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|

    In last 2 years
    Please wait a minute...
    For Selected: Toggle Thumbnails
    Research Review of Error Compensation Technology for Ultra-precision Machining
    CHEN Qidi, HU Xiaolong, LIN Min, SUN Xiaoxia, ZHANG Tao, ZHOU Zhixiong
    China Mechanical Engineering    2023, 34 (03): 253-268.   DOI: 10.3969/j.issn.1004-132X.2023.03.001
    Abstract2022)      PDF(pc) (8557KB)(982)       Save
     Ultra-precision machining technology was a key technology in high-end manufacturing fields. At present, ultra-precision machining has entered the nano scale. Mastering the key technology of ultra-precision machining error control, ensuring and improving the machining accuracy of CNC machine tools, become a hot research point to improve the machining and manufacturing levels. This paper systematically summarized the research status and development trend of ultra-precision machining error compensation technology, and focused on the geometric errors, force induced errors, thermal induced errors and their compensation methods, which had the greatest impact on ultra-precision machining. Then, a series of problems of ultra-precision machining in geometric error separation, cutting force, thermal induced error measurement and compensation were deeply discussed, and it is further pointed out that the ultra-precision machining error compensation technology should also pay attention to the development direction of high efficiency, high precision, generalization, modularization, intelligence and flexibility.
    Reference | Related Articles | Metrics | Comments0
    Research Progresses of Superhydrophobic Surface Processing Technology and Abrasion Resistance
    HUANG Yun, HUANG Jianchao, XIAO Guijian, LIU Shuai, LIN Ouchuan, LIU Zhenyang
    China Mechanical Engineering    2024, 35 (01): 2-26.   DOI: 10.3969/j.issn.1004-132X.2024.01.001
    Abstract554)      PDF(pc) (50387KB)(669)       Save
    The abrasion resistance of currently prepared superhydrophobic surfaces is generally poor, which limite the applications in various fields. Studied results found that micro-nano structure and low surface energy were the key factors to achieve superhydrophobic properties. Firstly, based on the mechanism of superhydrophobic surface, the superhydrophobic surface texture was summarized, aiming to solve the wear-prone challenge of micro-nano structures by optimizing the surface texture. Secondly, the superhydrophobic surface processing technology was summarized, and measures to reduce surface energy were analyzed in terms of cost and efficiency which might provide ideas for expanding the superhydrophobic surface processing system. Then, the means of analyzing the abrasion resistance of superhydrophobic surfaces were concluded in detail and the methods of improving the abrasion resistance of superhydrophobic surfaces were described. Finally, the future development prospects of abrasion resistant superhydrophobic surfaces was prospected, with a view to promote the large-scale applications of superhydrophobic surfaces in engineering.
    Reference | Related Articles | Metrics | Comments0
    Digital Transformation Mode and Strategy of SMEs in China
    WANG Baicun, ZHU Kailing, XUE Yuan, BAI Jie, ZANG Jiyuan, XIE Haibo, YANG Huayong,
    China Mechanical Engineering    2023, 34 (14): 1756-1763.   DOI: 10.3969/j.issn.1004-132X.2023.14.013
    Abstract930)      PDF(pc) (5220KB)(667)       Save
    Promoting the digital transformation of SMEs was of great significance for Chinas manufacturing industries to improve quality and increase efficiency. SMEs were facing problems in digital transformation, such as high cost, fuzzy path, talent shortage, and lacking analytical framework and reference paradigm for digital transformation. The key factors to achieve digital transformation were clarified by building an analytical framework for SMEs digital transformation herein. Through case studies, 4 basic path models of digital transformation of SMEs were summarized and proposed. Based on the above researches, targeted suggestions were proposed for SMEs digital transformation in China, so as to promote the digital and intelligent development of SMEs.
    Reference | Related Articles | Metrics | Comments0
    Research on Interaction between Pedestrian and Automated Vehicle
    LYU Wei, GUO Fu , LIU Li, ZHANG Zeyu, WANG Tianbo
    China Mechanical Engineering    2023, 34 (05): 515-523.   DOI: 10.3969/j.issn.1004-132X.2023.05.002
    Abstract677)      PDF(pc) (3924KB)(642)       Save
    From the perspective of the pedestrian-vehicle-environment system, the effects of pedestrian safety facility, AVs yielding behavior, approaching direction and eHMI on pedestrian-AV interaction were investigated. Based on a cave automatic virtual environment(CAVE) simulation platform, the Unity 3D software was utilized to design and develop the AVs driving scenario. Thirty-eight volunteers were recruited for the pedestrian-AV interaction experiments. During the experiments, the participants decision time, decision results and subjective experience were recorded and further statistically analyzed with survival analysis. The results indicate that with the presence of an AV in the traffic, pedestrian safety facility, AVs yielding behavior and eHMI may significantly shorten pedestrians decision time, enhance their interactive experience and improve traffic efficiency. However, the influences of pedestrian safety facility on pedestrians crossing decision and behavior exist from the earlier stage of the crossing gap, compared with AVs yielding behavior. Meanwhile, the efficacy and clarity of a light band-based eHMI are somewhat limited for conveying AVs yielding intention.
    Reference | Related Articles | Metrics | Comments0
    Energy Consumption Prediction Method for Industrial Robots
    TUO Junbo, PENG Qiuyuan, ZHANG Xianmin, LI Congbo
    China Mechanical Engineering    2022, 33 (22): 2727-2732,2740.   DOI: 10.3969/j.issn.1004-132X.2022.22.010
    Abstract628)      PDF(pc) (2858KB)(596)       Save
    Aiming at the defects of complex models, cumbersome operation and high cost of traditional energy consumption prediction methods for industrial robots, a meta-action-based energy consumption prediction method for industrial robots was proposed from the perspective of motion trajectory and action mode of end-effector. First, the meta-actions and energy consumption characteristics of static operations and dynamic operations of industrial robots were analyzed in the first place, and the energy consumption function of static meta-action and dynamic meta-action like axial motion and rotation et al, were built. Then, the motions of the target processes were disassembled based on the proposed meta-action library and the energy sonsumption calculation model of each meta-motion was built. Finally, energy consumption of industrial robots at target processes was realized by combining the energy consumption functions and calculation models. By applying the proposed method, the energy consumption prediction may be realized by disassembling operation processes as long as the energy consumption function of each meta-action was established by measuring meta-action power in advance, so the method has broad application prospects.
