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MOTION ERROR ESTIMATION OF 5-AXIS MACHINING CENTER USING DBB METHOD 被引量:3
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作者 CHEN Huawei ZHANG Dawei +1 位作者 TIAN Yanling ICHIR0 Hagiwara 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第2期276-281,共6页
In order to estimate the motion errors of 5-axis machine center, the double ball bar (DBB) method is adopted to realize the diagnosis procedure. The motion error sources of rotary axes in 5-axis machining center com... In order to estimate the motion errors of 5-axis machine center, the double ball bar (DBB) method is adopted to realize the diagnosis procedure. The motion error sources of rotary axes in 5-axis machining center comprise of the alignment error of rotary axes and the angular error due to various factors, e.g. the inclination of rotary axes. From sensitive viewpoints, each motion error is possible to have a particular sensitive direction in which deviation of DBB error trace arises from only some specific error sources. The model of the DBB error trace is established according to the spatial geometry theory. Accordingly, the sensitive direction of each motion error source is made clear through numerical simulation, which is used as the reference patterns for rotational error estimation. The estimation method is proposed to easily estimate the motion error sources of rotary axes in quantitative manner. To verify the proposed DBB method for rotational error estimation, the experimental tests are carried out on a 5-axis machining center M-400 (MORISEIKI). The effect of the mismatch of the DBB is also studied to guarantee the estimation accuracy. From the experimental data, it is noted that the proposed estimation method for 5-axis machining center is feasible and effective. 展开更多
关键词 5-axis NC machine tool Double ball bar(DBB) Motion errors of rotary axes
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A Real-time NURBS Surface Interpolator for 5-axis Surface Machining 被引量:2
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作者 王永章 陈良骥 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2005年第3期263-272,共10页
A real-time non-uniform rational B-spline (NURBS) surface interpolator is proposed and 5-axis machining method with a flat-end cutter is discussed. With the Taylor expansion and the coordinate transformation, the al... A real-time non-uniform rational B-spline (NURBS) surface interpolator is proposed and 5-axis machining method with a flat-end cutter is discussed. With the Taylor expansion and the coordinate transformation, the algorithms of NURBS interpolation, cutter effective machining radius, cutter offsetting and.inverse kinematics are deduced and implemented, respectively. Different from the conventional free-form surface machining, the proposed interpolator can real-time generate the motion commands of computer numerical control (CNC) machines with CC feedrate, rather than that of CL. An example part surface is demonstrated and the results of simulation show that the proposed method can be applied in actual 5-axis surface machining. 展开更多
关键词 free-form surface real-time interpolator NURBS 5-axis machining
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Development of tool-path generation module for 5-axis control machining of impellers 被引量:3
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作者 JUNG Hyoun-chul SON Hwang-jin JUNG Yoon-gyo 《Journal of Central South University》 SCIE EI CAS 2012年第12期3424-3429,共6页
An impeller is difficult to machine because of severe collision due to the complex shape,overlapping and twisted shape of the impeller blades.So,most computer aided manufacturing(CAM)software companies have developed ... An impeller is difficult to machine because of severe collision due to the complex shape,overlapping and twisted shape of the impeller blades.So,most computer aided manufacturing(CAM)software companies have developed CAM module for manufacturing impeller according to their CAM software.But these dedicated modules are difficult to use for inexperienced users.The purpose of this work is to develop a tool-path generation module for impellers.For this purpose,it is based on Visual Basic language and used CATIA graphical environment.The result of simulation for generated tool-path by the module is satisfactory.And it has slow processing speed compared to other commercial modules,but it is easy to use. 展开更多
关键词 IMPELLER computer aided manufacturing 5-axis control machining tool path MODULE
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Tool Orientation Optimization and Path Planning for 5-Axis Machining 被引量:3
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作者 YUAN Chunming MI Zhenpeng +2 位作者 JIA Xiaohong LIN Fengming SHEN Liyong 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2021年第1期83-106,共24页
