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    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
    Abstract310)      PDF (50387KB)(450)       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.
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    Intelligent  Manufacturing——Main Direction  of "Made  in  China 2025"
    Zhou Ji
    China Mechanical Engineering    2015, 26 (17): 2273-2284.  
    Abstract7679)      PDF (1586KB)(24303)       Save

    How to transform from a big nation in manufacturing  to  a  powerful one is a great subject of China's  economic development in the new era.This paper discussed  the guiding ideology,strategic deployment,basic policy and strategic measure of “made in China 2025” based on detailed analyses of current manufacturing situations  of China,and indicated  that “Internet+advanced manufacturing+modern service industry” will become a new engine of China's economic development.It  is pointed  out that digitization,networking and  intellectualization of manufacturing industries  are the core technologies of  a new round industrial revolution, and should be used as commanding point,breakthrough and main direction of  “made in China 2025”.An overall thorough interpretation of above points was put forward.

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    Calculation Method of Time-varying Meshing Stiffness of Small Module Gear Transmissions
    HU Bo, AN Jinyun, YIN Lairong, ZHOU Changjiang
    China Mechanical Engineering    2024, 35 (01): 74-82.   DOI: 10.3969/j.issn.1004-132X.2024.01.007
    Abstract84)      PDF (10849KB)(184)       Save
    Due to the small center distance, the dynamic performance of small modulus gear transmissions was very sensitive to the center distance errors. In addition, the intermediate gears were often designed to rotate at high speed on the fixed shaft, and there were clearances between the gear center hole and the shaft. Therefore, the calculation model of the gear mesh characteristic parameters and time-varying mesh stiffness under the influences of the center distance errors and the shaft hole fit clearances was established, and the influence laws of the two factors mentioned on the mesh stiffness were investigated. The results show that the center distance errors will change the contact degree and meshing stiffness of the gear pairs. The shaft hole clearance causes the actual center distance to fluctuate periodically around the theoretical center distance, which leads to the coexistence of the strengthening and weakening regions of the meshing stiffness in the whole cycle. The influences of center distance errors and shaft hole fit clearances both superimposed and weakened each other in different angle ranges, resulting in the difference in meshing stiffness of each gear tooth, and the risk of inducing greater vibration and different noise.
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    Design of 3K Planetary Gear Reducers with No Backlash
    WANG Weijun, YANG Guilin, DU Qinghao, CHEN Qingying,
    China Mechanical Engineering    2024, 35 (01): 36-44,55.   DOI: 10.3969/j.issn.1004-132X.2024.01.003
    Abstract124)      PDF (10399KB)(170)       Save
    Due to the presence of clearances in the gearing of 3K planetary gear reducers, transmission clearances were introduced into the transmission chain, resulting in a decrease in transmission accuracy and causing impacts during driving direction changes. By utilizing the characteristics that the carrier did not participate in torque transmission in 3K planetary gear transmission, a flexible planetary carrier was innovatively proposed to eliminate clearances of 3K planetary gear reducers, and the effectiveness of the proposed clearance elimination mechanisms was verified through simulation analysis. Gear matching and efficiency optimization were performed to achieve high forward and backward driving efficiency. Through the development of a prototype and testing of transmission accuracy, hysteresis characteristics, sinusoidal response error, transmission efficiency, and reverse starting torque, the effectiveness of the proposed flexible planetary carrier in eliminating clearances, transmission accuracy improvement, transmission efficiency and reverse transmission performance promoting was verified. 
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    Review on Hybrid Flow Shop Scheduling Problems
    LI Yingli;LI Xinyu;GAO Liang
    China Mechanical Engineering    DOI: 10.3969/j.issn.1004-132X.2020.23.004
    Accepted: 18 December 2020

