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学者姓名:赵万华

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A novel precision evaluation and analysis method for the direct driven high-speed feed system EI
期刊论文 | 2019 , 121 , 689-710 | Mechanical Systems and Signal Processing
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Abstract :

The direct driven feed system incorporates the merits of simple structure, high velocity and high acceleration, which has a bright future in the high-speed machine tools. However, because of the absence of the intermediate transmission components, there are different kinds of the disturbances which directly act on the mechanical system, leading to multiform motion errors. The complex motion errors in different motion processes will affect the final dynamic performance of the feed system with different forms and degrees, and finally affect the machining precision of the workpiece. It is of great significance to find a comprehensive and systematic precision evaluation method for the analysis and improvement of the dynamic precision of the feed system. In this paper, based on the motion characteristics and error sources, a novel precision evaluation and analysis method and indexes are proposed for the direct driven feed system. The electromechanical integrated model is established and then the dynamic precision in different motion processes with multi-source inputs are analytical presented. What is more, the experimental verification is carried out with different velocities. The results demonstrate that the proposed method can systematically evaluate the dynamic performance of direct drive high-speed feed system. Finally, the sensitive parameters of the precision evaluation indexes are discussed using the sensitivity analysis method (SAM), and the corresponding improvement measures are put forward. © 2018 Elsevier Ltd

Keyword :

Analytical presentation Dynamic precision Electromechanical integrated Experimental verification Feed systems High-speed machine tools Parameter sensitivity analysis Transmission components

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GB/T 7714 Yang, Xiaojun , Liu, Hui , Yang, Qingyu et al. A novel precision evaluation and analysis method for the direct driven high-speed feed system [J]. | Mechanical Systems and Signal Processing , 2019 , 121 : 689-710 .
MLA Yang, Xiaojun et al. "A novel precision evaluation and analysis method for the direct driven high-speed feed system" . | Mechanical Systems and Signal Processing 121 (2019) : 689-710 .
APA Yang, Xiaojun , Liu, Hui , Yang, Qingyu , Zhao, Wanhua . A novel precision evaluation and analysis method for the direct driven high-speed feed system . | Mechanical Systems and Signal Processing , 2019 , 121 , 689-710 .
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A parametric modeling method for the pose-dependent dynamics of bi-rotary milling head EI SCIE Scopus
期刊论文 | 2018 , 232 (5) , 797-815 | PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART B-JOURNAL OF ENGINEERING MANUFACTURE
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Abstract :

Bi-rotary milling head is one of the core components of five-axis machining center, and its dynamic characteristics directly affect the machining stability and accuracy. During the sculptured surface machining, the bi-rotary milling head exhibits varying dynamics in various machining postures. To facilitate rapid evaluation of the dynamic behavior of the bi-rotary milling head within the whole workspace, this article presents a method for parametrically establishing dynamic equation at different postures. The rotating and swing shafts are treated as rigid bodies. The varying stiffness of the flexible joints (such as bearings and hirth coupling) affected by gravity and cutting force at different swing angles is analyzed and then a multi-rigid-body dynamic model of the bi-rotary milling head considering the pose-varying joint stiffness is established. The Lagrangian method is employed to deduce the parametric dynamic equation with posture parameters. The static stiffness, natural frequencies and frequency response functions at different postures are simulated using the parametric equation and verified by the impact testing experiments. The theoretical and experimental results show that the dynamics of the bi-rotary milling head vary with the machining postures, and the proposed method can be used for efficient and accurate evaluation of the pose-dependent dynamics at the design stage.

Keyword :

parametric modeling method joint stiffness dynamic model pose-dependent dynamics Bi-rotary milling head

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GB/T 7714 Du, Chao , Zhang, Jun , Lu, Dun et al. A parametric modeling method for the pose-dependent dynamics of bi-rotary milling head [J]. | PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART B-JOURNAL OF ENGINEERING MANUFACTURE , 2018 , 232 (5) : 797-815 .
MLA Du, Chao et al. "A parametric modeling method for the pose-dependent dynamics of bi-rotary milling head" . | PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART B-JOURNAL OF ENGINEERING MANUFACTURE 232 . 5 (2018) : 797-815 .
APA Du, Chao , Zhang, Jun , Lu, Dun , Zhang, Huijie , Zhao, Wanhua . A parametric modeling method for the pose-dependent dynamics of bi-rotary milling head . | PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART B-JOURNAL OF ENGINEERING MANUFACTURE , 2018 , 232 (5) , 797-815 .
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An investigation of spectral characteristic of displacement fluctuation and its effect on surface quality in precision machining EI SCIE Scopus
期刊论文 | 2018 , 98 (5-8) , 1605-1615 | INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
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Abstract :