Tool path generation is a fundamental problem in 5-axis CNC machining, which consists of tool orientation planning and cutter-contact(CC) point planning. The planning strategy highly depends on the type of tool cutter... Tool path generation is a fundamental problem in 5-axis CNC machining, which consists of tool orientation planning and cutter-contact(CC) point planning. The planning strategy highly depends on the type of tool cutters. For ball-end cutters, the tool orientation and CC point location can be planned separately;while for flat end cutters, the two are highly dependent on each other. This paper generates a smooth tool path of workpiece surfaces for flat end mills from two stages: Computing smooth tool orientations on the surface without gouging and collisions and then designing the CC point path. By solving the tool posture optimization problem the authors achieve both the path smoothness and the machining efficiency. Experimental results are provided to show the effectiveness of the method. 展开更多
关键词 5-axis CNC machining flat end cutter tool path planning tool posture optimization
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Optimization of cutter-location for 5-axis NC machining freeform surface with a flat-end cutter 被引量:1
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作者 任秉银 刘华明 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第4期30-33,共4页
axis NC machining freeform surface with a flat end cutter can theoretically improve material removal rate and surface finish, but it is very difficult to generate a gouge free cutter location. A new method of gener... axis NC machining freeform surface with a flat end cutter can theoretically improve material removal rate and surface finish, but it is very difficult to generate a gouge free cutter location. A new method of generating optimal cutter path is proposed to define the effective radius of a flat end cutter and determine the optimal step forward distance and step over distance. Thereby improving the NC machining efficiency and quality of freeform surfaces. 展开更多
关键词 freeform surfaces 5 AXIS NC machining CUTTER LOCATION OPTIMIZATION FLAT END CUTTER
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Development of practical postprocessor for 5-axis machine tool with non-orthogonal rotary axes 被引量:13
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作者 JUNG Hyoun-Chul HWANG Jong-Dae +1 位作者 PARK Ki-Beom JUNG Yoon-Gyo 《Journal of Central South University》 SCIE EI CAS 2011年第1期159-164,共6页
In order to develop a practical postprocessor for 5-axis machine tool,the general equations of numerically controlled(NC) data for 5-axis configurations with non-orthogonal rotary axes were exactly expressed by the in... In order to develop a practical postprocessor for 5-axis machine tool,the general equations of numerically controlled(NC) data for 5-axis configurations with non-orthogonal rotary axes were exactly expressed by the inverse kinematics,and a windows-based postprocessor written with Visual Basic was developed according to the proposed algorithm.The developed postprocessor is a general system suitable for all kinds of 5-axis machines with orthogonal and non-orthogonal rotary axes.Through implementation of the developed postprocessor and verification by a cutting simulation and machining experiment,the effectiveness of the proposed algorithm is confirmed.Compatibility is improved by allowing exchange of data formats such as rotational total center position(RTCP) controlled NC data,vector post NC data,and program object file(POF) cutter location(CL) data,and convenience is increased by adding the function of work-piece origin offset.Consequently,a practical post-processor for 5-axis machining is developed. 展开更多
关键词 post-processor 5-axis machining non-orthogonal rotary axes numerically controlled (NC) data CL data
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A Hybrid Machine Learning Approach for Improvised QoE in Video Services over 5G Wireless Networks
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作者 K.B.Ajeyprasaath P.Vetrivelan 《Computers, Materials & Continua》 SCIE EI 2024年第3期3195-3213,共19页
Video streaming applications have grown considerably in recent years.As a result,this becomes one of the most significant contributors to global internet traffic.According to recent studies,the telecommunications indu... Video streaming applications have grown considerably in recent years.As a result,this becomes one of the most significant contributors to global internet traffic.According to recent studies,the telecommunications industry loses millions of dollars due to poor video Quality of Experience(QoE)for users.Among the standard proposals for standardizing the quality of video streaming over internet service providers(ISPs)is the Mean Opinion Score(MOS).However,the accurate finding of QoE by MOS is subjective and laborious,and it varies depending on the user.A fully automated data analytics framework is required to reduce the inter-operator variability characteristic in QoE assessment.This work addresses this concern by suggesting a novel hybrid XGBStackQoE analytical model using a two-level layering technique.Level one combines multiple Machine Learning(ML)models via a layer one Hybrid XGBStackQoE-model.Individual ML models at level one are trained using the entire training data set.The level two Hybrid XGBStackQoE-Model is fitted using the outputs(meta-features)of the layer one ML models.The proposed model outperformed the conventional models,with an accuracy improvement of 4 to 5 percent,which is still higher than the current traditional models.The proposed framework could significantly improve video QoE accuracy. 展开更多
