanical Engineering    2025, 36 (8): 1651-1657.   DOI: 10.3969/j.issn.1004-132X.2025.08.001 Abstract （238）   HTML （9）    PDF（pc） （2744KB）（99）       Knowledge map    Save To solve the problems of excessive pressure fluctuations in the simulation environment of high gravity centrifugal environment without an external oil source， the factors causing pressure fluctuations were analyzed， and experimental tests were conducted on each factor. Based on the analysis of each factor， an accumulator stabilization scheme was proposed， and the effects of accumulator working parameters， working pressure， and working medium parameters on stabilization performance were compared under different deformation conditions of specimens through supergravity experiments. The experimental test results show that within the temperature range of 36~42.5 ℃， the pressure fluctuation of oil caused by temperature changes is less than 4%. The deformation of the specimen is the main factor affecting pressure fluctuations， with a pressure fluctuation ratio of up to 47% caused by a deformation of 1 mm in the samples. The fluctuation ratio of the accumulator during pressure stabilization under supergravity is proportional to the working pressure and the deformation of the specimen. The use of two 300 mL gas volume accumulators may achieve the requirement of less than 10% internal pressure fluctuation of 20 MPa， which is consistent with theoretical calculations. The test provides technical support for controlling pressure fluctuations in high-temperature and high-pressure devices under supergravity environments. Table and Figures | Reference | Related Articles | Metrics | Comments（0）

Select

Construction of Assembly Information Model Based on Assembly Feature Automatic Extraction for STEP Models JIA Kang1, 2, TANG Jing1, 2, REN Dongxu1, 2, WANG Hao1, 2, ZHAO Qiangqiang1, 2, HONG Jun1, 2 China Mechanical Engineering    2025, 36 (01): 123-132.   DOI: 10.3969/j.issn.1004-132X.2025.01.013 Abstract （1671）      PDF（pc） （8528KB）（92）       Knowledge map    Save Assembly information modeling was the foundation of digital assembly and intelligent assembly. However, the manual interactive modeling was inefficient and prone to errors in assembly feature recognition and assembly feature fitting, which was difficult to meet the precise modeling needs of complex mechanical systems. Based on the assembly process information implied by a 3D assembly model, this paper used STEP model files as inputs to study the algorithms for automatic extraction of assembly features and recognition of fitting relationships focused on geometric information. Furthermore, an information reasoning algorithm was proposed for constructing an integrated assembly information model from the perspectives of assembly accuracy modeling and assembly sequence planning. Finally, the effectiveness of the proposed algorithms was demonstrated through the construction of assembly instance information models based on the developed system. Reference | Related Articles | Metrics | Comments（0）

Select

Numerical and Experimental Study on Effects of Rivet Crack on Mechanics Properties of Self-piercing Riveted Joints CHENG Aiguo1, WANG Chao1, YU Wanyuan2, HE Zhicheng1 China Mechanical Engineering    2025, 36 (02): 197-208.   DOI: 10.3969/j.issn.1004-132X.2025.02.002 Abstract （350）      PDF（pc） （22151KB）（87）       Knowledge map    Save The rivet cracks generated in joining high-strength steels using SPR were simulated through finite element model, and the effects of rivet crack depth, crack position, and crack quantity on the mechanics properties of steel-aluminum SPR joints were systematically investigated. Firstly, a 2D axisymmetric numerical model was established using LS-DYNA software to simulate the SPR processes, and the accuracy of the numerical model was validated by comparing experimental and simulated joint cross-profiles. Secondly, a 2D-3D finite element model generation method was employed to establish a 3D numerical model of SPR joints to simulate the mechanics properties of SPR joints. The fracture parameters of rivets were calibrated using LS-OPT software. The developed 3D numerical model of SPR joints could accurately predict the mechanics properties of SPR joints. The results of parametric study indicate that the mechanics properties of the SPR joints decrease with increasing crack depth and gradually increase as the external crack position moves downward, but the internal crack has minimal influence. When multiple cracks exist in the rivets, the mechanics properties of the joints depend on the weakest cracks and are independent of the quantity. Reference | Related Articles | Metrics | Comments（0）