In precision machining, the machining conditions play an important role in part surface quality, because the characteristic of the exciting source in machine tools has a close relationship with the machining conditions. Therefore, this paper investigates the spectral characteristic of displacement fluctuation and its effect on the part surface quality for ball screw feed systems. The spectral characteristic is deduced by an equivalent disturbance model that considers the error sources of permanent magnet synchronous motor drives. In the spectrum of displacement fluctuation, the amplitudes of some spectral components increase with the load force; the corresponding frequencies are even multiples of the fundamental frequency of phase current and of the fundamental frequency of phase current plus or minus the rotor frequency. The resonance due to the variation of spectrum seriously deteriorates the part surface quality, leading to visible and characteristic patterns on the surface of machined parts. In the paper, two solutions to improve the surface quality are proposed and validated, i.e., the control method based on an adaptive filter and the method with constraint of feed rate.

Keyword :

Spectral characteristic Part surface quality Ball screw feed systems Precision machining Displacement fluctuation

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GB/T 7714 Liang, Tao , Zhang, Xing , Zhao, Wanhua . An investigation of spectral characteristic of displacement fluctuation and its effect on surface quality in precision machining [J]. | INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY , 2018 , 98 (5-8) : 1605-1615 .
MLA Liang, Tao et al. "An investigation of spectral characteristic of displacement fluctuation and its effect on surface quality in precision machining" . | INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 98 . 5-8 (2018) : 1605-1615 .
APA Liang, Tao , Zhang, Xing , Zhao, Wanhua . An investigation of spectral characteristic of displacement fluctuation and its effect on surface quality in precision machining . | INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY , 2018 , 98 (5-8) , 1605-1615 .
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Interfacial effects on the dynamic stresses in high speed cutting of heterogeneous materials EI
会议论文 | 2018 , 77 , 151-154 | 8th CIRP Conference on High Performance Cutting, HPC 2018
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Abstract :

The microstructure of materials has an important effect on the chip formation and fracture process during metal cutting. Its heterogeneity makes the dynamic mechanical response of materials complicated, which would become more notable with the increase of cutting speed. In this paper, a spring-network discrete element model was established to characterize the heterogeneous material for cutting simulation. The dynamic stress propagation was investigated during the cutting tool impacting on the workpiece at high speeds. Voronoi tessellation method was utilized to create polycrystalline structures in the model and the stress distribution was discussed. Compared with the results by the homogeneous model, the distribution of dynamic stress in polycrystalline model is obviously discontinuous. Furthermore, the normal stress and shear stress propagates in the workpiece as longitudinal and transverse stress waves, which are reflected and transmitted at interfaces. The fluctuation of stress triaxiality is more obvious and changes significantly with the increase of cutting speed, which provides an idea for explaining the fracture mode transition of material in high speed cutting process. © 2018 The Authors. Published by Elsevier Ltd.

Keyword :

Discrete element modeling Dynamic mechanical response Fracture mode transitions Heterogeneous materials High speed cutting Polycrystalline models Polycrystalline structure Stress wave propagation

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GB/T 7714 He, Yong , Zhang, Jun , Jiang, Yifei et al. Interfacial effects on the dynamic stresses in high speed cutting of heterogeneous materials [C] . 2018 : 151-154 .
MLA He, Yong et al. "Interfacial effects on the dynamic stresses in high speed cutting of heterogeneous materials" . (2018) : 151-154 .
APA He, Yong , Zhang, Jun , Jiang, Yifei , Liu, Zhechao , Qi, Yutong , Zhao, Wanhua . Interfacial effects on the dynamic stresses in high speed cutting of heterogeneous materials . (2018) : 151-154 .
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Effect of the screw-nut joint stiffness on the position-dependent dynamics of a vertical ball screw feed system without counterweight EI SCIE Scopus
期刊论文 | 2018 , 232 (15) , 2599-2609 | PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE
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Abstract :