    Reference | Related Articles | Metrics | Comments0
    Research on Flexible Job-shop Scheduling Problems with Integrated Reinforcement Learning Algorithm
    ZHANG Kai, BI Li, JIAO Xiaogang
    China Mechanical Engineering    2023, 34 (02): 201-207.   DOI: 10.3969/j.issn.1004-132X.2023.02.010
    Abstract695)      PDF(pc) (4473KB)(522)       Save
    The flexible job-shop scheduling problems were transformed into a Markov decision process, and an algorithm D5QN integrated with 5 kinds of deep Q-network (DQN) optimizations was proposed. In the constructing of Markov process, a set of features was extracted to describe the states, and 3 sets of actions were designed by composite rules. The rewards were mapped by direct and indirect methods. The proposed algorithm was compared with the algorithms based on rules, meta-heuristic, and other reinforcement learning, which verifies the proposed algorithm may further decrease the calculating time, and have feasibility and effectiveness. 
    Reference | Related Articles | Metrics | Comments0
    Evolution of Concept of Machine Composition from the 19th Century to Modern Time
    ZHANG Ce, YANG Tingli, LIU Jianqin
    China Mechanical Engineering    2023, 34 (10): 1135-1139.   DOI: 10.3969/j.issn.1004-132X.2023.10.001
    Abstract534)      PDF(pc) (2405KB)(506)       Save
     With increasing of productivity and development of machines, the concept of “machine composition” also evolved. The requirements of modern society for machines were gradually increasing, and complex machines came from the transformation of traditional machines. Understanding the evolution of machines was a necessary process for the transformation of traditional machines. Marx first described the composition of machines in his Das Kapital, which coincided with the start of the Second Industrial Revolution. However, within only a few years, the control system joined a machine, and Marxs “concept of machine composition” began to be broken through. In the second half of the 20th century, in the Third Scientific and Technological Revolution, the concept of mechatronics emerged, and electronic technology, control technology and sensor technology were integrated into mechanical systems. The evolution processes of the concept of machine composition were explained through the history of the development of machines herein. By analyzing the evolution of the concept of machine composition, a more accurate definition of modern mechanical systems was put forword. It may enlighten people, increase their understanding of the machine itself, which has guiding significance for modern mechanical product designers. 
    Reference | Related Articles | Metrics | Comments0
    Patent Data Driven Product Innovation Design Based on SAO
    LIN Wenguang, LIU Xiaodong, XIAO Renbin
    China Mechanical Engineering    2023, 34 (15): 1765-1777.   DOI: 10.3969/j.issn.1004-132X.2023.15.001
    Abstract419)      PDF(pc) (5241KB)(472)       Save
    The patent data-driven product innovation design method was proposed based on SAO using big data mining technology. Firstly, semantic dependency parsing was used to mine the SAO structure and interaction relationships among product components from patent text databases. Subsequently, a complex network knowledge model was constructed for product systems, and the constraint coefficients of components in the complex network were calculated by using structural hole theory to identify the innovative target components. Then, the semantic similarity coefficients of components were calculated using Word2Vec, and the functional similarity coefficients were calculated using SAO similarity algorithm. And the recommendation algorithm and combination matrix were integrated to achieve structural innovation, functional innovation, and functional optimization. Finally, a typical bathroom shower product was taken as an example to demonstrate the method in detail, which fully verifies the effectiveness and progressiveness of the method. 
    Reference | Related Articles | Metrics | Comments0
    Pivot Steering Control of Off-road Vehicles Driven by In-wheel Motors
    FU Xiang, LIU Zexuan, , LIU Daoyuan, LI Dongyuan,
    China Mechanical Engineering    2023, 34 (10): 1251-1259.   DOI: 10.3969/j.issn.1004-132X.2023.10.015
    Abstract374)      PDF(pc) (6293KB)(461)       Save
    In order to solve the problems of large minimum turning radius and inadequate steering maneuverability of Ackermann steering-based off-road vehicles, a road adaptive pivot steering control strategy was developed by taking advantages of the independent control of vehicle torque driven by in-wheel motors. A seven-degree-of-freedom pivot steering dynamics model was constructed to explain the evolution of the longitudinal and transverse coupled motion tire forces during pivot steering, and a quantitative model was established to quantify the pivot steering resistance moment and transverse sway moment with wheel slip rate and road adhesion coefficient. The desired trajectory of transverse sway angular velocity under different adhesion conditions was designed with steering power responsiveness as the optimization objective, and the safety threshold of each wheel slip rate was used as the stability constraint to reduce the steering center offset. The executive layer tracked the transverse angular velocity based on the model prediction algorithm, while the adaptive sliding mode controller was introduced to adjust the wheel slip rate to ensure the stability of the longitudinal and transverse motions. Simulation tests and real vehicle tests show that the developed pivot steering control strategy achieves accurate tracking of the desired pivot steering trajectory under high, medium and low adhesion surfaces, and limits the steering center offset to within 500 mm, which improves the pivot steering flexibility and lateral stability of the off-road vehicles and realizes "fast and stable" pivot steering. 
    Reference | Related Articles | Metrics | Comments0
    Research on Backlash Elimination Method of Dual-motor Precision Transmission Mechanisms
    ZHENG Jieji, CHEN Lingyu, FAN Dapeng, XIE Xin
    China Mechanical Engineering    2022, 33 (22): 2684-2692.   DOI: 10.3969/j.issn.1004-132X.2022.22.005
    Abstract787)      PDF(pc) (6537KB)(457)       Save
    Aiming at the problems of large speed fluctuation and impact caused by the gaps between the two transmission chains of the dual-motor precision transmission mechanisms, the method of eliminating the gaps of the system was studied. First, a mechanism dynamics model including the meshing clearances between the output gear of the planetary reducer and the large ring gear was established. Through the model simulation, the influences of the gap size on the system characteristics were analyzed. Then, a compound anti-backlash method was proposed combining dynamic bias torque based on speed command and cross-coupling synchronous control based on differential negative feedback. An experimental device for dual-motor precision transmission mechanisms was built, and the verification experiments of the anti-backlash method were carried out. The experimental results show that in the case of closed-loop speed, the proposed compound anti-backlash method may ensure the complete elimination of the system gaps, and may improve the system speed tracking accuracy by 73.38%, and the shock amplitude in the start-up phase may be attenuated by 76.35%. The research results lay a certain foundation for the research of the high-precision control method of the double-motor precision transmission mechanisms, and provide a reference scheme for the elimination of the gaps in the gear transmission systems. 