Select

Chatter Identification Method for Heavy-duty Robotic Milling Systems Based on Variational Mode Filtering and Attention Mechanism LIANG Zhiqiang1, 2, CHEN Sichen1, DU Yuchao1, LIU Baolong1, 2, GAO Zirui1, YUE Yi3, XIAO Yubin4, ZHENG Haoran1, QIU Tianyang1, LIU Zhibing1 China Mechanical Engineering    2025, 36 (05): 1018-1027,1073.   DOI: 10.3969/j.issn.1004-132X.2025.05.013 Abstract （1193）      PDF（pc） （7393KB）（86）       Knowledge map    Save A method was proposed for identifying chatters in heavy-duty robotic milling systems by integrating variational mode filtering with fixed parameters, envelope filtering and an attention mechanism network identification. Initially, variational mode filtering theory was applied to eliminate non-chatter signal components in the high-frequency ranges by optimally selecting a quadratic penalty. Then, to swiftly identify the current machining conditions, the envelope filtering method was employed, leveraging signal time domain distribution and the frequency domain mapping law to remove the spindle speed-related signal components in the low-frequency ranges. Subsequently, a network identification model incorporating an attention mechanism was developed to identify preprocessed multi-temporal short-term signal segments for machining condition identification, followed by verification experiments on heavy-duty robotic milling systems. Experimental analysis results demonstrate that by eliminating non-chatter signals in the high-frequency ranges and spindle speed-related components in the low-frequency ranges, the accuracy of regenerative chatter identification is significantly enhanced, achieving an identification accuracy of 98.75%. Compared with alternative identification methods, the proposed method may effectively identify regenerative chatters during heavy-duty robotic milling processes, thus offering valuable technical support for future online chatter suppression of heavy-duty robotic milling. Reference | Related Articles | Metrics | Comments（0）

Select

A Cooperative Strategy for Pushing and Grasping Target Object in Cluttered Scenes Based on Deep Reinforcement Learning HU Kaixiong1, SONG Yuanhang1, ZHOU Yong1, LI Weidong2 China Mechanical Engineering    2025, 36 (01): 133-140.   DOI: 10.3969/j.issn.1004-132X.2025.01.014 Abstract （297）      PDF（pc） （10242KB）（84）       Knowledge map    Save To improve the success rate and efficiency of robotic grasping for occluded target objects in cluttered scenes, a collaborative push-grasp strategy was proposed based on deep reinforcement learning. The strategy employed 2 deep Q networks and used RGB-D images as inputs to determine push or grasp actions, which optimized object arrangement for better grasping conditions. A “grab-push-grab” three-stage training method was introduced in the model to enhance grasping capabilities significantly. An image morphology-based assessment method effectively identified and filtered low-quality grasp actions to increase successful rates and efficiency. Experimental results confirm that this method significantly enhances the successful rate and efficiency of grasping target objects. Reference | Related Articles | Metrics | Comments（0）

Select

Design and Experiments of Bonded-type Disc Stator M-DOF Ultrasonic Motors PAN Zhiyong, WANG Liang, JIN Jiamei, QIU Jianmin, FENG Haoren China Mechanical Engineering    2025, 36 (01): 38-46,58.   DOI: 10.3969/j.issn.1004-132X.2025.01.004 Abstract （353）      PDF（pc） （11970KB）（84）       Knowledge map    Save  In order to solve the problems such as low positioning accuracy, large structural dimensions, and difficulty in applying pre-pressure, which were commonly found in M-DOF ultrasonic motors, a novel bonded-type disc stator M-DOF ultrasonic motor was proposed. Firstly, finite element simulations were carried out to verify the working principles of the disc stator and determine the geometry. Then, the disk stator was fabricated and tested for the impedance characteristics and vibration characteristics. Finally, the prototype of the M-DOF ultrasonic motor was assembled, and the mechanics performance characteristics were evaluated experimentally. The experimental results show that both of the start/stop response time of the prototype are less than 20 ms, and the angular displacement resolutions are less than 30 μrad respectively. The prototype has the advantages such as rapid response and high positioning accuracy. Reference | Related Articles | Metrics | Comments（0）

Select

Hybrid Optimization for Housing Structure Stiffener and Support Location LI Jian1, DING Xiaohong1, ZHANG Yijie2, XIONG Min1, WANG Han1, ZHANG Heng1 China Mechanical Engineering    2025, 36 (01): 69-77.   DOI: 10.3969/j.issn.1004-132X.2025.01.007 Abstract （470）      PDF（pc） （9519KB）（84）       Knowledge map    Save The internal stiffener layout and support location of housing structure played an important role in improving of structural performance and lightweight. A design method for hybrid distribution optimization of stiffener and support locations of housing structures was proposed. Independent support elements and stiffener base structures were introduced to establish a mathematical model for the hybrid optimization of stiffener distribution and support location of the housing structure. The optimal design for stiffener distribution of the housing structure was performed by an adaptive growth method. The support location was optimized based on the bi-directional evolutionary structural optimization method. The results show that the support locations and distribution of stiffeners obtained from the hybrid optimization have better mechanics properties than the optimized results of the housing structure with known support locations. Reference | Related Articles | Metrics | Comments（0）