The study on the position-dependent dynamic characteristics of a vertical ball screw feed system without counterweight is an important step in the enhancement of the structural performance of mini-type vertical milling machines. The ball screw is generally driven by a servomotor, which converts a rotary motion into a linear motion through a screw-nut pair. To assess the position-dependent dynamic characteristics of a vertical ball screw feed system subjected to the influence of the screw-nut joint stiffness, a variable-coefficient lumped parameter model of the system is developed. This model is established taking into account the screw-nut joint stiffness under three different strategies: (1) considering the preload and the weight of the spindle system, (2) considering the elastic deformation but ignoring the effect of the weight, and (3) a perfectly rigid model. The differences between the three models in predicting the position-dependent dynamic characteristics of the system are compared, revealing that the stiffness of screw-nut joint greatly affects the vibratory behavior of the spindle system in the transmission direction. A set of conducted experimental results demonstrate that the stiffness model under the preload and the weight of the spindle system is the most accurate model for the prediction of the position-dependent natural frequency and displacement response of the system with the spindle system position. Therefore, it is more suitable for structure design, performance simulation, and evaluation of a vertical ball screw feed system without counterweight.

Keyword :

Screw-nut joint stiffness position-dependent dynamics spindle system variable-coefficient vertical feed system without counterweight

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GB/T 7714 Zou, Cunfan , Zhang, Huijie , Lu, Dun et al. Effect of the screw-nut joint stiffness on the position-dependent dynamics of a vertical ball screw feed system without counterweight [J]. | PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE , 2018 , 232 (15) : 2599-2609 .
MLA Zou, Cunfan et al. "Effect of the screw-nut joint stiffness on the position-dependent dynamics of a vertical ball screw feed system without counterweight" . | PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE 232 . 15 (2018) : 2599-2609 .
APA Zou, Cunfan , Zhang, Huijie , Lu, Dun , Zhang, Jun , Zhao, Wanhua . Effect of the screw-nut joint stiffness on the position-dependent dynamics of a vertical ball screw feed system without counterweight . | PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE , 2018 , 232 (15) , 2599-2609 .
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Integrated modeling and analysis of ball screw feed system and milling process with consideration of multi-excitation effect EI SCIE Scopus
期刊论文 | 2018 , 98 , 484-505 | MECHANICAL SYSTEMS AND SIGNAL PROCESSING
WoS CC Cited Count: 2
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Abstract :

The present researches about feed drive system and milling process are almost independent with each other, and ignore the interaction between the two parts, especially the influence of nonideal motion of feed drive system on milling process. An integrated modeling method of ball screw feed system and milling process with multi-excitation effect is proposed in this paper. In the integrated model, firstly an analytical model of motor harmonic torque with consideration of asymmetrical drive circuit and asymmetrical permanent magnet is given. Then, the numerical simulation procedure of cutter/workpiece engagement during milling process with displacement fluctuation induced by harmonic torque is put forward, which is followed by the solving flow for the proposed integrated model. Based on the integrated model, a new kind of quality defect shown as contour low frequency oscillation on machined surface is studied by experiments and simulations. The results demonstrate that the forming mechanism of the contour oscillation can be ascribed to the multi-excitation effect with motor harmonic torque and milling force. Moreover, the influence of different milling conditions on the contour oscillation characteristics, particularly on surface roughness, are further discussed. The results indicate that it is necessary to explain the cause of the new kind of quality defect with a view of system integration. (C) 2017 Elsevier Ltd. All rights reserved.

Keyword :

Ball screw feed system Milling process Roughness Integrated modeling Multi-excitation effect Low frequency oscillation

