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DETERMINATION OF PRESSURIZING CURVE AND COMPUTER CONTROL OF THICKNESS THINNING FOR SUPERPLASTIC BULGING
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作者 张中元 黄翔 +1 位作者 周建华 王卫英 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第1期30-38,共9页
This paper proposes the assumption that the flow with viscous friction is the stretch of part of the sheet that lies along the walls of a die during the process of superplastic bulging according to superplastic flow e... This paper proposes the assumption that the flow with viscous friction is the stretch of part of the sheet that lies along the walls of a die during the process of superplastic bulging according to superplastic flow equation and geometrical model of bulging of a sheet into a long trapezoid groove or truncated cone, by introducing the friction-factor P which describes the friction effect on the process. Also, the paper proposes the method of controlling thickness nonuniformity and develops the equipment which for uniform thickness of bulging, is automatically controlled with a computerl it also analyzes the important innuence of lubrication on thickness distribution of bulging materials. By the assumption, the relationship between bulging pressure and time is obtained in bulging of a sheet into the groove and cone, and p-t curve of multi-mould-cavity complicated bulging is discussed based on the analysis of single-mould-cavity bulging characteristics. 展开更多
关键词 superplastic forming computer control friction-factor thinning-rate pressure curve superplastic bulging
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Microcomputer Controlled High Precision Image Scanning Systems for Railway Tunnel Width Measurement
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作者 何广存 杨位钦 《Journal of Beijing Institute of Technology》 EI CAS 1995年第1期52+48-52,共6页
There should be high resolution demand that is better than 1000 DPI(dot per inch) for high precision image scanning system. This paper introduced the two-level computer controlled system that consisted of LS-3500 film... There should be high resolution demand that is better than 1000 DPI(dot per inch) for high precision image scanning system. This paper introduced the two-level computer controlled system that consisted of LS-3500 film scanner, AST386/33 monitoring control level and Intel 8031 single chip computer that is used as DDC level. The formula for scanning image data processing and methods of statistic parameters calculating are described. 展开更多
关键词 computer control linear transforms image resolution scanning systems
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TK7 High-Temperature Tunnel Kiln Computer Control System of SRIC Thailand
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作者 QIN Shukai YANG Yinghua +3 位作者 CHEN Xiaobo ZHANG Yazhong BU Youkang GUO Xiaojun 《China's Refractories》 CAS 2007年第1期15-18,共4页
Based on the TK7 high-temperature tunnel kiln computer control system, this article describes the control line system, the automatic loop control which has been realized in firing zone temperature, inner and bottom pr... Based on the TK7 high-temperature tunnel kiln computer control system, this article describes the control line system, the automatic loop control which has been realized in firing zone temperature, inner and bottom pressure and flow, and logic control of kiln doors and pusher, etc. In addition, this system integrates the product information management system of magnesite brick and efficiently ensures the important process parameters. During three months performance of the control system, all parameters and energy consumption have turned out a good result. 展开更多
关键词 High-temperature tunnel kiln computer control system Product information management
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Computer Network Control System in Automatic Automobile Detection
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作者 高岩 窦丽华 +1 位作者 高琪 周宁 《Journal of Beijing Institute of Technology》 EI CAS 2001年第4期406-411,共6页
