基于模态预测及敏度分析的机床动特性设计方法
|
摘要
为了提高机床的动态性能,以机床整机固有频率和频响函数振幅为目标,提出基于机床测试数据、进行试验模态分析及灵敏度计算的机床动态特性设计方法。方法首先提取机床测试数据建立机床结构原型模型,逐步计算机床大件结构和整机的固有频率对刚度、质量的灵敏度,确定结构薄弱环节;继而,对薄弱结构,采用模态预测和灵敏度分析方法设计计算,获取更合理的质量和刚度;之后,将设计分析结果输入LMS_Test.lab软件,借助软件完成对原型结构的模态修改,对修改后结构的动力学特性进行模态预测;最后,进行预测结果模态置信验证,确认模态预测的正确性,完整机床动态特性设计方法体系。将该方法应用于实际机床设计中,对比整机优化前后的频响函数曲线和仿真分析验证均证明,基于模态预测及灵敏度分析的机床动态特性设计方法完成的机床优化设计使得机床固有频率得到提高的同时振幅下降,机床的大件结构及整机的动态性能均有提升。
Based on machine test data, test mode analysis and sensitivity calculation, a design method is proposed to improve the dynamic performance of the machine tool, in which the natural frequencies of the machine tool and the amplitude of frequency response function are taken as the research objects. Firstly, the stiffness and mass sensitivity with respect to natural frequency are calculated to find weaknesses position of the structures, for the main components and the whole machine tool, respectively. Secondly, the more reasonable stiffness and mass are deduced based on the proposed method for the weaken structures. Thirdly, the improved scheme is modified by the LMS_Test.lab software and the reliability of the results is ensured by the modal analysis criterion(MAC). The method is applied to the machine tool design, and the simulation results show that the new machine tool dynamic performances are improved with the increased natural frequencies and the decreased amplitudes.
Based on machine test data, test mode analysis and sensitivity calculation, a design method is proposed to improve the dynamic performance of the machine tool, in which the natural frequencies of the machine tool and the amplitude of frequency response function are taken as the research objects. Firstly, the stiffness and mass sensitivity with respect to natural frequency are calculated to find weaknesses position of the structures, for the main components and the whole machine tool, respectively. Secondly, the more reasonable stiffness and mass are deduced based on the proposed method for the weaken structures. Thirdly, the improved scheme is modified by the LMS_Test.lab software and the reliability of the results is ensured by the modal analysis criterion(MAC). The method is applied to the machine tool design, and the simulation results show that the new machine tool dynamic performances are improved with the increased natural frequencies and the decreased amplitudes.
引文
[1]刘悦,汪劲松.基于轴承及导轨接触刚度的混联机床静刚度研究及优化[J].机械工程学报,2007,43(9):151-155.LIU Yue,WANG Jinsong.Static stiffness research and optimization on a hybrid machine tool considering the stiffnesses of bearings and guideways[J].Chinese Journal of Mechanical Engineering,2007,43(9):151-155.
[2]李天箭,丁晓红,程凯.基于空间统计学的机床动力学特性[J].机械工程学报,2015,51(21):87-94.LI Tianjian,DING Xiaohong,CHENG Kai.Machine tool dynamics based on spatial statistics[J].Journal of Mechanical Engineering,2015,51(21):87-94.
[3]王信锐.数控机床能量模型及其应用研究[D].大连:大连理工大学,2013.WANG Xinrui.Energy model of CNC machine tool and its application research[D].Dalian:Dalian University of Technology,2013.
[4]郭垒,张辉,叶佩青,等.基于灵敏度分析的机床轻量化设计[J].清华大学学报,2011,51(6):846-850.GUO Lei,ZHANG Hui,YE Peiqing,et al.Lightweight design of machine tools based on sensitivity analysis[J].Journal of Tsinghua University,2011,51(6):846-850.
[5]DING Ye,ZHU Limin,ZHANG Xiaojian,et al.Response sensitivity analysis of the dynamic milling process based on the numerical integration method[J].Chinese Journal of Mechanical Engineering,2012,25(5):940-946.
[6]ZHAO Liping,CHEN Hongren,YAO Yiyong,et al.Anew approach to improving the machining precision based on dynamic sensitivity analysis[J].International Journal of Machine Tools and Manufacture,2016,102:9-21.
[7]廖伯瑜.现代机械动力学及其工程应用[M].北京:机械工业出版社,2003.LIAO Boyu.Modern mechanical dynamics and application[M].Beijing:China Machine Press,2003.
[8]LAW M,ALTINTAS Y,PHANI S.Rapid evaluation and optimization of machine tools with position-dependent stability[J].International Journal of Machine Tools and Manufacture,2013,68:81-90.
[9]邓聪颖,殷国富,方辉,等.基于正交试验的机床结合部动刚度优化配置[J].机械工程学报,2015,51(19):146-153.DENG Congying,YIN Guofu,FANG Hui,et al.Optimal configuration of dynamic stiffness of machine tool joints based on orthogonal experiment[J].Journal of Mechanical Engineering,2015,51(19):146-153.
[10]MAO Xinyong,LUO Bo,LI Bin,et al.An approach for measuring the FRF of machine tool structure without knowing any input force[J].International Journal of Machine Tools and Manufacture,2014,86:62-67.