    Reference | Related Articles | Metrics | Comments0
    Human Factor Engineering for Human-Cyber-Physical System Collaboration in Intelligent Manufacturing
    YANG Xiaonan, FANG Haonan, LI Jianguo, XUE Qing
    China Mechanical Engineering    2023, 34 (14): 1710-1722,1740.   DOI: 10.3969/j.issn.1004-132X.2023.14.008
    Abstract649)      PDF(pc) (5740KB)(452)       Save
    The theoretical system of intelligent manufacturing for HCPS confirmed the central position of human in the intelligent manufacturing system. Starting from the demand of human-machine collaboration in the intelligent manufacturing system, the emphases of human factors in HCIM were discussed from three levels such as behavior, intention, and cognition, based on the theory of gulf. Focusing on virtual-real fusion scenarios, multimodal human-machine interaction, cognitive quantification and other methods, the importance of human factor engineering in promoting the integration of human-computer intelligence was expounded. Finally, research direction and development suggestions of human-centered intelligent manufacturing from the implementation of HCPS intelligent manufacturing systems were put forward.
    Reference | Related Articles | Metrics | Comments0
    Tooth Surface Generation and Meshing Characteristics Analysis of Low-angle Face Gear Drives
    ZHOU Ruchuan, WU Wenmin, FENG Manman, GUO Hui, LIN Yanhu
    China Mechanical Engineering    2023, 34 (06): 631-640.   DOI: 10.3969/j.issn.1004-132X.2023.06.001
    Abstract671)      PDF(pc) (6100KB)(451)       Save
     Gear geometry and meshing properties of the low-angle face gear drives were investigated in order to enhance meshing capabilities of the gear drives with small shaft angle in helicopter transmission systems. The applied coordinate systems for generation of the low-angle face gear drive were established and the equation of the tooth surface of the small cone angel face gear was derived based on gear meshing theory. The tooth surface equation of a double-crowned cylindrical involute pinion was deduced by application of a generating worm.  The generated double-crowned pinion was then introduced into the low-angle face gear drive. The TCA was implemented and the influences of misalignments on the contact were researched. Stress analysis was performed for the purpose of evaluating the performance of the proposed face gear drives. And the stresses of the low-angle face gear drive were compared with the conical involute gear and cylindrical involute gear pair. The results show that the application of double-crowned pinion avoids edge contact, providing lower contact and bending stresses compared with the face-gear drive with a longitudinal modification pinion. Under the same conditions, the contact and bending stresses of the tapered face gear are 27% decrease than that of the conical involute gears. 
    Reference | Related Articles | Metrics | Comments0
    Study on Influences of Ni Content, Nitriding Hardening Depth, and Shot Peening on Bending Fatigue Performance of 42CrMo Gears
    WU Zhongrui, CHEN Difa, WU Jizhan, YANG Yudian, LIU Huaiju
    China Mechanical Engineering    2024, 35 (03): 394-404.   DOI: 10.3969/j.issn.1004-132X.2024.03.002
    Abstract206)      PDF(pc) (9652KB)(440)       Save
     Single tooth bending fatigue tests were conducted on 42CrMo gears with different combinations of Ni content, nitriding hardening depth, and shot peening. The effectiveness of different process combinations on improving the bending fatigue limit of gears was investigated, providing process guidance for gear fatigue resistance manufacturing. Additionally, the contribution of surface hardness, nitriding hardening depth, surface residual stress, and Ni content to the bending fatigue limit of gears with different process combinations was analyzed using the random forest algorithm. A multiple regression model considering surface hardness, nitriding hardening depth, surface residual stress, and Ni content was established to predict the bending fatigue limit of gears. Comparing the predicted values with experimental values, the maximum error is controlled within 7.80%, providing a theoretical basis for the rapid and low-cost assessment of gear bending fatigue limit in engineering applications.
    Reference | Related Articles | Metrics | Comments0
    A Bionic Bouncing Robot Design and Made Inspired by Locusts
    WANG Kaidi, CHEN Suifan, TANG Wei, QIN Kecheng, LI Qipeng, YANG Zhan, LIU Yang, ZOU Jun
    China Mechanical Engineering    2023, 34 (24): 2946-2951.   DOI: 10.3969/j.issn.1004-132X.2023.24.006
    Abstract411)      PDF(pc) (3896KB)(440)       Save
     In order to improve the mobility of small robots and increase the diversity of movement gait, a jumping robot imitating locust bouncing was designed based on the body structure and movement mechanism of locusts, and the main body was made by 3D printing. And for reproducing the locusts bouncing mechanism, a torsion spring was installed at the joints of the robot body to simulate the locusts SLP(semilunar energy storage) mechanism. When the robot met an obstacle, the torsion spring released the stored elastic potential energy and generated a ground reaction force, which realized the robots bouncing and thus crossed the obstacle. The robot might imitate the locusts jumping actions, and simulate the locusts flexibility to a certain extent. It was experimentally verified that the robot has good jumping performance, with a jumping distance of up to 100 cm and a jumping height of up to 120 cm which is about 15 times of the own length.