An automobile test controlling and managing system with computer network is introduced. The architecture of the local network, hardware structure, software structure, design of the test process, and error tolerating r... An automobile test controlling and managing system with computer network is introduced. The architecture of the local network, hardware structure, software structure, design of the test process, and error tolerating redundant design in work position substituting are presented. At last, the pivotal questions solved are discussed. With an advanced structure, this system is multi functional and flexible. Furthermore, advanced computer technology is adopted to improve its technical degree. 展开更多
关键词 computer control system local network automobile test error tolerance
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A Computer-Controlled Polishing Machine
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作者 辛企明 《Journal of Beijing Institute of Technology》 EI CAS 1994年第2期162-169,共8页
Describes a computer controlled polishing machine utilizing a small polisher with specified movement to figure optical surfces having strict dimensional requirements. The system is especially applicable in figuring as... Describes a computer controlled polishing machine utilizing a small polisher with specified movement to figure optical surfces having strict dimensional requirements. The system is especially applicable in figuring aspherical surfaces, beginning with the best fit sphere if the departure from the desired surface is not large. An interferometric measuring system is desiigned to form a closed loop control during processing. 展开更多
关键词 polishing(surface finishing) computer control
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Study of weighted space deconvolution algorithm in computer controlled optical surfacing formation 被引量:5
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作者 李洪玉 张伟 Guoyu Yu 《Chinese Optics Letters》 SCIE EI CAS CSCD 2009年第7期627-631,共5页
Theoretical and experimental research on the deconvolution algorithm of dwell time in the technology of computer controlled optical surfacing (CCOS) formation is made to get an ultra-smooth surface of space optical ... Theoretical and experimental research on the deconvolution algorithm of dwell time in the technology of computer controlled optical surfacing (CCOS) formation is made to get an ultra-smooth surface of space optical element. Based on the Preston equation, the convolution model of CCOS is deduced. Considering the morbidity problem of deconvolution algorithm and the actual situation of CCOS technology, the weighting spatial deconvolution algorithm is presented based on the non-periodic matrix model, which avoids solving morbidity resulting from the noise induced by measurement error. The discrete convolution equation is solved using conjugate gradient iterative method and the workload of iterative calculation in spatial domain is reduced effectively. Considering the edge effect of convolution algorithm, the method adopts a marginal factor to control the edge precision and attains a good effect. The simulated processing test shows that the convergence ratio of processed surface shape error reaches 80%. This algorithm is further verified through an experiment on a numerical control bonnet polishing machine, and an ultra- smooth glass surface with the root-mean-square (RMS) error of 0.0088 tim is achieved. The simulation and experimental results indicate that this algorithm is steady, convergent, and precise, and it can satisfy the solving requirement of actual dwell time. 展开更多
关键词 ALGORITHMS computer control systems Conjugate gradient method CONVOLUTION POLISHING
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A computer control system for automatic TIG welding of aluminium alloy sheets
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作者 LIU Huijie ZHANG Jiuhai and L U Shixiong(Welding Department,Harbin Institute of Technology, Harbin,150001,China.) 《China Welding》 EI CAS 1996年第2期109-117,共9页