    Brief Analysis of a BigDog Quadruped Robot
    DING Liang-Hong, WANG Run-Xiao, FENG Hua-Shan, LI Jun
    China Mechanical Engineering    2012, 23 (5): 505-514.  
    Abstract2584)      PDF (681KB)(8199)       Save
    Based on the current technical information of a BigDog quadruped robot which was released, the overall profile and the core technology of the BigDog robot were analyzed herein. Structural characteristics, motion characteristics and high power density issues arising from these were analyzed emphatically in the mechanical system. The basic components of the BigDog's hydraulic drive system were analyzed briefly. Biomimetic structure defects restricted the BigDog's maneuverability to further promotion. In rough terrain, the motion control of BigDog firstly depends on the detection of body posture and perception of the terrain. Security posture is the prerequisite for BgDog's continuous longitudinal motion. The basic walking control algorithm was analyzed briefly. The output characteristics of the hydraulic system just meet BigDog's dynamic requirements. Control implementation process was known by analyzing several typical states of motion. Navigation system of BigDog, in particular fully autonomous navigation part is the emphasis. In unstructured environments, the intelligence of mobile robot mainly depends on the design of navigation system. At last, based on author's research experience on quadruped robot, some suggestions of the research and development on the quadruped robot were proposed.
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    An Overview and Recent Research Progresses of Vertical Axis Wind Turbine
    YANG Yi-Fei, BO Wei, SHU Huang-Qiu
    China Mechanical Engineering    2013, 24 (5): 703-709.  
    Abstract1285)      PDF (583KB)(3278)       Save

    This paper formulated several main types of vertical axis wind turbine and their characteristics, operation principles and applications were discussed. The improvement on performance in improving wind power coefficient and the latest development of the main key part were presented. The viewpoints are that vertical axis wind turbine will be the development tendency of wind power. Finally, the conclusion gives a simple view of problems that need further study on the basis of the shortage of the vertical axis wind turbine.

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    China Mechanical Engineering    2024, 35 (01): 0-.  
    Abstract101)      PDF (339KB)(140)       Save
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    On Big Data Driving Manufacturing from “Internet Plus” to “AI Plus”
    YAO Xifan, LEI Yi, GE Dongyuan, YE Jing
    China Mechanical Engineering   
    Accepted: 29 January 2019

    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
    Abstract1758)      PDF (8557KB)(528)       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.
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    Design of Cross-spring Flexure Hinges
    WU Hao, LI Zongxuan, ZHANG Defu, LI Qingya, LI Yunfeng,
    China Mechanical Engineering    2022, 33 (10): 1203-1209.   DOI: 10.3969/j.issn.1004-132X.2022.10.009
    Abstract394)      PDF (4097KB)(321)       Save
    To realize the requirements of a certain optical instrument for flexural hinges, a new type of cross-spring flexural hinge was proposed, and the design method was studied by using the Castiglianos second theorem. First, the Castiglianos second theorem was used to derive the flexibility calculation formula of the cross-spring flexural hinges to determine the axial rigidity and rotational rigidity of the hinges. Then, a case design was carried out and the finite element analysis was used for simulation. Finally, an optical test platform was set up and the rotation stiffness of the example was measured. The results show that the analytical solution, the simulation solution and the experimental data are in good agreement, and the relative error is as 8.7%. Using the Castiglianos second theorem as a design tool, the designer may determine the dimensional parameters according to the rigidity and structural requirements of the cross-spring flexural hinges, and the design of the cross-spring flexural hinges provides a new approach method for other hinges. 
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    Industrial Engineering and Lean Management for Smart Manufacturing
    QI Ershi, HUO Yanfang, LIU Hongwei
    China Mechanical Engineering    2022, 33 (21): 2521-2530.   DOI: 10.3969/j.issn.1004-132X.2022.21.001
    Abstract1516)      PDF (4622KB)(1083)       Save
    This paper reviewed the development routes of developed countries such as the United States, Japan, and Germany since the emergence of industrial engineering for more than 100 years, discussed the regular characteristics of enterprise management innovation, and drew the conclusion that smart manufacturing also needed IE/LM to provide management support. According to the smart manufacturing project cycle, the functions of IE/LM in smart manufacturing engineering were analyzed from the perspectives of basic preparation, scheme selection, and integration development. The framework of lean smart management system for smart manufacturing transformation of Chinese enterprises was given, and the improvement ideas and methods of smart-lean integration were explained based on a case. Finally, some key technologies of smart manufacturing management facing transformation and upgrading of Chinese enterprises were presented based on the actual needs of China. 
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    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
    Abstract233)      PDF (3896KB)(259)       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.
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    Additive Manufacturing—Current Situation and Future
    LU Bingheng,
    China Mechanical Engineering   
    Accepted: 17 January 2020

    Review of Fault Diagnosis and Health Monitoring for Wind Power Equipment
    CHEN Xuefeng, GUO Yanjie, XU Caibin, SHANG Hongbing
    China Mechanical Engineering   
    Accepted: 11 April 2020

    Extraction Approach of Patent Information Based on Regular Expression
    Qiu Qingying, Zheng Guomin, Feng Pei’en, Wu Jianwei
    China Mechanical Engineering    2007, 18 (19): 2326-2329.  
    Abstract1433)      PDF (5273KB)(2418)       Save

    Since current patent documents are saved as image-based type such as .TIF, .PDF, and so on, they are difficult for full-text search and further analysis. The approach that adoped the optical character recognition (OCR) tool and the fault-tolerant regular expressions was proposed for patent digitization and information extraction according to the structural features of patent documents. The software system was developed to support the batch extraction of patent information, which provided the data resources for the following automatic patent analysis and knowledge mining.