关键词 Hybrid XGBStackQoE-model machine learning MOS performance metrics QOE 5G video services
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Realization Methodology of a 5-axis Spline Interpolator in an Open CNC System 被引量:10
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作者 Wang Yongzhang Ma Xiongbo Chen Liangji Han Zhenyu 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第4期362-369,共8页
By making use of the advantages of non-uniform rational B-spline (NURBS) curves to represent spatial curves, an instruction format with double NURBS curves suitable for 5-axis coordinated real-time interpolation is ... By making use of the advantages of non-uniform rational B-spline (NURBS) curves to represent spatial curves, an instruction format with double NURBS curves suitable for 5-axis coordinated real-time interpolation is presented to replace the current 5-axis coordinated linear interpolation method defective in low-speed, low-accuracy and enormous numerical control (NC) files in sculptured surface machining. A generation procedure of the NC files with the presented format is introduced and the method to realize the interpolation in an open computer numerical control (CNC) system is developed by ourselves. These illustrated the feasibility of the proposed method and its capability of avoiding all the shortages of 5-axis linear interpolation method. 展开更多
关键词 open CNC system sculptured surface 5-axis machining NURBS INTERPOLATION
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A NEW ALGORITHM BASED ON TRIANGULATION FOR 5 AXIS MACHINING OF SCULPTURED SURFACES
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作者 王清辉 廖文和 +1 位作者 刘壮 周儒荣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期80+75-79,共6页
NC machining path of sculptured surfaces in CAD/CAM system plays an important role on manufacture. This paper describes a new algorithm for 5 axis machining of sculptured surfaces and the algorithm is interference fr... NC machining path of sculptured surfaces in CAD/CAM system plays an important role on manufacture. This paper describes a new algorithm for 5 axis machining of sculptured surfaces and the algorithm is interference free. The approach includes: (1) the tesselation of the parametric surfaces into triangles; (2) building topological relations among triangles;(3) 5 axis tool path generation; (4) interference detection and tool position correction. 展开更多
关键词 numerical control INTERFERENCE CAD/CAM NC machining sculptured surface 5 axis machining
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Circular Interpolation Algorithms of 5-Axis Simultaneous CNC System 被引量:3
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作者 ZHENG Kuijing~(1.2) SHANG BO~2 1.Mechanical Engineering College,Yanshan University,Qinhuangdao 066004,China 2.Research and Development Center,GSK CNC Equipment Co.,Ltd.,Guangzhou 510165,China 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S2期407-411,共5页
Spatial circular arc can be machined conveniently by a 5-axis NC machine tool.Based on the data sampling method,circular interpolation in two-dimensional plane is discussed briefly.The key is to solve the problem of c... Spatial circular arc can be machined conveniently by a 5-axis NC machine tool.Based on the data sampling method,circular interpolation in two-dimensional plane is discussed briefly.The key is to solve the problem of circular center ex- pressed in the workpiece coordinate system by means of the transformation matrix.Circular interpolation in three-dimensional space is analyzed in detail.The method of undetermined coefficient is used to solve the center of the spatial circle and the method of coor- dinate transformation is used to transform the spatial circle into the XY-plane.Circular arc in three-dimensional space can be ma- chined by the positional 5-axis machining and the conical surface can be machined by the continuous 5-axis machining.The velocity control is presented to avoid the feedrate fluctuation.The interpolation algorithms are tested by a simulation example and the inter- polation algorithms are proved feasible.The algorithms are applied to the 5-axis CNC system software. 展开更多
关键词 Index Terms-Circular INTERPOLATION 5-axis CNC
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Detection Collision Flows in SDN Based 5G Using Machine Learning Algorithms