Aimed at the welding ttechnological requirements of foe missile shell,a computer control system for automatic TIG welding of aluminium alloy sheets has been developed in this paper.The hardware of the system is compos... Aimed at the welding ttechnological requirements of foe missile shell,a computer control system for automatic TIG welding of aluminium alloy sheets has been developed in this paper.The hardware of the system is composed of the four sub-systems,i.e.weldingpower source,arc length controller,welding wire feeder and welding head traveller.The software of the system comprises the on-line executing program and the off-line serving program.The operating principle,specifications and control of the system are introduced.The experiments indicate that the system possesses rational hardware structure and practical software function,and has solved the problem of high frequency interference to the computer control system. Therefore,the control system can satisfy the requirements of automatic TIG welding of the missile shell. 展开更多
关键词 computer control high frequency interference automatic TIG welding aluminium alloy sheet
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COMPUTER SIMULATION OF DIRECT TORQUE CONTROL SYSTEM
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作者 Hu Yuwen Xu Yue(Department of Automatic Control,NUAA 29 Yudao Street,Nanjing 210016,P.R.China) 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1994年第2期189-193,共5页
Computer simulation researches on Direct Torque Control System (DTC) are to be done. That fact is demonstrated:at high speed,the operating property of an induction motor is very good,almost the same as fieldoriented c... Computer simulation researches on Direct Torque Control System (DTC) are to be done. That fact is demonstrated:at high speed,the operating property of an induction motor is very good,almost the same as fieldoriented control system fat low speed (for example: below 2-3Hz), the operating property of a motor is getting worse,and the stator resistance R1 of the motor must be compensated. If compensation precision gets 5 %,the operating property of the motor will be greatly improved. 展开更多
关键词 computerIZED SIMULATION SPEED control SYSTEM motors
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A NEW CONTROL METHOD FOR ULTRASONIC MOTOR 被引量:1
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作者 魏守水 赵向东 赵淳生 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第2期109-113,共5页
A new method for the control of the speed of an ultrasonic motor and its implementation are proposed. The method is merely used by detecting the time when motor′s monitor signal reaches a non zero reference valu... A new method for the control of the speed of an ultrasonic motor and its implementation are proposed. The method is merely used by detecting the time when motor′s monitor signal reaches a non zero reference value than a zero one, the direction, in which the driving frequency of the motor should be shifted, can be promptly calculated. With the aid of a CPU and the phase locked frequency doubling technique, the motor can be steadily driven in a wide range of frequency and the optimum frequency can be captured rapidly and precisely. Experiment shows that the above method is available. 展开更多
关键词 ultrasonic motor computer control piezoelectric actuator phase locked loop speed control
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INTEGRATION OF GENERIC SHOP FLOOR CONTROL
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作者 叶文华 王宁生 +1 位作者 朱锦标 谭惠民 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第1期96-101,共6页
Based on the discussion of functions, components, control structure and network computing architecture of generic shop floor control (GSFC) in computer integrated manufacturing system (CIMS), the internal integrati... Based on the discussion of functions, components, control structure and network computing architecture of generic shop floor control (GSFC) in computer integrated manufacturing system (CIMS), the internal integration between components of GSFC and the external integration between GSFC and the other components of CIMS are studied. The integration models on the aspects of function, information, processing and interface are put forward. The integration models and the methods are implemented and applied in CIMS projects successfully. 展开更多
关键词 computer aided manufacturing AUTOMATION computer control shop floor control INTEGRATION
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基于计算机的蓄热式加热炉燃烧过程控制系统研究
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作者 刘一鸥 《工业加热》 CAS 2024年第10期31-34,共4页