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GB/T 7714 Zhang, Xing , Zhang, Jun , Zhang, Wei et al. Integrated modeling and analysis of ball screw feed system and milling process with consideration of multi-excitation effect [J]. | MECHANICAL SYSTEMS AND SIGNAL PROCESSING , 2018 , 98 : 484-505 .
MLA Zhang, Xing et al. "Integrated modeling and analysis of ball screw feed system and milling process with consideration of multi-excitation effect" . | MECHANICAL SYSTEMS AND SIGNAL PROCESSING 98 (2018) : 484-505 .
APA Zhang, Xing , Zhang, Jun , Zhang, Wei , Liang, Tao , Liu, Hui , Zhao, Wanhua . Integrated modeling and analysis of ball screw feed system and milling process with consideration of multi-excitation effect . | MECHANICAL SYSTEMS AND SIGNAL PROCESSING , 2018 , 98 , 484-505 .
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Thermal error modeling of spindle based on the principal component analysis considering temperature-changing process EI Scopus SCIE
期刊论文 | 2018 , 99 (5-8) , 1341-1349 | International Journal of Advanced Manufacturing Technology
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Thermal error is one of the most significant factors that influence the machining accuracy. Thermal error compensation is an easy and economical way to reduce the thermal error. However, the effectiveness of compensation is highly dependent on the thermal error model. In this paper, the thermal characteristics of the spindle of a horizontal machining center are investigated and tested. The measured temperature changes during a period of time are reconstructed based on PCA and used as the new input variables rather than discrete temperatures collected at some certain moments for axial spindle thermal error modeling. By comparing with the thermal error model built on original temperature data, it finds out that the accuracy of spindle thermal error modeling and prediction are improve by adopting PCA for data processing. © 2018, Springer-Verlag London Ltd., part of Springer Nature.

Keyword :

Measured temperatures Spindle systems Spindle thermal errors Temperature changing Thermal characteristic analysis Thermal characteristics Thermal error compensation Thermal error modeling

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GB/T 7714 Li, Yang , Wei, Wenming , Su, Dongxu et al. Thermal error modeling of spindle based on the principal component analysis considering temperature-changing process [J]. | International Journal of Advanced Manufacturing Technology , 2018 , 99 (5-8) : 1341-1349 .
MLA Li, Yang et al. "Thermal error modeling of spindle based on the principal component analysis considering temperature-changing process" . | International Journal of Advanced Manufacturing Technology 99 . 5-8 (2018) : 1341-1349 .
APA Li, Yang , Wei, Wenming , Su, Dongxu , Zhao, Wanhua , Zhang, Jun , Wu, Wenwu . Thermal error modeling of spindle based on the principal component analysis considering temperature-changing process . | International Journal of Advanced Manufacturing Technology , 2018 , 99 (5-8) , 1341-1349 .
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Investigation of the dynamic electromechanical coupling due to the thrust harmonics in the linear motor feed system EI SCIE Scopus
期刊论文 | 2018 , 111 , 492-508 | MECHANICAL SYSTEMS AND SIGNAL PROCESSING
SCOPUS Cited Count: 2
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Abstract :

In the linear motor feed system, all the intermediate transmission components are cancelled. Lots of thrust harmonics caused by the nonlinearity of drive circuit and motor itself directly act on the mechanical system, leading to the vibrations. Meanwhile, the mechanical vibrations also affect the characteristics of motor thrust through the full closed-loop control. There is a close coupling between the servo drive and mechanical system, affecting the dynamic precision of the feed system. Therefore in this paper, an analytical method, which is used to present the mechanism of the electromechanical coupling caused by the thrust harmonics and its effects on the dynamic precision, is explored for the linear motor feed system. The thrust harmonics and mechanical characteristics are calculated firstly. The interactions between the servo system and mechanical system are analyzed afterwards. Then the coupled equation is established and the coupled process is analyzed. Moreover, the influence of the coupling on the displacement fluctuation is discussed. The results show that the thrust harmonics will produce significant displacement fluctuations, which is actually an electromechanical coupling process. In addition, its effects will aggravate with the increase of the velocity. At last several measures are put forward to improve the dynamic precision of the feed system. The displacement fluctuation caused by thrust harmonics is decreased more than 90% by implementing an integrated compensation strategy. This work will provide the theoretical support for the analysis and optimization of the complex electromechanical couplings, especially for the linear motor feed system. (C) 2018 Elsevier Ltd. All rights reserved.

Keyword :

Displacement fluctuation Mechanical vibration Electromechanical coupling Thrust harmonics Linear motor feed system

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GB/T 7714 Yang, Xiaojun , Liu, Hui , Lu, Dun et al. Investigation of the dynamic electromechanical coupling due to the thrust harmonics in the linear motor feed system [J]. | MECHANICAL SYSTEMS AND SIGNAL PROCESSING , 2018 , 111 : 492-508 .
MLA Yang, Xiaojun et al. "Investigation of the dynamic electromechanical coupling due to the thrust harmonics in the linear motor feed system" . | MECHANICAL SYSTEMS AND SIGNAL PROCESSING 111 (2018) : 492-508 .
APA Yang, Xiaojun , Liu, Hui , Lu, Dun , Zhao, Wanhua . Investigation of the dynamic electromechanical coupling due to the thrust harmonics in the linear motor feed system . | MECHANICAL SYSTEMS AND SIGNAL PROCESSING , 2018 , 111 , 492-508 .
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Decoupling and effects of the mechanical vibration on the dynamic precision for the direct-driven machine tool EI SCIE Scopus
期刊论文 | 2018 , 95 (9-12) , 3243-3258 | INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
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Abstract :