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作者 Aqsa Aqdus Rashid Amin +3 位作者 Sadia Ramzan Sultan S.Alshamrani Abdullah Alshehri El-Sayed M.El-kenawy 《Computers, Materials & Continua》 SCIE EI 2023年第1期1413-1435,共23页
The rapid advancement of wireless communication is forming a hyper-connected 5G network in which billions of linked devices generate massive amounts of data.The traffic control and data forwarding functions are decoup... The rapid advancement of wireless communication is forming a hyper-connected 5G network in which billions of linked devices generate massive amounts of data.The traffic control and data forwarding functions are decoupled in software-defined networking(SDN)and allow the network to be programmable.Each switch in SDN keeps track of forwarding information in a flow table.The SDN switches must search the flow table for the flow rules that match the packets to handle the incoming packets.Due to the obvious vast quantity of data in data centres,the capacity of the flow table restricts the data plane’s forwarding capabilities.So,the SDN must handle traffic from across the whole network.The flow table depends on Ternary Content Addressable Memorable Memory(TCAM)for storing and a quick search of regulations;it is restricted in capacity owing to its elevated cost and energy consumption.Whenever the flow table is abused and overflowing,the usual regulations cannot be executed quickly.In this case,we consider lowrate flow table overflowing that causes collision flow rules to be installed and consumes excessive existing flow table capacity by delivering packets that don’t fit the flow table at a low rate.This study introduces machine learning techniques for detecting and categorizing low-rate collision flows table in SDN,using Feed ForwardNeuralNetwork(FFNN),K-Means,and Decision Tree(DT).We generate two network topologies,Fat Tree and Simple Tree Topologies,with the Mininet simulator and coupled to the OpenDayLight(ODL)controller.The efficiency and efficacy of the suggested algorithms are assessed using several assessment indicators such as success rate query,propagation delay,overall dropped packets,energy consumption,bandwidth usage,latency rate,and throughput.The findings showed that the suggested technique to tackle the flow table congestion problem minimizes the number of flows while retaining the statistical consistency of the 5G network.By putting the proposed flow method and checking whether a packet may move from point A to point B without breaking certain regulations,the evaluation tool examines every flow against a set of criteria.The FFNN with DT and K-means algorithms obtain accuracies of 96.29%and 97.51%,respectively,in the identification of collision flows,according to the experimental outcome when associated with existing methods from the literature. 展开更多
关键词 5G networks software-defined networking(SDN) OpenFlow load balancing machine learning(ML) feed forward neural network(FFNN) k-means and decision tree(DT)
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基于改进LeNet-5网络的堆芯燃料组件编码识别
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作者 吕伽奇 丁帅 +1 位作者 庞静珠 许小进 《东华大学学报(自然科学版)》 CAS 北大核心 2024年第2期121-128,共8页
在核电站堆芯核燃料组件水下组装作业中,需要通过视觉技术进行组件编码的识别以便准确定位组件的安装位置。针对水下环境中弱光照等问题导致了图像质量的降低,本文通过乘方增强算法、OSTU算法、CLAHE算法和拉普拉斯变换的方法来实现堆... 在核电站堆芯核燃料组件水下组装作业中,需要通过视觉技术进行组件编码的识别以便准确定位组件的安装位置。针对水下环境中弱光照等问题导致了图像质量的降低,本文通过乘方增强算法、OSTU算法、CLAHE算法和拉普拉斯变换的方法来实现堆芯燃料组件编码字符水下图像的增强。为了提高编码识别效果,提出了一种整合LeNet-5网络和支持向量机(SVM)的模型,在网络中添加BN(Batch Normalization)层与Dropout层来加速网络的运行速度,并改进Sigmoid函数,增加函数的平滑性,以此来减少梯度消失。实验表明,在自定义数据集上的验证准确率为99.82%,识别率为100%,相比于其他模型有显著的提升。 展开更多
关键词 编码识别 图像处理 CLAHE算法 LeNet-5 支持向量机(SVM)
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A Collaborative Machine Learning Scheme for Traffic Allocation and Load Balancing for URLLC Service in 5G and Beyond
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作者 Andreas G. Papidas George C. Polyzos 《Journal of Computer and Communications》 2023年第11期197-207,共11页
Key challenges for 5G and Beyond networks relate with the requirements for exceptionally low latency, high reliability, and extremely high data rates. The Ultra-Reliable Low Latency Communication (URLLC) use case is t... Key challenges for 5G and Beyond networks relate with the requirements for exceptionally low latency, high reliability, and extremely high data rates. The Ultra-Reliable Low Latency Communication (URLLC) use case is the trickiest to support and current research is focused on physical or MAC layer solutions, while proposals focused on the network layer using Machine Learning (ML) and Artificial Intelligence (AI) algorithms running on base stations and User Equipment (UE) or Internet of Things (IoT) devices are in early stages. In this paper, we describe the operation rationale of the most recent relevant ML algorithms and techniques, and we propose and validate ML algorithms running on both cells (base stations/gNBs) and UEs or IoT devices to handle URLLC service control. One ML algorithm runs on base stations to evaluate latency demands and offload traffic in case of need, while another lightweight algorithm runs on UEs and IoT devices to rank cells with the best URLLC service in real-time to indicate the best one cell for a UE or IoT device to camp. We show that the interplay of these algorithms leads to good service control and eventually optimal load allocation, under slow load mobility. . 展开更多