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    Review on Research Status of Positioning Accuracy Reliability of Industrial Robots
    WU Jinhui1,2;TAO Yourui1,2
    China Mechanical Engineering    DOI: 10.3969/j.issn.1004-132X.2020.18.005
    Accepted: 07 October 2020

    Effects of Polished Surface Quality on Corrosion Resistance of Stainless Steel Products
    HUANG Jia-1, YAN Qiu-Sheng-1, LU Jia-Bin-1, LIU Bing-Yao-2, CHEN Yong-Jin-2
    China Mechanical Engineering    2012, 23 (21): 2573-2577.  
    Abstract677)      PDF (594KB)(1602)       Save

    The chemical immersion method and potentiodynamic polarization method were employed to investigate the effects of surface roughness on corrosion resistance of 304 stainless steel in neutral chloridion solution. The results indicate that with increase of the surface roughness, the mean maximum depth and size of the pits increase. The surface openness parameter δ is proposed to characterize the smoothness degree of the polished surface, and it is approximate negatively and linearly correlated with the pits depth and size. The surface openness parameter δ is more greater, the breakdown potential Eb is more higher, the maintaining passivity current Jpass is more smaller and the corrosion resistance is much better. 

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    Analysis and Numerical Simulation of Film Thickness of Photoresist Spin Coating
    Liu Xueping, Zheng Gang,
    China Mechanical Engineering    2015, 26 (6): 733-736,742.  
    Abstract560)      PDF (481KB)(1471)       Save

    The spin coating method was an important method for photoresist coating in the photolithography process. Based on the mode of the classical EBP equation and solvent evaporation mode which considered the relationship between the solvent evaporation and spin speed, and the dynamic parameter compensation was added through the numerical simulation of the transition point to get a further modified equation. The validity of the modified equation was verified by the experimental data collected by the lab made spin coating device. More reasonable process parameters can be obtained with this optimized fitting method.