随着工业生产和能源需求的不断增长,工业领域正经历着巨大的变革。在此背景下,热处理和加热炉的设计和操作变得至关重要,因为它们直接影响到生产过程的效率和环境可持续性。蓄热式加热炉是热处理工业中的重要设备,广泛应用于钢铁、有色... 随着工业生产和能源需求的不断增长,工业领域正经历着巨大的变革。在此背景下,热处理和加热炉的设计和操作变得至关重要,因为它们直接影响到生产过程的效率和环境可持续性。蓄热式加热炉是热处理工业中的重要设备,广泛应用于钢铁、有色金属和其他行业。其燃烧过程的控制对产品质量、能源利用效率和环境保护至关重要。对基于计算机的蓄热式加热炉燃烧过程控制系统进行了深入研究和分析。探讨了蓄热式加热炉结构以及特点,分析蓄热式加热炉燃烧控制策略,并从温度前馈双交叉限幅燃烧控制系统设计以及板坏温度预报模型介绍结合了基于计算机控制的蓄热式加热炉设计方法,能够帮助工业企业以应对不断变化的工业需求和环境法规,推动热处理工业的可持续发展。 展开更多
关键词 蓄热式加热炉 燃烧过程 计算机控制 系统设计
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嵌入式实时控制三轴数控滑台实验平台的构建
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作者 蔺凤琴 贾瑞哲 +3 位作者 李擎 郭金 李香泉 车伟杰 《实验室研究与探索》 CAS 北大核心 2024年第1期61-66,72,共7页
为进一步提升嵌入式技术的实验教学水平,培养学生运用嵌入式技术解决实际复杂工程问题的能力,构建了嵌入式实时控制三轴数控滑台实验平台。该平台支持定制、固化软件的离线下载,集成了实时参数调节功能,可对三轴运行实时进行参数修改,... 为进一步提升嵌入式技术的实验教学水平,培养学生运用嵌入式技术解决实际复杂工程问题的能力,构建了嵌入式实时控制三轴数控滑台实验平台。该平台支持定制、固化软件的离线下载,集成了实时参数调节功能,可对三轴运行实时进行参数修改,以获取最佳运行轨迹。实验运行结果表明:采用次平滑型S型电动机加速控制,实现了三轴协同运动,同时完成了复杂的滴胶运动;采用三轴圆弧和直线插补运动,定位精度达±0.01 mm,领先于同类产品。该平台还提供了基于Android Studio研发的移动端APP,支持MODBUS-TCP/IP协议的以太网、WiFi通信以及MODBUS-RTU协议的蓝牙通信,APP可实现平台的远程连接、操作功能,使学生开展实验更加方便快捷。 展开更多
关键词 嵌入式 三轴数控滑台 实时控制 实验平台
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Mathematical Model of Dynamic Operation and Optimum Control of Billet Reheating Furnace 被引量:1
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作者 刘日新 宁宝林 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1992年第4期279-283,共5页
This paper provides a mathematical model for the billet reheating process in furnace.A new optimum method is brought up that the objective function is the integral value of enthalpy increasing process of a billet.Diff... This paper provides a mathematical model for the billet reheating process in furnace.A new optimum method is brought up that the objective function is the integral value of enthalpy increasing process of a billet.Different delays are simulated and calculated,some proper delay strategies are ob- tained.The on-line computer control model is de- veloped.The real production conditions simulated, the temperature deviation of drop out billet from the target temperature is kept within±15℃. 展开更多
关键词 reheating furnace enthalpy increasing process delay strategy on-line computer control mathematical model
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Automatic Control System of Ion Electrostatic Accelerator and Anti-Interference Measures 被引量:1
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作者 孙振武 霍裕平 +2 位作者 刘根成 李玉晓 李涛 《Plasma Science and Technology》 SCIE EI CAS CSCD 2007年第1期101-105,共5页
An automatic control system for the electrostatic accelerator has been developed by adopting the PLC (Programmable Logic Controller) control technique, infrared and optical-fibre transmission technique and network c... An automatic control system for the electrostatic accelerator has been developed by adopting the PLC (Programmable Logic Controller) control technique, infrared and optical-fibre transmission technique and network communication with the purpose to improve the intelligence level of the accelerator and to enhance the ability of monitoring, collecting and recording parameters. In view of the control system' structure, some anti-interference measures have been adopted after analyzing the interference sources. The measures in hardware include controlling the position of the corona needle, using surge arresters, shielding, ground connection and stabilizing the voltage. The measures in terms of software involve inter-blocking protection, soft-spacing, time delay, and diagnostic and protective programs. The electromagnetic compatible ability of the control system has thus been effectively improved. 展开更多
关键词 electrostatic accelerator computer control SOFTWARE HARDWARE electromag- netic interference
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基于ResNet多特征图融合的钻削表面粗糙度分类方法
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作者 陈刚 彭望 +2 位作者 王闻宇 赵海军 程浩 《机电工程》 CAS 北大核心 2024年第9期1613-1627,共15页
传统五面复合数控(CNC)钻削表面粗糙度测量工作复杂,采用人工测量存在较大人为误差。传统多元回归、多项式拟合方法仅采用转速和进给速度参数,数据利用率低且噪声敏感性强;用传统机器学习方法无法有效提取信号的深层复杂特征。针对上述... 传统五面复合数控(CNC)钻削表面粗糙度测量工作复杂,采用人工测量存在较大人为误差。传统多元回归、多项式拟合方法仅采用转速和进给速度参数,数据利用率低且噪声敏感性强;用传统机器学习方法无法有效提取信号的深层复杂特征。针对上述问题,提出了一种基于ResNet模型、频谱图特征与时频图特征融合的钻削表面粗糙度分类预测方法。首先,根据CNC钻削加工理论和企业实际CNC钻削经验确定了CNC钻削加工实验的工艺参数变量;然后,基于SYNTEC CNC系统开发了多源数据采集系统,实时采集了钻削加工过程数据;接着,分析了三轴振动信号的频谱特征和时频特征,验证了振动信号跟表面粗糙度类别的关联性;随后,采用卡尔曼滤波对三轴振动信号进行了降噪处理,采用快速傅里叶变换(FFT)和连续小波变换(CWT)进行了振动信号频谱热图与时频图转换,采用矩阵拼接对三轴振动信号的单轴时频图进行了拼接融合,得到了三轴振动时频图;最后,对频谱热图和时频图进行了卷积运算融合频谱特征与时频特征,并进行了ResNet和其他网络模型如Densenet、Shufflenet和Mobilenet_v3_small等的对比实验。研究结果表明:相对上述其他网络模型,基于ResNet网络模型的表面粗糙度分类正确率提高了约9%,同时也验证了三轴时频特征融合以及频谱特征和时频特征融合方法的正确性。由于模型训练成本低、训练收敛速度快,该方法在轻量级、低成本的CNC机床钻削表面粗糙度预测分类中具有良好的工业应用前景。 展开更多