关键词 5G and B5G Networks Ultra Reliable Low Latency Communications (URLLC) machine Learning (ML) for 5G Temporal Difference Methods (TDM) Monte Carlo Methods Policy Gradient Methods
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Real-time 5-axis Spline Interpolation Method and Servo-controlling Structure of CNC System
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作者 Liangji Chen Xianzhang Feng Huiying Li 《通讯和计算机(中英文版)》 2010年第5期44-49,共6页
关键词 非均匀有理B样条 数控系统 实时插补 控制结构 插值方法 伺服 NURBS曲线 计算机辅助制造
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MTS-05 PDM多频代播机核心技术及应用
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作者 方少青 《电视技术》 2024年第7期144-146,150,共4页
深入探讨MTS-05 PDM 5 kW多频代播机的研发背景、核心技术、应用价值及其对广播技术领域的影响。在中波广播技术面临频率固定性和调频机制局限的挑战背景下,MTS-05 PDM 5 kW多频代播机作为技术创新的产物,通过集成复杂可编程逻辑器件(Co... 深入探讨MTS-05 PDM 5 kW多频代播机的研发背景、核心技术、应用价值及其对广播技术领域的影响。在中波广播技术面临频率固定性和调频机制局限的挑战背景下,MTS-05 PDM 5 kW多频代播机作为技术创新的产物,通过集成复杂可编程逻辑器件(Complex Programmable Logic Device,CPLD)逻辑频率选通技术、直接数字合成(Direct Digital Synthesizer,DDS)高频激励机制和智能多频网络切换技术,实现了多频次高效、安全播出。设备不仅克服了传统发射机的调频烦琐和空间限制问题,还提升了播出质量和安全播出效率,展示了智能化运维与资源优化的典范。 展开更多
关键词 MTS-05 PDM 5 kW多频代播机 高频激励机制 多频网络切换 智能监控管理
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整体叶轮5轴数控加工工艺仿真技术研究 被引量:3
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作者 夏雨 《模具制造》 2023年第2期56-59,共4页
分析了整体叶轮的造型轮廓和加工特点,依据叶轮的整体形状和加工工艺技术要求,确定了基于UG NX软件的5轴加工策略,生成刀路轨迹,并完成整体叶轮零件的数控仿真的加工。结果表明:经过加工工艺的优化,通过在5轴加工中心加工整体叶轮,零件... 分析了整体叶轮的造型轮廓和加工特点,依据叶轮的整体形状和加工工艺技术要求,确定了基于UG NX软件的5轴加工策略,生成刀路轨迹,并完成整体叶轮零件的数控仿真的加工。结果表明:经过加工工艺的优化,通过在5轴加工中心加工整体叶轮,零件的表面质量和加工效率得到全面提升,对叶轮类零件的加工有一定借鉴的意义。 展开更多
关键词 整体叶轮 5轴加工 UGNX 加工工艺 仿真技术
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EQUIVALENT NORMAL CURVATURE APPROACH MILLING MODEL OF MACHINING FREEFORM SURFACES 被引量:5
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作者 YI Xianzhong MA Weiguo +2 位作者 QIHaiying YAN Zesheng GAO Deli 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第3期52-57,共6页
A new milling methodology with the equivalent normal curvature milling model machining freeform surfaces is proposed based on the normal curvature theorems on differential geometry. Moreover, a specialized whirlwind m... A new milling methodology with the equivalent normal curvature milling model machining freeform surfaces is proposed based on the normal curvature theorems on differential geometry. Moreover, a specialized whirlwind milling tool and a 5-axis CNC horizontal milling machine are introduced. This new milling model can efficiently enlarge the material removal volume at the tip of the whirlwind milling tool and improve the producing capacity. The machining strategy of this model is to regulate the orientation of the whirlwind milling tool relatively to the principal directions of the workpiece surface at the point of contact, so as to create a full match with collision avoidance between the workpiece surface and the symmetric rotational surface of the milling tool. The practical results show that this new milling model is an effective method in machining complex three- dimensional surfaces. This model has a good improvement on finishing machining time and scallop height in machining the freeform surfaces over other milling processes. Some actual examples for manufacturing the freeform surfaces with this new model are given. 展开更多
关键词 Equivalent normal curvature milling model Whirlwind milling method Freeform surfaces 5-axis CNC machine Differential geometry
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Parameters Optimization of a Novel 5-DOF Gasbag Polishing Machine Tool 被引量:8
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作者 LI Yanbiao TAN Dapeng +2 位作者 WEN Donghui JI Shiming CAI Donghai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第4期680-688,共9页