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    Development History and Future Trends of Numerical Control Machine Tools
    LIU Qiang,
    China Mechanical Engineering    2021, 32 (07): 757-770.   DOI: 10.3969/j.issn.1004-132X.2021.07.001
    Abstract2679)      PDF (11426KB)(1870)       Save
     From the viewpoints of industrialization and technology development, the paper summarized the revolutionary history of machine tools and the development processes of NCMT, with the analysis of the kernel technologies of NCMT. The development process of NCMT in China was divided into 3 periods, initial development, consistent technical research and industrialization, and highspeed development, transformation and upgrading as well. The milestone events and achievements were introduced. The industrial scale of NCMT all over the world and the advanced NCMT technologies in several developed countries were presented, followed by the comparative analysis of respects relative with NCMT at home and abroad. Finally, the future development trends were summarized prospectively.
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    Robot Error Compensation Algorithm by Pseudo Target Iterative Generation
    YE Bosheng, JIN Xiongcheng, LI Han, SHAO Baiyan, LI Xiaokun, LI Siao
    China Mechanical Engineering    2024, 35 (01): 136-143.   DOI: 10.3969/j.issn.1004-132X.2024.01.013
    Abstract79)      PDF (2535KB)(101)       Save
    Aiming at the problems of error compensation after robot error modeling, an improved algorithm was proposed based on pseudo target iteration. This algorithm generated a new pseudo target in each iteration to correct the joint angles, thereby continuously reducing the actual errors of the robot. The pseudo target iterative algorithmic process was improved to mature the algorithm flow, 5 new and different false target generation methods were proposed, and the characteristics and applicable scenarios of each method were analyzed. An ensemble algorithm was proposed combining multiple false target generation methods to further improve the accuracy of error compensation. Using the HSR-JR612 robot to carry out simulation experiments, the simulation results show that the algorithm takes milliseconds and the compensation effectiveness is good, and the integrated algorithm may further improve the pose compensation effect. Finally, the UR10 robot and the laser tracker were used for experiments. The experimental results show that after compensation, the position errors of the robot end may be reduced to less than 0.06 mm, and the attitude errors may be reduced to less than 0.025°.
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    Low-speed Dead Zone Adaptive Compensation Method for Drive Units of Supernumerary Robotic Limbs
    CHEN Zhongyuan, CHEN Ke, LIU Hao, OUYANG Xiaoping,
    China Mechanical Engineering    2024, 35 (01): 56-66.   DOI: 10.3969/j.issn.1004-132X.2024.01.005
    Abstract110)      PDF (10271KB)(99)       Save
    To improve the control accuracy of high power density drive units in supernumerary robotic limbs, a low-speed dead zone adaptive compensation method was proposed. Firstly, the drive unit model was established based on the least square system identification and damping identification methods. Then, a computed torque control method for the drive units was proposed. Finally, an adaptive compensation method for the low-speed dead zone of the drive units was proposed and verified. The experimental results show that compared with the traditional PID control method, the maximum angle tracking errors of the drive units are reduced by about 53% and the average angle tracking errors are reduced by about 38% after the computed torque control method is utilized. Based on the computed torque control method, the maximum angle tracking errors of the drive units are reduced by about 45% and the average angle tracking errors are reduced by about 60% after the low-speed dead zone adaptive compensation method is adopted. The control accuracy of the drive units is significantly improved.
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    Finite Element Mesh Generation and Decision Criteria of Mesh Quality
    LI Hai-Feng-1, TUN Ji-Chuan-2, LIU Jian-Bei-1, LIANG Yu-Bing-1
    China Mechanical Engineering    2012, 23 (3): 368-377.  
    Abstract1650)      PDF (684KB)(12286)       Save
    Some general problems in mesh generation were discussed, the demands of mesh generation were expounded, the mesh generation methods were introduced, the mesh generation algorithms in last ten years were retrospected and their advantages and disadvantages were compared. Based on the requirements of practical engineering calculation,the authors brought up the mesh quality demands and decision index, explored the mesh quality optimization, introduced the preprocessors and their applications of the commercial softwares,then gave out several practical examples of the mesh generation. At last, the trends of mesh generation were also presented.
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    Matching Design of Distributed Propulsion Systems for Hydrogen-Lithium Batteries Powered Commuter Aircrafts
    WANG Yu, WU Tingjia, LI Xiang, YU Xiongqing,
    China Mechanical Engineering    2024, 35 (01): 27-35.   DOI: 10.3969/j.issn.1004-132X.2024.01.002
    Abstract108)      PDF (6663KB)(95)       Save
    Aiming at the overall design parameters and mission profile requirements of commuter aircrafts, according to the hydrogen-lithium propulsion system architecture scheme, the propulsion system parameter matching method and energy dynamic balance management strategy were proposed. A 19-seat commuter aircraft was used to select and manage the power plant and reserve energy. According to the selected distributed aerodynamic layout scheme, then the effects of propeller rotation directions on aircraft aerodynamic characteristics were analyzed with full factorial design of experiments, and the optimum propeller rotation direction configuration for aircraft cruise states was obtained.
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    Big Data Driven Intelligent Manufacturing
    ZHANG Jie, WANG Junliang, LYU Youlong, BAO Jinsong
    China Mechanical Engineering   
    Accepted: 29 January 2019

    Review on Scheduling Algorithms for MOFJSP
    Peng Jiangang, Liu Mingzhou, Zhang Mingxin, Zhang Xi
    China Mechanical Engineering    2014, 25 (23): 3244-3254.  
    Abstract923)      PDF (656KB)(1973)       Save

    A mathematical model and related definitions of MOFJSP were introduced and the related theories and the research fruits of MOFJSP were summarized. The emphasis was focused on review both of the computational intelligent algorithms and the intelligent search methods. Some future research directions and contents of optimization scheduling algorithms were pointed out and suggestions of related researches in the future were proposed.