[11]刘鲁宁.高速面铣刀模态参数及其对切削性能影响研究[D].济南:山东大学,2013.LIU Luning.Research on modal parameters and its influence on cutting performance of high speed milling cutter[D].Jinan:Shandong University,2013.
[12]ZAGHBANI I,SONGMENE V.Estimation of machine-tool dynamic parameters during machining operation through operational modal analysis[J].International Journal of Machine Tools and Manufacture,2009,49(12-13):947-957.
[13]张兴朝.基于有限元分析的模块化数控机床结构动态设计研究[D].天津:天津大学,2001.ZHANG Xingchao.Dynamic design of modular CNCmachine tools based on finite element analysis[D].Tianjin:Tianjin University,2001.
[14]LI Bin,LUO Bo,MAO Xinyong,et al.A new approach to identifying the dynamic behavior of CNC machine tools with respect to different worktable feed speeds[J].International Journal of Machine Tools and Manufacture,2013,72:73-84.
[15]范利洪.数控机床时变结构的动力学特性研究[D].武汉:华中科技大学,2013.FAN Lihong.Study on the dynamics of CNC machine tools time-variant structure[D].Wuhan:Huazhong University of Science and Technology,2013.
[16]LI Tianjian,DING Xiaohong,CHENG Kai,et al.Dynamic optimization method with applications for machine tools based on approximation model[J].Proceedings of the Institution of Mechanical Engineers,Part C:Journal of Mechanical Engineering Science,2017,232(11):2009-2022.
[2]李天箭,丁晓红,程凯.基于空间统计学的机床动力学特性[J].机械工程学报,2015,51(21):87-94.LI Tianjian,DING Xiaohong,CHENG Kai.Machine tool dynamics based on spatial statistics[J].Journal of Mechanical Engineering,2015,51(21):87-94.
[3]王信锐.数控机床能量模型及其应用研究[D].大连:大连理工大学,2013.WANG Xinrui.Energy model of CNC machine tool and its application research[D].Dalian:Dalian University of Technology,2013.
[4]郭垒,张辉,叶佩青,等.基于灵敏度分析的机床轻量化设计[J].清华大学学报,2011,51(6):846-850.GUO Lei,ZHANG Hui,YE Peiqing,et al.Lightweight design of machine tools based on sensitivity analysis[J].Journal of Tsinghua University,2011,51(6):846-850.
[5]DING Ye,ZHU Limin,ZHANG Xiaojian,et al.Response sensitivity analysis of the dynamic milling process based on the numerical integration method[J].Chinese Journal of Mechanical Engineering,2012,25(5):940-946.
[6]ZHAO Liping,CHEN Hongren,YAO Yiyong,et al.Anew approach to improving the machining precision based on dynamic sensitivity analysis[J].International Journal of Machine Tools and Manufacture,2016,102:9-21.
[7]廖伯瑜.现代机械动力学及其工程应用[M].北京:机械工业出版社,2003.LIAO Boyu.Modern mechanical dynamics and application[M].Beijing:China Machine Press,2003.
[8]LAW M,ALTINTAS Y,PHANI S.Rapid evaluation and optimization of machine tools with position-dependent stability[J].International Journal of Machine Tools and Manufacture,2013,68:81-90.
[9]邓聪颖,殷国富,方辉,等.基于正交试验的机床结合部动刚度优化配置[J].机械工程学报,2015,51(19):146-153.DENG Congying,YIN Guofu,FANG Hui,et al.Optimal configuration of dynamic stiffness of machine tool joints based on orthogonal experiment[J].Journal of Mechanical Engineering,2015,51(19):146-153.
[10]MAO Xinyong,LUO Bo,LI Bin,et al.An approach for measuring the FRF of machine tool structure without knowing any input force[J].International Journal of Machine Tools and Manufacture,2014,86:62-67.
[11]刘鲁宁.高速面铣刀模态参数及其对切削性能影响研究[D].济南:山东大学,2013.LIU Luning.Research on modal parameters and its influence on cutting performance of high speed milling cutter[D].Jinan:Shandong University,2013.
[12]ZAGHBANI I,SONGMENE V.Estimation of machine-tool dynamic parameters during machining operation through operational modal analysis[J].International Journal of Machine Tools and Manufacture,2009,49(12-13):947-957.
[13]张兴朝.基于有限元分析的模块化数控机床结构动态设计研究[D].天津:天津大学,2001.ZHANG Xingchao.Dynamic design of modular CNCmachine tools based on finite element analysis[D].Tianjin:Tianjin University,2001.
[14]LI Bin,LUO Bo,MAO Xinyong,et al.A new approach to identifying the dynamic behavior of CNC machine tools with respect to different worktable feed speeds[J].International Journal of Machine Tools and Manufacture,2013,72:73-84.
[15]范利洪.数控机床时变结构的动力学特性研究[D].武汉:华中科技大学,2013.FAN Lihong.Study on the dynamics of CNC machine tools time-variant structure[D].Wuhan:Huazhong University of Science and Technology,2013.
[16]LI Tianjian,DING Xiaohong,CHENG Kai,et al.Dynamic optimization method with applications for machine tools based on approximation model[J].Proceedings of the Institution of Mechanical Engineers,Part C:Journal of Mechanical Engineering Science,2017,232(11):2009-2022.