The research on the parameters optimization for gasbag polishing machine tools, mainly aims at a better kinematics performance and a design scheme. Serial structural arm is mostly employed in gasbag polishing machine ... The research on the parameters optimization for gasbag polishing machine tools, mainly aims at a better kinematics performance and a design scheme. Serial structural arm is mostly employed in gasbag polishing machine tools at present, but it is disadvantaged by its complexity, big inertia, and so on. In the multi-objective parameters optimization, it is very difficult to select good parameters to achieve excellent performance of the mechanism. In this paper, a statistics parameters optimization method based on index atlases is presented for a novel 5-DOF gasbag polishing machine tool. In the position analyses, the structure and workspace for a novel 5-DOF gasbag polishing machine tool is developed, where the gasbag polishing machine tool is advantaged by its simple structure, lower inertia and bigger workspace. In the kinematics analyses, several kinematics performance evaluation indices of the machine tool are proposed and discussed, and the global kinematics performance evaluation atlases are given. In the parameters optimization process, considering the assembly technique, a design scheme of the 5-DOF gasbag polishing machine tool is given to own better kinematics performance based on the proposed statistics parameters optimization method, and the global linear isotropic performance index is 0.5, the global rotational isotropic performance index is 0.5, the global linear velocity transmission performance index is 1.012 3 m/s in the case of unit input matrix, the global rotational velocity transmission performance index is 0.102 7 rad/s in the case of unit input matrix, and the workspace volume is 1. The proposed research provides the basis for applications of the novel 5-DOF gasbag polishing machine tool, which can be applied to the modern industrial fields requiring machines with lower inertia, better kinematics transmission performance and better technological efficiency. 展开更多
关键词 5-DOF gasbag polishing machine tool evaluation index kinematics analyses parameter optimization
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Dual Drive Curve Tool Path Planning Method for 5-axis NC Machining of Sculptured Surfaces 被引量:12
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作者 徐汝锋 陈志同 +2 位作者 陈五一 吴献珍 朱剑军 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第4期486-494,共9页
The problem of finished surface being not first-order continuous commonly exists in machining sculptured surfaces with a torus cutter and some other types of cutters. To solve this problem, a dual drive curve tool pat... The problem of finished surface being not first-order continuous commonly exists in machining sculptured surfaces with a torus cutter and some other types of cutters. To solve this problem, a dual drive curve tool path planning method is proposed in this article. First, the maximum machining strip width of a whole tool path can be obtained through optimizing each tool position with multi-point machining (MPM) method. Second, two drive curves are then determined according to the obtained maximum machining strip width. Finally, the tool is positioned once more along the dual drive curve under the condition of tool path smoothness. A computer simulation and cutting experiments are carried out to testify the performance of the new method. The machined surface is measured with a coordinate measuring machine (CMM) to examine the machining quality. The results obtained show that this method can effectively eliminate sharp scallops between adjacent tool paths, keep tool paths smooth, and improve the surface machining quality as well as machining efficiency. 展开更多
关键词 dual drive curve tool path planning multi-point machining 5-axis sculptured surfaces numerical control (NC) machining
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Prediction of Seaward Slope Recession in Berm Breakwaters Using M5' Machine Learning Approach 被引量:1
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作者 Alireza Sadat HOSSEINI Mehdi SHAFIEEFAR 《China Ocean Engineering》 SCIE EI CSCD 2016年第1期19-32,共14页
In the design process of berm breakwaters, their front slope recession has an inevitable rule in large number of model tests, and this parameter being studied. This research draws its data from Moghim's and Shekari'... In the design process of berm breakwaters, their front slope recession has an inevitable rule in large number of model tests, and this parameter being studied. This research draws its data from Moghim's and Shekari's experiment results. These experiments consist of two different 2D model tests in two wave flumes, in which the berm recession to different sea state and structural parameters have been studied. Irregular waves with a JONSWAP spectrum were used in both test series. A total of 412 test results were used to cover the impact of sea state conditions such as wave height, wave period, storm duration and water depth at the toe of the structure, and structural parameters such as berm elevation from still water level, berm width and stone diameter on berm recession parameters. In this paper, a new set of equations for berm recession is derived using the M5' model tree as a machine learning approach. A comparison is made between the estimations by the new formula and the formulae recently given by other researchers to show the preference of new M5' approach. 展开更多
关键词 berm breakwater recession experimental data M5 model tree machine learning method
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