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    Advances in Fluid Dispensing Technology for Micro-electronics Packaging
    SUN Dao-Heng, GAO Dun-Chuan, DU Jiang, JIANG Yi-Wen, DAO,WEI,WANG Ling-Yun
    China Mechanical Engineering    2011, 22 (20): 2513-2519.  
    Abstract1075)      PDF (660KB)(3032)       Save
    Fluid dispensing is a process to dispensing the fluid accurately in a controlled manner,it is one of the key technologies of microelectronics packaging.At present, there is an evolution in the fluid dispensing technology for applying fluids from contact methods to non-contact methods, such evolution will bring a great change for the dispensing industry.Based on the applications of dispensing technology in microelectronics packaging processes,dispensing technical development process was overviewed.Contrasting the features and performances of various methods,the non-contact jetting technology was mainly highlighted,including its key technologies and the evaluation standard of dispensing quality.
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    Present Situation and Development Tendency of Snake-like Robots
    Su Zhong, Zhang Shuangbiao, Li Xingcheng
    China Mechanical Engineering    2015, 26 (3): 414-425.  
    Abstract540)      PDF (861KB)(2878)       Save

    A literature survey of researches on snake-likes was provided regarding morphology, modeling of kinematics and dynamics, locomotion control and stability. The analyses and summary were made according to the two-dimensional and three-dimensional locomotions. Classifications of snake-like robots were presented due to the differences of structures and movement types. Finally, the development of snake-like robots in future was predicted.

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    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
    Abstract669)      PDF (5220KB)(489)       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.
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    The State-of-art and Future Development Strategies of Green Manufacturing
    CAO Huajun, LI Hongcheng, ZENG Dan, GE Weiwei
    China Mechanical Engineering   
    Accepted: 11 April 2020

    Study on Vibration and Fatigue of Distributed Connection Structures of Reusable Aircrafts
    SHEN Minmin, SHI Rui, GUO Pengfei, YANG Yang, YANG Xiaodong, YANG Jihou
    China Mechanical Engineering    2024, 35 (01): 45-55.   DOI: 10.3969/j.issn.1004-132X.2024.01.004
    Abstract94)      PDF (9287KB)(87)       Save
    Accurate calculation of the vibration characteristics and fatigue life of the distributed connection structures between reusable spacecraft and engines was crucial for ensuring the safe operations of aerospace transportation systems. Focusing on the distributed connection structures, the feasibility of experimental validation for finite element simulation methods was demonstrated. The vibration characteristics of the distributed connection structures were explored in both of the time and frequency domains, and the fatigue lives of the structures were calculated under different operating conditions. The findings reveal a commendable concordance between the finite element results of the hysteresis curve for the connection structures and experimental observations. Under cyclic loading at different excitation frequencies, the connection bolts manifest stress increments or decrements, indicative of fatigue effects. The distributed connection structures elicit significantly heightened responses at the 1st and 5th natural frequencies. Decreasing the excitation magnitude substantially augments the fatigue lives of the connection structures, and an escalation in bolt pre-tightening forces is found to enhance fatigue lives as well. However, an increase in excitation frequency only marginally diminishes the operational lifespans, while the cyclic lifespans persist within the same order of magnitude. Furthermore, following the introduction to thermal and creep effects, the distributed connection structures may withstand a maximum of only five thermal cycling loads.
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    Research on Multi-axis Road Simulation Test of a New Type of Commercial Vehicle Cab
    ZHOU Song, CHEN Yu, DONG Hongliang, GAO Xiang, SHEN Juan, ZHOU Jia, WAN Xinming
    China Mechanical Engineering    2023, 34 (10): 1241-1250.   DOI: 10.3969/j.issn.1004-132X.2023.10.014
    Abstract234)      PDF (10957KB)(187)       Save
    In order to improve the control accuracy of commercial vehicle cab multi-axle road simulation test bench and accurately reproduce the collected signals of road spectrum, a control strategy of multi-axle road virtual test bench was proposed based on kinematics and dynamics analysis. According to the principle of mechanisms, the structures of the test benches were described, the kinematics analysis and calculation were carried out. The closed-loop feedback degree of freedom decoupling was carried out by using the inverse pose solution algorithm and the forward solution algorithm with Jacobian matrix. The rigid-flexible coupling multi-body dynamics models of the cabs, part of the frames and the test benches were established by measuring the relevant parameters of the cabs and combining with ADAMS software. The Femfat-lab, MATLAB/Simulink and ADAMS software interfaces were established for adaptive co-simulation calculation to realize the decoupling control of freedom of the test bench. The multi-axis virtual test benches were combined with the internal response signals of the real vehicle tests, and the signals with high signal-to-noise were selected as the target signals for iterative analysis to obtain the equivalent displacement excitation of the real vehicle positions. The typical Belgian road load spectrums were selected as the input condition of the models to reproduce the real road spectrums combined with the road tests. The research results show that compared with the indoor road simulation test benches and the conventional virtual iteration results, the number of iterations of the cabs using the multi axis virtual test benches is significantly reduced, the change trend of the time domain and frequency domain response signals obtained is consistent with the target signal, and the root mean square value of the relative error of each channel is less than the set value, so the iteration accuracy is high. Furthermore, the feasibility of the method was verified, which provided a reliable load spectrum for the subsequent fatigue life prediction of the cabs. 
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    Structural Parameter Design and Accuracy Analysis of Binocular Vision Measuring System
    Liu Qiong;Qin Xiansheng;Yin Shenshun;He Feng
    J4    2008, 19 (22): 0-2649.  
    Abstract1802)      PDF (5034KB)(3755)       Save