Select

Analysis and Optimization of Meshing Performance of Straight Bevel Gears Machined by Dual Interlocking Circular Cutters Jinzhan SU, Yaoke FENG, Bin LIU, Xinlong CAO, Linlin SUN China Mechanical Engineering    2025, 36 (8): 1683-1690.   DOI: 10.3969/j.issn.1004-132X.2025.08.004 Abstract （179）   HTML （2）    PDF（pc） （1896KB）（82）       Knowledge map    Save A method for milling/grinding straight-toothed bevel gears using high-efficiency double-arc cutting tools was proposed to improve their meshing performance. A double arc tool was used to simulate a crown-producing wheel， and tool trimming coefficients， the average radius of the cutter disk and the cutting edge angle were introduced to establish a straight bevel gear tooth face model that considered tooth profile and tooth direction trimming. According to the conditions of continuous tangency of two meshing gears， a tooth contact analysis model was established， and combined with tooth clearance， normal flexibility matrix and mathematical planning， a wheel tooth bearing contact analysis model was established. Then with the goal of achieving symmetry in geometric transmission errors and minimising fluctuations in load transmission errors， the tool profiling origin positions was adjusted and tool parameters were optimised. The geometric transmission errors and load transmission errors of the gear were compared before and after optimization. The example results show that the position of the tool reshaping origin affects the symmetry of the geometric transmission errors； the larger the tool reshaping coefficient is， the larger the amount of tooth profile reshaping is， the amplitude of the geometric transmission errors and the amplitude of the load bearing transmission errors will increase； with the decrease of the average radius of the knife holder and the increase of the blade angle， the amount of tooth profile reshaping is increased， and then the area of the tooth surface mark will be reduced. After optimization， the amount of bearing transmission error fluctuation is reduced by 56.54% under the working load， which may effectively reduce the vibration excitation of the gear pairs. Table and Figures | Reference | Related Articles | Metrics | Comments（0）

Select

Rotor Unbalance Recognition Based on Multidimensional Complex Feature Fusion and CNN-GRU Jianjian WANG, Yuhe LIAO, Lei YANG, Jiutao XUE China Mechanical Engineering    2025, 36 (9): 1905-1915.   DOI: 10.3969/j.issn.1004-132X.2025.09.001 Abstract （220）   HTML （10）    PDF（pc） （3434KB）（81）       Knowledge map    Save The existing unbalance identification algorithm without trial weight adopted an optimization algorithm framework and approximated the optimal solution through numerous iterative operations. However， such strategies typically faced the limitations of slow convergence speed and the tendency to fall into local extrema. Therefore， neural networks were used to directly learn and analyze the complex mapping relationship between unbalance vibration response and unbalance， thus realizing high-precision unbalance identification. A sufficient unbalance vibration dataset with labels was constructed by simulating the rotor dynamics model. A feature fusion mechanism was designed to address the multi-dimensional complex-valued characteristics of unbalanced data. At the core algorithm level， a CNN-GRU hybrid model was constructed. In this model， CNN was responsible for extracting local spatial features from vibration data， while GRU captured temporal dependencies within the vibration data. By integrating information from both spatial and temporal domains， the model’s generalization ability and recognition accuracy were significantly enhanced. The unbalance recognition results of test set data and experimental bench demonstrate that this method may accurately predict the unbalance of the rotors， providing a rapid and accurate guide for dynamic balancing in the field without trial weights. Table and Figures | Reference | Related Articles | Metrics | Comments（0）

Select

Adaptive Impedance Control of Hexapod Robots Based on Virtual Motoneuron System LIU Chunchao1, ZHU Yaguang1, 2, ZHOU Yating1, HAN Zhigang1 China Mechanical Engineering    2025, 36 (02): 315-324,332.   DOI: 10.3969/j.issn.1004-132X.2025.02.014 Abstract （256）      PDF（pc） （16349KB）（81）       Knowledge map    Save A hexapod robot platform was established by emulating the structural configuration of an animal torso. An online adaptive motion controller was introduced, which achieved impedance control parameter online learning by mimicking the compliant joint motions of the human arm. Integrated with the existing virtual motoneuron system, the hexapod robot dynamically adapted walking gaits and sped online to cope with diverse complex terrains. The adaptive motion controller exhibited versatility in accommodating different tasks and unknown robot dynamics, enhancing trajectory tracking stability. Finally, through simulation models and physical testing of the hexapod robots, the results demonstrate the effectiveness of the proposed approach in enhancing the robots adaptability. Reference | Related Articles | Metrics | Comments（0）