    Reference | Related Articles | Metrics | Comments0
    Fault Diagnosis Method of Rolling Bearings Based on Simulation Data Drive and Domain Adaptation
    DONG Shaojiang, ZHU Peng, ZHU Sunke, LIU Lanhui, XING Bin, HU Xiaolin
    China Mechanical Engineering    2023, 34 (06): 694-702.   DOI: 10.3969/j.issn.1004-132X.2023.06.008
    Abstract655)      PDF(pc) (6394KB)(434)       Save
    To solve the problem that it was difficult to obtain a large number of high-quality rolling bearing fault data in the actual industrial environment, and the generalization performance of the intelligent diagnosis model was poor, a fault diagnosis method was proposed based on simulation data driven and domain adaptation. Firstly, a physical model was established to obtain rich simulation data, which simulated different failure forms of bearings according to bearing parameters and corresponding operating conditions. Secondly, the transfer learning method was used to solve the problem of inconsistent data feature distributions between simulation and actual fault data. The residual channel attention mechanism network was used to extract the transfer fault features of different domains, and the adaptive operation of different domains in the network training processes was carried out through the condition maximum mean discrepancy metric criterion, which taken into account the conditional distribution discrepancies between different domains. Finally, different transfer model tests were carried out on the bearing data sets damaged by man-made damage and accelerated life test. The results show that the method proposed may obtain better recognition accuracy when the target domain contains a small number of labels. 
    Reference | Related Articles | Metrics | Comments0
    A Topology Optimized Design Method for High-performance Structures with Fluid-thermal-mechanics Coupling
    LI Rongqi, YAN Tao, HE Zhicheng, MI Dong, JIANG Chao, ZHENG Jing
    China Mechanical Engineering    2024, 35 (03): 487-497.   DOI: 10.3969/j.issn.1004-132X.2024.03.011
    Abstract359)      PDF(pc) (5000KB)(428)       Save
    The rapid advancement of topology optimization and additive manufacturing technology provided efficient methods for designing and manufacturing high-performance complex equipment. However, current topology optimization techniques for high-performance structures only considered the design of thermal-mechanics coupling or fluid-thermal coupling, and were mostly limited to simple structures. The design under the combined effects of fluid-thermal-mechanics fields was not considered, which restricted the enhancement of structural performance. This paper tackled the challenge of designing high-performance complex structures under multi-physics fields, encompassing fluid-thermal-mechanics interactions. A topology optimization method was proposed to enhance the ability to withstand temperature of intricate structures. Firstly, the governing equations of flow field, temperature field and structural displacement field were introduced to provide a unified description of the fluid-solid materials within the computational domain. Secondly, the topology optimization model was formulated with fluid-thermal-mechanics coupling. The objective function was set to minimize the average temperature, while flow energy dissipation and structural compliance served as constraint functions. Sensitivity analysis of design variables was carried out by using a combination of the variational method and Lagrangian function. Finally, the established topology optimization model was applied to the structural design of a turbine, resulting in a structure suitable for additive manufacturing with excellent heat dissipation performance and well-balanced flow channel distribution.
    Reference | Related Articles | Metrics | Comments0
    Research on Underwater Gliders Path Tracking Based on Reinforcement Learning Algorithm
    SHI Qingqing, ZHANG Runfeng, ZHANG Lianhong, , LAN Shiquan,
    China Mechanical Engineering    2023, 34 (09): 1100-1110.   DOI: 10.3969/j.issn.1004-132X.2023.09.011
    Abstract405)      PDF(pc) (6340KB)(421)       Save
    Aiming at the large deviations between the actual paths and the predetermined ones of underwater gliders affected by ocean current, a neural network ocean current prediction model with long-term and short-term memory and attention mechanism was established based on the traditional long-term and short-term memory network model.The dynamic Q-table of underwater glider motions was generated by depth neural network, and the optimal motion attitude was selected by reinforcement learning algorithm. Considering the influences of ocean current, an underwater glider path tracking algorithm was constructed based on depth reinforcement learning. The results show that the long-term and short-term memory network based on attention mechanism has less mean square errors and root mean square errors in ocean current prediction than that of the traditional integrated moving average autoregressive model and long-term and short-term memory network.Compared with the traditional PID control, the deep reinforcement learning model may reduce the root mean square errors of the underwater glider trajectory by 50.9%, and significantly improve the path tracking accuracy.
    Reference | Related Articles | Metrics | Comments0
    Review on Management at Mechanical Design and Manufacturing Discipline of NSFC in 2022
    YE Xin, ZHU Mingliang, HUANG Zhiquan,
    China Mechanical Engineering    2023, 34 (04): 379-386.   DOI: 10.3969/j.issn.1004-132X.2023.04.001
    Abstract898)      PDF(pc) (2658KB)(420)       Save
    The applications, evaluations and funding of projects at mechanical design and manufacturing discipline (division Ⅱ of engineering science) of the NSFC in 2022, as well as the research progresses and achievements of the executing and finished projects were reviewed. Specific measures of mechanical design and manufacturing discipline were illustrated, such as the reform of scientific fund, talent cultivation and future research. Finally, a short prospect of the work in 2023 was introduced. 
    Reference | Related Articles | Metrics | Comments0
    Research Progresses of Finishing Technology for Inner Channel of Additive Manufacturing Parts
    WANG Lei, WU Yuliang, ZHAO Jiyuan, LU Bingheng,
    China Mechanical Engineering    2023, 34 (07): 757-769.   DOI: 10.3969/j.issn.1004-132X.2023.07.001
    Abstract540)      PDF(pc) (17271KB)(400)       Save
    In the field of aerospace, metal additive manufacturing technology had broad application prospects in the formation of parts with complex inner channels. However, the finishing of additive manufacturing parts with complex inner channels was a bottleneck problem in industrial applications. The principle, technology and development of mechanical polishing, chemical and electrochemical polishing and electrolyte plasma polishing on inner channel were reviewed herein. In addition, the adaptability and exploration direction of mechanical polishing, chemical and electrochemical polishing and electrolyte plasma polishing for the finishing of inner channel of additive manufacturing parts were studied respectively. Finally, the development trend of the key technologies for the finishing of inner channel of additive manufacturing parts was put forward: ①the finishing technology research of the inner channel of the additive parts for functionally graded materials and polymetallic materials; ②the research on compound finishing technology for complex inner channel with complex geometry, bifurcation, gradual capillary structure, topology and so on; ③the research on high-precision detection method for the finishing quality of inner channel and the three-dimensional reconstruction technology of geometric errors.