关键词 智能制造 数控机床 数据采集 SYNTEC数控系统 表面粗糙度分类 快速傅里叶变换 连续小波变换
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结合作答时间的自适应测验组卷方法
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作者 李弘 罗照盛 喻晓锋 《南昌大学学报(理科版)》 CAS 2024年第4期384-395,共12页
随着信息技术发展和计算机化自适应测验应用的普及,作答时间数据作为测验过程信息越来越容易获得,在心理测量领域的应用越来越广泛。将作答时间及模型应用于自动化组卷,对提高测验效率、被试能力估计精度乃至教育公平都有非常重要的意... 随着信息技术发展和计算机化自适应测验应用的普及,作答时间数据作为测验过程信息越来越容易获得,在心理测量领域的应用越来越广泛。将作答时间及模型应用于自动化组卷,对提高测验效率、被试能力估计精度乃至教育公平都有非常重要的意义。本文通过对自适应测验中组卷方法及研究结果进行系统梳理,全面展示结合作答时间数据的组卷方法,探究该类组卷方法对测验总时间约束、测验效率、题库安全、被试作答时间差异等问题的解决方案。对结合作答时间数据的组卷方法进行拓展,以及将研究成果应用于我国的大规模测评项目,都是未来需要探索的重要研究方向。 展开更多
关键词 作答时间 自动化组卷 计算机化自适应测验 曝光控制 终止规则
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Computation Method for the Real-Time Control Problems in Differential-Algebraic Systems
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作者 Fei, Jinggao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第2期20-28,共9页
In this paper, a real-time computation method for the control problems in differential-algebraic systems is presented. The errors of the method are estimated, and the relation between the sampling stepsize and the con... In this paper, a real-time computation method for the control problems in differential-algebraic systems is presented. The errors of the method are estimated, and the relation between the sampling stepsize and the controlled errors is analyzed. The stability analysis is done for a model problem, and the stability region is ploted which gives the range of the sampling stepsizes with which the stability of control process is guaranteed. 展开更多
关键词 ALGEBRA Computational complexity computer control systems Error analysis Mathematical models Process engineering Production engineering Real time systems Sampling System stability
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Transfer Function Model of Multirate Feedback Control Systems
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作者 肖建 唐磊 《Journal of Modern Transportation》 2001年第1期1-7,共7页
Based on the suitably defined multivariable version of Kranc operators and the extended input and output vectors, the multirate sampling plant is transformed to a equivalent time invariant single rate one, then the t... Based on the suitably defined multivariable version of Kranc operators and the extended input and output vectors, the multirate sampling plant is transformed to a equivalent time invariant single rate one, then the transfer function model of the multivariable multirate sampling plant is obtained. By combining this plant model with the time invariant description of the multirate controller in terms of extended vectors, the closed loop transfer function model of the multirate feedback control system can be determinated. This transfer function model has a very simple structure, and can be used as a basis for the analysis and synthesis of the multirate sampling feedback control systems in the frequency domain. 展开更多
关键词 feedback control transfer functions multirate digital control systems computer control
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CAT分层类曝光控制策略研究新进展
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作者 刘海东 虞芷筠 +3 位作者 李浩 秦春影 杨建芹 喻晓锋 《江西师范大学学报(自然科学版)》 CAS 北大核心 2024年第2期139-146,共8页
计算机化自适应测验(computerized adaptive testing,CAT)可以根据每一名考生的不同作答进行自适应选题,提高了测验精度.但高精度也伴随着高曝光风险,分层类项目曝光控制策略作为项目曝光控制的方法之一,是近年来曝光控制研究领域的热点... 计算机化自适应测验(computerized adaptive testing,CAT)可以根据每一名考生的不同作答进行自适应选题,提高了测验精度.但高精度也伴随着高曝光风险,分层类项目曝光控制策略作为项目曝光控制的方法之一,是近年来曝光控制研究领域的热点.同时,反应时(RT)的收集是CAT的一大优势,RT对于测验的实施具有重要价值.该文综合介绍了传统的分层策略,并结合RT的分层策略探讨当前分层策略应用于CAT项目曝光控制中存在的问题及其未来研究方向. 展开更多
关键词 计算机化自适应测验 反应时 项目曝光控制 分层策略 测验时间 选题策略
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基于五轴数控机床的复杂曲面加工研究
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作者 李丹 《现代制造技术与装备》 2024年第10期110-112,共3页
近年来,复杂曲面零件的加工需求日益增长。深入研究基于五轴数控机床的复杂曲面加工技术,首先详细阐述五轴数控机床的工作原理,其次分析复杂曲面加工的难点,最后着重探讨工件装夹定位、刀具路径规划、加工参数设置和后处理等关键的复杂... 近年来,复杂曲面零件的加工需求日益增长。深入研究基于五轴数控机床的复杂曲面加工技术,首先详细阐述五轴数控机床的工作原理,其次分析复杂曲面加工的难点,最后着重探讨工件装夹定位、刀具路径规划、加工参数设置和后处理等关键的复杂曲面加工工艺要点。对比实验结果表明,五轴加工在形状精度、表面质量、加工效率和刀具寿命等方面具有显著优势。 展开更多
关键词 五轴数控机床 复杂曲面 加工工艺
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