The linear motor feed system realizes direct drive, and all the intermediate transmission components are canceled. The thrust harmonics and other disturbances act on the mechanical system directly because the mover is connected with the driven parts, leading to obvious mechanical vibrations. The mechanical dynamic characteristics have important effects on the thrust characteristics and dynamic precision of linear motor feed system. In this paper, the decoupling and effects of the mechanical vibration on the dynamic precision for the direct driven are researched. Firstly, the mechanical kinetic model is established considering the characteristics of the joint between the guide rail and block and servo stiffness. Then the model realizes decoupling through the modal analysis, and the vibration responses in different directions are analytically calculated. What is more, a modeling method for the linear motor feed system considering the mechanical characteristic is put forward based on the modal separation method (MSM). The effects of the mechanical vibration on the dynamic precision of feed system are discussed. At last, the experiments are carried out and the influences of the structure parameters on the mechanical characteristics and displacement fluctuations are analyzed through sensitivity analysis, which provides a theoretical basis for the mechanical active design and improvement.

Keyword :

Sensitivity analysis Modal separation method Mechanical system Dynamic precision Linear motor feed system

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GB/T 7714 Yang, Xiaojun , Lu, Dun , Zhao, Wanhua . Decoupling and effects of the mechanical vibration on the dynamic precision for the direct-driven machine tool [J]. | INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY , 2018 , 95 (9-12) : 3243-3258 .
MLA Yang, Xiaojun et al. "Decoupling and effects of the mechanical vibration on the dynamic precision for the direct-driven machine tool" . | INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 95 . 9-12 (2018) : 3243-3258 .
APA Yang, Xiaojun , Lu, Dun , Zhao, Wanhua . Decoupling and effects of the mechanical vibration on the dynamic precision for the direct-driven machine tool . | INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY , 2018 , 95 (9-12) , 3243-3258 .
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Electromechanical integrated modeling and analysis for the direct-driven feed system in machine tools EI SCIE Scopus
期刊论文 | 2018 , 98 (5-8) , 1591-1604 | INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
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Abstract :

The permanent magnet linear synchronous motor (PMLSM) feed system realizes the direct drive. All the intermediate mechanical transmission parts are canceled and then the motor mover is directly connected with the driven components. The interaction between servo system and mechanical system becomes more close and complex, affecting the dynamic performance of the direct-driven feed system. In this paper, the dynamic characteristics of the drive circuit, PMLSM, control loops, and mechanical system are analyzed, and then an electromechanical integrated modeling method for the direct-driven feed system is proposed. Firstly, the dynamic precision of the feed system and electromechanical analytical model is studied. Then the nonlinearities of the drive circuit and PMLSM are researched. The analytical expression of the motor thrust is derived. What is more, the mechanical dynamic model is set up using the Lagrange equation and the main forms of the vibrations are discussed. Finally, the electromechanical integrated model is established and the experiments are carried out to verify the theoretical results. The results show that the proposed integrated modeling method can accurately represent the dynamic precision of the direct-driven feed system, which can provide the theoretical foundation for analyzing the electromechanical couplings and compensation methods.

Keyword :

Servo system Direct-driven feed system Electromechanical integrated model Dynamic precision Mechanical system

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GB/T 7714 Yang, Xiaojun , Lu, Dun , Liu, Hui et al. Electromechanical integrated modeling and analysis for the direct-driven feed system in machine tools [J]. | INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY , 2018 , 98 (5-8) : 1591-1604 .
MLA Yang, Xiaojun et al. "Electromechanical integrated modeling and analysis for the direct-driven feed system in machine tools" . | INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 98 . 5-8 (2018) : 1591-1604 .
APA Yang, Xiaojun , Lu, Dun , Liu, Hui , Zhao, Wanhua . Electromechanical integrated modeling and analysis for the direct-driven feed system in machine tools . | INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY , 2018 , 98 (5-8) , 1591-1604 .
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