    Reference | Related Articles | Metrics | Comments0
    Yaw Rate Calculation and Vehicle Stability Control Considering Tire Nonlinearity
    MIN Delei, TONG Ruting, WEI Yintao
    China Mechanical Engineering    2023, 34 (21): 2521-2530.   DOI: 10.3969/j.issn.1004-132X.2023.21.001
    Abstract403)      PDF(pc) (7794KB)(400)       Save
    Based on the nonlinear tire model, an accurate yaw rate calculation method was proposed to calculate the accurate yaw rate and applied to vehicle stability control. Tire nonlinearity was characterized by the brush model. The equivalent stability factor was obtained by perturbation analysis, and the accurate analytical solution of the yaw rate was obtained. The analysis of the existence of analytical solutions indicates that tire nonlinearity may impact vehicle stability. Real vehicle tests and control simulations based on vehicle models show that considering tire nonlinearity may effectively improve the calculation accuracy of the steady-state yaw rate as the target parameter, and improve the effect of vehicle stability control. 
    Reference | Related Articles | Metrics | Comments0
    Multi-objective Robust Optimization Design Method Based on Adaptive Incremental Kriging Model
    TIAN Zongrui, ZHI Pengpeng, YUN Guoli, GUO Xinkai, GUAN Yi
    China Mechanical Engineering    2023, 34 (08): 931-940.   DOI: 10.3969/j.issn.1004-132X.2023.08.007
    Abstract374)      PDF(pc) (9011KB)(392)       Save
    A multi-objective robust optimization design method of adaptive incremental Kriging model was proposed. Firstly, according to the structural characteristics and optimization objectives, the incremental Kriging surrogate model was constructed, and a hybrid sampling strategy was proposed to improve the adaptability of the incremental Kriging surrogate model. Secondly, the Cauchy mutation MOPSO(CMMOPSO) algorithm was proposed. By improving the inertia weight factor, individual learning factor and social learning factor, and introducing the Cauchy mutation strategy, the efficiency and precision of the optimization model were improved. Finally, an optimization model was constructed with the structural parameters as the design variables, the standard deviation of the performance indicators as the objective, and the 3σ variable reduction interval as the constraint. The optimal solutions of multi-objective robust optimization were obtained combining CMMOPSO and grey correlation analysis. Analysis results of the example show that the proposed method may obtain a high-precision structural optimization model with fewer performance function calls, and the optimization results have faster convergence rate and better robustness than that of traditional methods.
    Reference | Related Articles | Metrics | Comments0
    Design and Experimental Study of a Flexible Winding Forming System for Carbon Fiber Reinforced Carbon/Carbon Crucible Preform
    WANG Zheng, DONG Jiuzhi, CHEN Yunjun, JIANG Xiuming,
    China Mechanical Engineering    2023, 34 (10): 1184-1190,1198.   DOI: 10.3969/j.issn.1004-132X.2023.10.007
    Abstract376)      PDF(pc) (5668KB)(386)       Save
    In order to solve the problems of product consistency and low production efficiency caused by manually reinforced carbon/carbon crucible preforms, a flexible winding forming system of carbon fiber reinforced crucible preform was proposed. The line type design process of crucible core die for special rotary body structure with one end plane head and one end ellipsoid head was presented based on the non-geodesic method. Each module and implementation method of computer aided line type design were introduced, and the design line type was simulated. A special winding machine with four degrees of freedom was designed according to the winding characteristics. The control system of four-axis winding machine was designed based on programmable controller and touch screen, and the winding tests were carried out. It is indicated that the winding machine runs stably and the fiber may be wound continuously and stably on the surfaces of the core die, and the system may realize automatic winding of carbon fiber reinforced carbon/carbon crucible preforms. 
    Reference | Related Articles | Metrics | Comments0
    Study on Design of Wheel-leg Deformable Wheel and Vehicle Control
    GENG Xueqing, WU Mengwu, HUA Lin,
    China Mechanical Engineering    2023, 34 (12): 1446-1452.   DOI: 10.3969/j.issn.1004-132X.2023.12.007
    Abstract389)      PDF(pc) (6422KB)(380)       Save
     In view of the demands of vehicle mobility and obstacle-crossing ability in complex terrain and road conditions, a deformable wheel structure was designed with the characteristics of switching between wheeled and legged states under different terrain and road conditions. The design principle of the deformable wheel was introduced and the structural parameters were calculated and optimized, the maximum diameter ratio of the wheel-leg deformable wheel was obtained. A set of simple and effective wheel-leg deformation control system was also designed. And then the vehicle layout design and movement process analysis was carried out. Finally, a prototype vehicle platform was made to verify the mobility and obstacle-crossing ability by physical experiments. The results show that the deformable wheel may be quickly and intelligently switched between wheeled and legged types, which enables the vehicle to run stably on both structured and unstructured roads, resulting in a high mobility and obstacle-crossing ability of the vehicle system.
    Reference | Related Articles | Metrics | Comments0
    Study on Levitation Characteristics of High Temperature Superconducting Pinned Maglev Train
    ZHANG Mingliang, LI Mingyuan, LIU Pengfei, YAN Yangyang, LIU Liru, YANG Xinmeng
    China Mechanical Engineering    2022, 33 (22): 2764-2771.   DOI: 10.3969/j.issn.1004-132X.2022.22.015
    Abstract527)      PDF(pc) (5461KB)(377)       Save
    Facing the magnetic rail relationship of high temperature superconducting levitation train, the suspension force characteristics between dual-peak permanent magnetic orbit and high temperature superconducting block combination were tested at different field cold heights, and it is found that the magnitudes of suspension forces first increase then decrease as the distance increases, and existe the obvious hysteresis characteristics. In order to optimize the parameters of high temperature superconducting block combination and permanent magnetic track pair, the equivalent processing method for high temperature superconducting block was proposed based on image dipole model. The simulation model was established in order to obtain the trapped magnetic fields. The attractive force and repulsive force of the combination of high temperature superconductor block combination were calculated by way of trapped magnetic field and low relative permeability, and the relationship between suspension force and suspension gap at different field cold heights was gained. The results show that the simulated results are in good agreement with experimental ones at position of near different field cold heights, which verifies the equivalent processing method. The aim of paper is to provide a simple and effective method for the suspension force calculation of high temperature superconducting flux pinned magnetic levitation trains.