    In order to improve the measurement precision for visual measuring system,the influence of binocular vision structure was investigated.A structural parameter model of binocular visual measuring system was investigated with the trigonometric method.Through analyzing the measuring accuracy of the measuring point in binocular visual measure system,the effect of the structural parameters and the error transfer rules on the visual measurement were probed.According to simulation results, optimal value range of structural parameters is supplied while the error is small.Enough theoretical research is offered for optimization design of binocular visual measure system.

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    Research Status and Development Tendency of Wind Turbine Reliability
    LI Yao1;ZHU Caichao1;TAO Youchuan2;SONG Chaosheng1;TAN Jianjun1
    China Mechanical Engineering   
    Accepted: 04 May 2017

    Internal Force Analysis  and Coordination  of  a 5-UPS/PRPU Redundantly Actuated Parallel Mechanism
    Zhou Xin, Xu Yundou, , Yao Jiantao, Zheng Kuijing, Zhao Yongsheng,
    China Mechanical Engineering    2016, 27 (06): 711-717.  
    Abstract269)      PDF (668KB)(879)       Save

    By  combining the overall Jacobin  matrix and pseudo-inverse matrix method, the internal forces of each driving limb of a 5-UPS/PRPU redundantly actuated parallel mechanism were derived,and a novel internal force  coordination method was presented.By using compatibility equation of deformation, the pseudo-inverse of the overall  Jacobian of the mechanism could be obtained.The internal forces  of the 5-UPS/PRPU parallel mechanism were solved as well,which was  verified by finite element method.To investigate the influences of stiffness of the redundant actuator on the internal forces of each driving limb,the 5-UPS/PRPU redundantly actuated parallel machine tool(PMT)  was  used to illustrate the method mentioned above,and a method to coordinate internal forces was proposed.The analyses show that the actuation wrench of the non-redundant limb and the constraint wrench of the redundant limb can be reduced by increasing the stiffness of the redundant actuator to some extent. The method may be used by mechanism designer and programmer to improve the systems precision and reduce the internal forces of the mechanisms.

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    Mold CNC Machining Recommendation Systems Based on Local Features
    WANG Wei;WANG Huachang;CHEN Songwei;LI Jianjun
    China Mechanical Engineering   
    Accepted: 14 May 2019

    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
    Abstract473)      PDF (3924KB)(346)       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.
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    Dynamic Mechanics Behavior and Constitutive Model of TC4-DT Titanium Alloy Materials
    AI Jianguang, JIANG Feng, YAN Lan
    China Mechanical Engineering   
    Accepted: 03 March 2017

    Related Parallel Machine Online Scheduling Method Based on LSTM-PPO Reinforcement Learning
    HE Junjie, ZHANG Jie, ZHANG Peng, WANG Junliang, ZHENG Peng, WANG Ming
    China Mechanical Engineering    2022, 33 (03): 329-338.   DOI: 10.3969/j.issn.1004-132X.2022.03.009
    Abstract737)      PDF (6559KB)(565)       Save
    To solve the related parallel machine online scheduling problems, the total weighted completion time was taken into account, and an online scheduling method was proposed based on LSTM-PPO reinforcement learning. A LSTM-integrated agent was designed to record the historical variations of workshop states and the corresponding scheduling policy adjustment, and then online scheduling decision was made according to the state information. Meanwhile, the workshop state matrix was designed to describe the problem constraints and optimization goals, additional machine waiting was introduced in scheduling action space to expand solution space, and the reward function was designed to decompose the optimization goal into step-by-step rewards to achieve scheduling decision evaluation. Finally, the model updating and global optimization of parameters was achieved by PPO algorithm. Experimental results show that the proposed method has competitive solutions than the existing heuristic rules, and the proposed algorithm is applied to the production scheduling of the actual workshops, which effectively reduces the total weighted completion time.
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