Select

Study on Lubricating Performances and Mechanism of Nano-carbon Balls Cutting Fluids SUN Hao1, LAN Qixin2, YAO Bin2, LU Jingjing1, ZHANG Jinhui2, PAN Zhirong2, ZHAO Kexin2 China Mechanical Engineering    2025, 36 (04): 715-723.   DOI: 10.3969/j.issn.1004-132X.2025.04.008 Abstract （1554）      PDF（pc） （8056KB）（81）       Knowledge map    Save Nano-carbon balls cutting fluid was applied to the cutting processes of difficult-to-machine aerospace gear steels(15Cr14Co12Mo5Ni2W), and the lubrication enhancement effects of nano-carbon particles on the cutting fluid were investigated. Firstly, a cutting force model for metal cutting was established to analyze the relationship between cutting lubrication and cutting forces. Furthermore, through combined friction-wear tests and milling experiments, the lubrication performance of nano-carbon balls cutting fluid was evaluated in terms of friction coefficient, wear volume, friction surface quality, and cutting forces. Compared with the base cutting fluid, when the mass fraction of nano-carbon is reached 0.02%, the milling forces for the gear steels are decreased by over 10%, and surface roughness is reduced by more than 15%. Experimental observations reveal that nano-carbon particles on the friction contact surfaces preferentially are adsorbed onto micro-peak regions with higher surface free energy, forming a nano-carbon adsorption film. Lubrication mechanism analysis indicates that this adsorption film may exert a friction-reducing “micro-bearing” effects. Reference | Related Articles | Metrics | Comments（0）

Select

Mesoscale Numerical Simulation of SLM Processes for Al-Mn-Sc-Zr LI Xinyu1, 2, 3, ZHOU Yonghua1, 2, 3 China Mechanical Engineering    2025, 36 (03): 584-592，603.   DOI: 10.3969/j.issn.1004-132X.2025.03.022 Abstract （179）      PDF（pc） （13297KB）（79）       Knowledge map    Save The microstructure and defects of parts produced by SLM were closely related to the quality of SLM single/double-track forming, and experimental methods were difficult to explain complex physical phenomena of track forming at mesoscale. Al-Mn-Sc-Zr alloy was used as forming material to establish a mesoscale numerical model for SLM single/double-track. SLM single/double-track forming experiments were conducted, and the accuracy of model was verified. Numerical model was employed to reveal the basic laws of SLM molten pool evolution. The variation of molten pool characteristics such as single-track morphology, molten pool temperature, and molten pool size was investigated with laser power ranging in 200~400 W. The best quality of single-track is achieved at a laser power of 360 W and a scanning speed of 1.0 m/s. The overlapping behavior and the evolution law of double-track at scanning speed of 1.0 m/s, the laser power of 360 W and the scanning distance of 60 μm, 80 μm and 120 μm were investigated. Results show good molding quality and high molding efficiency are reached with a scanning distance of 80 μm. Suitable VED is screened in combination with multi-track SLM experiments. In the VED range of 107~139 J/mm3, the multi-track is continuous and smooth. With the help of the model, key processing parameters may be initially predicted, and reduce the cost of processing parameter optimization. Reference | Related Articles | Metrics | Comments（0）

Select

China Mechanical Engineering    2025, 36 (01): 0-.   Abstract （197）      PDF（pc） （360KB）（78）       Knowledge map    Save Related Articles | Metrics | Comments（0）

Select

Experimental Study of Machining Micro Holes in Cf/SiC Composite Materials Using Brazed Diamond Milling Head HONG Mengjie, CHEN Zhuo, ZHOU Jiayi, WANG Haixu, WANG Jianyu, HUANG Guoqin China Mechanical Engineering    2025, 36 (03): 391-397.   DOI: 10.3969/j.issn.1004-132X.2025.03.002 Abstract （291）      PDF（pc） （14837KB）（77）       Knowledge map    Save Cf/SiC ceramic matrix composites were typical high hardness and brittleness ones difficult to machine that combined anisotropy and heterogeneous structures. It was difficult to machine micro holes with a pore size of less than 5 mm, and always was a hot research topic in the industry. Three types of small diameter diamond milling heads was used for hole machining experiments, the preparation method of milling heads and the influences of end geometry on drilling forces, service life, micro hole defects, and tool surface quality were studied. The results show that the micro hole defects produced by the core brazing milling head are the least and the service life is 3.6 times that of the flat bottomed electroplating milling head and 2 times that of the flat bottomed brazing milling head,the core taking brazing milling head has an end face core taking structure, which may reduce drilling force and significantly improve the service life of the tool and the surface quality of the machined workpieces effectively. Reference | Related Articles | Metrics | Comments（0）