    Reference | Related Articles | Metrics | Comments0
    Friction Model of Robot Joints Considering Influences of Temperature
    ZHANG Yinan, DING Jianwan
    China Mechanical Engineering    2023, 34 (02): 127-134.   DOI: 10.3969/j.issn.1004-132X.2023.02.001
    Abstract551)      PDF(pc) (3917KB)(376)       Save
     In order to describe the influences of temperature on serial robot joint friction under continuous operations, a joint friction model was proposed considering the influences of temperature. This friction model might describe the effects of joint temperature changes on joint friction without measuring or estimating temperature. Through experiments, the friction torques of the robot joints were measured as the joint operations continuously at different angular velocities, and the data were fitted based on the theoretical model. By comparing the experimental results, the validity of the joint friction model was verified. This model may describe the variation of joint friction torques more accurately under continuous operations. 
    Reference | Related Articles | Metrics | Comments0
    Robot Welding Trajectory Planning and High Frequency Control for Curved Seams
    WU Chaoqun, ZHAO Song, LEI Ting
    China Mechanical Engineering    2023, 34 (14): 1723-1728.   DOI: 10.3969/j.issn.1004-132X.2023.14.009
    Abstract687)      PDF(pc) (6070KB)(370)       Save
    In a robotic real-time seam tracking system, the trajectory planning and control delay affected the tracking accuracy and welding quality. To solve this problem, a piecewise real-time trajectory planning and control method for curved seams was proposed by combining B-spline curve interpolation algorithm and EGM module. Firstly, the trajectory was segmented according to the principle of optimal interpolation time. Secondly, three times non-uniform B-spline was used to interpolate each trajectory to obtain the interpolation points. Finally, the high-frequency controller of the robot was designed. The interpolation points were sent to the robot by EGM module in a cycle of 4 ms to guide the robot movements. The experimental results show that this method may complete the planning of sine curve weld and guide the robot welding in 100 ms, and the tracking errors were controlled within ±0.2 mm, which realizes the rapid trajectory planning and high-frequency control.
    Reference | Related Articles | Metrics | Comments0
    High Rigidity and Lightweight Design of Purlins in Photovoltaic Tracker Bracket
    DONG Xiaohu, WANG Shitao, ZHOU Dechun
    China Mechanical Engineering    2023, 34 (10): 1207-1213.   DOI: 10.3969/j.issn.1004-132X.2023.10.010
    Abstract468)      PDF(pc) (5559KB)(368)       Save
    In the intelligent photovoltaic tracker brackets, cold-formed purlins were used to support the photovoltaic panels, and located spannig the horizontal single-axis and the module frame. Firstly, the minimum compliance of the structures was taken as the target and relative densities of elements were taken as the design variables, and the topology optimum design models were constructed under the given volume and the first natural frequency constraints. Optimal material distributions of the purlins were obtained based on SIMP (solid isotropic material with penalization) method, and this topology optimization structure was engineering designed and manufactured. Then, test load conditions were designed according to the practical environment where the photovoltaic tracker brackets were applied under different wind loads. The static and dynamic finite element analyses of the original and optimized purlins were carried out respectively, the simulation results show that the optimized purlins are improved in terms of bending resistance, torsion resistance, and natural frequency. Thus, the effectiveness of the optimization design method is verified. After that, the optimal purlins whose mass is reduced by 8.8% were also manufactured by engineering methods, and the mechanics performances were verified by the experiments. 
    Reference | Related Articles | Metrics | Comments0
    China Mechanical Engineering    2023, 34 (14): 1-.  
    Abstract242)      PDF(pc) (69666KB)(365)       Save
    Related Articles | Metrics | Comments0
    Cross-domain Fault Diagnosis of Bearings Based on Discriminant Feature Extraction and Dual-domain Alignment
    DONG Shaojiang, ZHOU Cunfang, CHEN Lili, XU Xiangyang
    China Mechanical Engineering    2023, 34 (15): 1856-1863.   DOI: 10.3969/j.issn.1004-132X.2023.15.010
    Abstract302)      PDF(pc) (4455KB)(363)       Save
     A deep transfer learning method was proposed to address the challenge of inconsistent feature distributions and difficulties in removing noise components in vibration data collected under different operating conditions for rolling bearings. The method utilized a combination of discriminative feature extraction and dual-domain alignment. Firstly, the labeled vibration signals and unlabeled vibration signals were segmented into fixed-length data sets using a data segmentation method. To mitigate the interference of noise signals in practical operating conditions, a channel attention mechanism known as SENet was employed. Additionally, a discriminative loss term was incorporated to assist the feature extractor in extracting features that exhibit discriminative properties. To handle the issue of inconsistent data feature distributions, the MMD was utilized to align the global domain distributions between the source and target domains. Furthermore, conditional adversarial learning techniques were employed to align the sub-domain distributions, resulting in dual-domain alignment. Experimental validation was conducted on two publicly available rolling bearing fault datasets collected under different operating conditions. The results show that the proposed method achieves an average recognition accuracy of over 98%. Comparative analyses with different diagnostic methods further demonstrate the effectiveness and superiority of the proposed method. 
    Reference | Related Articles | Metrics | Comments0
    Design of Multi-link Independent Suspension Systems with Constant Wheel Track
    LI Ronghua, YANG Jingshan, ZHENG Yufeng, ZHOU Wei
    China Mechanical Engineering    2023, 34 (02): 148-156.   DOI: 10.3969/j.issn.1004-132X.2023.02.004
    Abstract536)      PDF(pc) (4532KB)(363)       Save
    In order to solve the existed problems of difficulty in motion control for robots such as track width changes and variety range of camber increases when wheeled mobile robots equipped with conventional suspension surmounted obstacles, a novel independent linkage which was made up of parallel crank mechanisms, offset slider crank mechanisms, and oscillating guide bar mechanisms was designed. Dynamics simulations and analyses were carried out in different terrains with the software ADAMS, and the optimal length of each link was determined. Experiments of robot verified the improvement of controllability, landing ability of the wheels, and the accuracy of robot motions on obstacle surmounting. 
    Reference | Related Articles | Metrics | Comments0
    An Actuating Response Model of Temperature-controlled SMA Actuators
    LU Youjun, SONG Di, MIAO Changqing
    China Mechanical Engineering    2023, 34 (02): 157-163.   DOI: 10.3969/j.issn.1004-132X.2023.02.005
    Abstract530)      PDF(pc) (3937KB)(358)       Save
    Based on heat transfer theory and actuating geometric relationship, an execution response model of temperature controlled SMA actuator was proposed. The parameter values affected by temperature in the model were dynamically modified to improve the response accuracy of the driving model. When the side number of the regular polygon section of SMA wire was less than 8, the laws of improving the response speed were analyzed and obtained. Based on the results of theoretical analysis, the actuating response of SMA wire with a diameter of 1.2 mm, a length of 10π mm, an initial central angle of 30° was tested under a current intensity of 6A. By comparing the experimental results with the theoretical model calculation results, the max error of the whole actuating processes(actuating end point)reduces to 1.8 s, and the execution response model may accurately describe the actuating response. 
    Reference | Related Articles | Metrics | Comments0
    Assessment Method of Environmental Impact of Casting Processes Based on Digital Twin
    GU Zhenyu, HE Yi, LI Dongyang
    China Mechanical Engineering    2023, 34 (12): 1465-1475.   DOI: 10.3969/j.issn.1004-132X.2023.12.009
    Abstract361)      PDF(pc) (4109KB)(346)       Save
    Focusing on the new needs of foundry enterprises to carry out process environmental impacts and carbon emission evaluations, and addressing the issues of consistent management of dynamic data in dynamic evaluations of processes, the casting processes were taken as the research object and the digital twin technologies were introduced into the assessments of the environmental impacts and carbon emissions of the casting processes. A digital twin model of the casting processes for environmental impact assessments was constructed and integrated into the basic process of LCA evaluation, and a digital twin-based method for environmental impact assessments of the casting processes was proposed. By evolving from twin models to instance models and instance twins, the consistency of the process data structure was ensured, while the dynamic scene data carrying was realized by generating instance twins of different stages, and the management of dynamic process data was realized. Finally, the application of the proposed method in the environmental impact assessments of the processes was illustrated by the example of the 3.5-ton carrier V-normal casting processes in a foundry.
    Reference | Related Articles | Metrics | Comments0
    Multi Tooth Meshing Characteristics and Load Bearing Contact Analysis Method of Cycloidal-pin Wheels
    WANG Yongqiang, WEI Bingyang, XU Jiake, YANG Jianjun
    China Mechanical Engineering    2023, 34 (10): 1151-1158.   DOI: 10.3969/j.issn.1004-132X.2023.10.003
    Abstract418)      PDF(pc) (4467KB)(343)       Save
     The tooth profile equations of cycloidal gear were derived by the envelope methods, and the tooth surface contact parameters were obtained. An accurate algorithm for the geometry analysis of the backlash was proposed, which solved the defects that the traditional backlash algorithm might only be used for the constant displacement modification. The tooth by tooth clearance elimination methods were used to solve the deformation compatibility equation, which avoided the error and uncertainty of conventional meshing analysis and improved the calculation accuracy and efficiency of load-bearing contact analysis. The complete calculation flow from tooth surface contact analysis to load contact analysis was given, and the accurate load parameters of any angle position and different modification methods were obtained. 
    Reference | Related Articles | Metrics | Comments0
    Study on Force Model and Surface Integrity of Cylindrical Grinding 18CrNiMo7-6 Steels
    WANG Dong, CHEN Lei, ZHANG Zhipeng
    China Mechanical Engineering    2024, 35 (03): 381-393.   DOI: 10.3969/j.issn.1004-132X.2024.03.001
    Abstract216)      PDF(pc) (8185KB)(339)       Save
     In order to accurately and effectively control the influences of grinding parameters on grinding force and surface integrity, a three-stage grinding force theoretical model was established based on the plastic deformation, indentation theory and shear strain effect between abrasive particles and materials by analytical method. The brown corundum grinding wheels were selected for grinding experiments to explore the effects of grinding parameters on grinding force and the effects of grinding parameters and grinding force on surface integrity. The optimal processing parameters for cylindrical grinding were obtained through orthogonal experiments of cylindrical transverse grinding. The results show that the average prediction errors of normal and tangential grinding forces in the cylindrical grinding force model are 5.56% and 7.08%, respectively. The radial feed speed of the grinding wheel has the greatest impact on grinding force, followed by grinding width, and the influences of workpiece speed and grinding wheel particle size are relatively small. The radial feed speed and grinding width of the grinding wheel have a significant impact on residual stress, and the particle size of the grinding wheel has the greatest impact on surface roughness. As the grinding force increases, the surface roughness value continuously increases, and the residual stress firstly decreases and then increases. The maximum residual stress value along the depth direction firstly increases and then decreases. Within the parameters taken in the experiments, the distribution range of residual stress is basically 20~40 μm. The optimal combination of processing parameters is a radial feed speed of 0.15 mm/min for the grinding wheel, a workpiece speed of 120 r/min, a grinding width of 10 mm, and a grinding wheel particle size of 80.
    Reference | Related Articles | Metrics | Comments0
    Design and Analysis of a Novel Weak-coupling Parallel Hip Exoskeleton with Large Angle of Rotation
    XU Jilong, LIU Fucai, NIU Yunzhan
    China Mechanical Engineering    2023, 34 (21): 2540-2547.   DOI: 10.3969/j.issn.1004-132X.2023.21.003
    Abstract266)      PDF(pc) (7047KB)(335)       Save
    A novel bio-syncretic hip exoskeleton with large-angle and weak-coupling characteristics was proposed to solve the problems such as small workspace, difficult forward kinematics modeling, and complex control of parallel hip exoskeletons. The detailed structures of two-stage prismatic joint were designed, and the expression for calculating the slope of the groove was obtained. The man-machine complexs forward and inverse position solutions were derived by closing-vector-circle method. The inverse Jacobian matrix was obtained by taking the derivative of the inverse position solution equation. Performance analysis shows that the man-machine complex has the advantages such as large range motion, no internal singularities, good force transfer performance, and easy control.
    Reference | Related Articles | Metrics | Comments0
    Isotropy Design and Vibration Reduction of a Three-dimensional Dynamics Vibration Absorber Based on Parallel Mechanisms
    DONG Chenglin, CAI Longqi, LI Yi, LU Tong, ZHANG Luke
    China Mechanical Engineering    2023, 34 (03): 307-313.   DOI: 10.3969/j.issn.1004-132X.2023.03.007
    Abstract399)      PDF(pc) (4922KB)(331)       Save
    Aiming at the multi-dimensional line-spectra coupling vibration control of power machines, a novel three-dimensional DVA was presented based on parallel mechanisms. The novel DVA has the merits of good modularity and small additional mass. On the basis of the establishment of dynamics model in terms of a set of joint coordinates, the modal analytical solution for modal analysis of the DVA was derived, leading to the condition to achieve dynamics isotropic design, and thereby a three-dimensional DVA reducing the line spectra vibration at 50 Hz was obtained. In addition, the effectiveness and advantages of the novel DVA in the applications on line-spectra vibration suppression of power machines were investigated. The results show that the maximum attenuations of the line spectrum response at around 50 Hz along three mutual vertical directions are all above 7 dB after the installation of the three-dimensional DVA, while only the line spectrum response along the direction of freedom may be suppressed effectively after the installation of the unidirectional DVA.
    Reference | Related Articles | Metrics | Comments0
    Design of Hobbing Motion Chamfering Tools for Cylindrical Gears
    HE Kun, HE Xiaohu, DU Yanbin
    China Mechanical Engineering    2022, 33 (22): 2704-2710.   DOI: 10.3969/j.issn.1004-132X.2022.22.007
    Abstract593)      PDF(pc) (6802KB)(331)       Save
    Aiming at the high-speed tooth profile chamfering requirements of cylindrical gears in actual productions, a new method of continuous cutting hobbing motion chamfering was proposed, and the profile design of the hobbing motion chamfering tools was completed. First, referring to the hobbing motion of cylindrical gears, the initial position relationship between the tool and the gear and the tool installation pose coordinate system were established, and the tool installation pose parameters were calculated through the chamfering parameters and the established installation pose coordinate system. Secondly, according to the chamfering motion and tool installation pose, a spatial motion coordinate system and derive the transformation relationship between the coordinate systems, and a tool profile calculation method was established by continuously solving the contact point between the tool rake face and the gear chamfering target profiles. Finally, a certain type of cylindrical helical gear was selected as the chamfering object. The three-dimensional modeling of the gears and the hobbing motion chamfering tools was completed by the cutting simulation software, and the chamfering cutting simulation was realized by writing the simulation motion program, the processing experiments were performed by chamfering machine. The simulation and experimental results show that the designed chamfering tool may meet the requirements of efficient tooth profile chamfering of cylindrical gears, and the correctness of the tool profile calculation method is also verifies.
    Reference | Related Articles | Metrics | Comments0
    Investigation and Application on Overall Design Method of Complex Electromechanical Systems
    YANG Shixiang, LI Wenqiang, SHAO Zhehui,
    China Mechanical Engineering    2023, 34 (01): 47-54.   DOI: 10.3969/j.issn.1004-132X.2023.01.006
    Abstract510)      PDF(pc) (5184KB)(326)       Save
    Complex electromechanical systems embodied the features of diverse design needs, complex structures and redundant information. To improve the quality and efficiency of overall design, a systematic method combined with QFD, AD and Petri net was put forward for overall design of complex electromechanical systems. Based on the transformation relationships of the design information from customer requirements to functional design, physical structures, and processing scenarios, innovative design methods were integrated effectively, which guided the establishment of a standardized design processes including requirement analysis, function-structure mapping, and process layout for complex electromechanical systems. Effectiveness and practicability of the method herein were verified by the overall design processes of an intelligent dusting and bagging system.
    Reference | Related Articles | Metrics | Comments0
    Rotating Eddy Current Testing for Inspection of Cracks at Hole Edge
    ZHU Yulong, ZHAO Yingsong, FANG Yang, CHEN Hongen, CHEN Zhenmao,
    China Mechanical Engineering    2023, 34 (08): 883-891.   DOI: 10.3969/j.issn.1004-132X.2023.08.001
    Abstract429)      PDF(pc) (6432KB)(325)       Save
     Rotating eddy current testing method was applied for reliable ECT of cracks at the cooling hole edge of gas turbine blades. At first, a numerical simulation scheme and code were developed, and numerical results show that the method might find cracks by amplitude modulated rotating ECT. A rotation ECT probe and a inspecting system were designed to inspect test-pieces with cooling holes and cracks at their edges. The consistency of experimental ones and simulation results show that the proposed numerical simulation scheme and rotating ECT are effective for detecting the hole edge cracks. 
    Reference | Related Articles | Metrics | Comments0
    Study on Modeling of Material Removal Depth for Blisk Polishing by ABFW Based on Hertz Contact Theory
    ZHANG Junfeng, WU Xiaojun, SHI Yaoyao, LIN Xiaojun
    China Mechanical Engineering    2023, 34 (06): 668-676.   DOI: 10.3969/j.issn.1004-132X.2023.06.005
    Abstract430)      PDF(pc) (5074KB)(323)       Save
    To investigate the material removal mechanism in complex curved surface polishing with ABFW, it was assumed that the distribution of abrasive grain protrusion heights was normal distribution. The distribution model of polishing pressure between ABFW and blade was obtained based on Hertz contact theory. The force analysis of a single abrasive grain was carried out based on the elastic-plastic contact theory, and then the cutting depth model of the abrasive grain was established combined the height distribution function. Thus, the material removal volume of single abrasive grain was determined by synthesizing the spindle speed, feed speed and the shape of abrasive grain cutting groove, and the material removal depth model was established by integrating along the polishing trajectory. The experimental results show that the maximum deviation and average deviation between the predicted values and the experimental ones of material removal depth are 4.85% and 2.95%, respectively, which verifies the correctness and effectiveness of the established model. 
    Reference | Related Articles | Metrics | Comments0