工作台微定位特性分析及误差补偿研究
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摘要
随着表面形貌测量、超精密加工及生物医学工程等众多领域的不断发展,与之相关的设备对定位行程、定位精度的要求越来越高,因此大行程高精度的定位技术在现代科学技术中起到十分关键的作用,近年来一直是精密工程领域的研究热点之一。
论文以宏微双重驱动方式大行程高精度定位系统中的宏动台为研究对象,研究了以交流伺服电机加滚珠丝杠传动,光栅测量为反馈系统的宏动台的运动特性与定位误差,研究内容包括:
1通过物理样机实验,指定工作台运动行程为2mm,选择有代表性的低速0.006mm/s、中速0.27mm/s、高速25mm/s运动,采样光栅测量到莫尔条纹计数值,分析低速爬行、滞后性、高速振荡三种非线性特性,得到结论宏动台在低速和高速情况下,定位特性差。
2基于ADAMS/View的宏动台机械系统建模与仿真,通过改变系统刚度、阻尼、工作台质量,从而确定传动件刚度大,阻尼大,工作台质量轻,工作台的运动线性度好,从而宏动台的定位性好。
3对定位系统中各种误差的来源,包括机械和光栅测量系统等误差进行了详细分析,并对误差进行静态误差与动态误差分类,为误差补偿提供依据。结合微定位实验数据与误差分析,基于MATLAB建立误差补偿模型,采用曲线拟合的数值分析方法,选择了多项式模型,并将该多项式数学函数表达式应用于软件补偿中,定位精度达到2um。
本文综合运用了建模与仿真、虚拟样机技术等知识,对光电检测实验室的宏微双重驱动精密工作台整体研究有重要意义。文中的研究对象是典型的机械传动系统,所涉及的建模仿真方法适用于其它机械传动系统的性能分析与设计,具有一定的理论意义和工程实用价值。
As the developing of surface topography measurement, extra-precise processing, biomedical engineering and a great number field, the positioning stroke and positioning accuracy require higher and higher to satisfy the related equipments. So the positioning technique which is wide stroke and high accuracy has a pivotal effect on modern science and technology. In recent years it is always one of the hot researching spot in the precision engineering field.
The researched object of paper is the macro-stage, which is in the macro-micro dual-drive large travel and high precision positioning system. The paper researches the kinetic characteristic and positioning error of the macro-stage, AC servo motor and ball screw and nut are used in the macro motion. The contents are as follows:
1 With the method of experiment, the paper samples Moiréfringe in the circumstances which the distance is 2mm and the speeds are 0.006mm/s, 0.27mm/s, 25mm/s and analyses stick-alip phenomenon, hysteresis quality and oscillation.The results indicate that positioning is bad in the circumstances with low speed and high speed.
2 Modeling and simulation of macro-stage based on ADAMS, changes stiffness, damping and mass. The results indicate that the positioning is very well with high stiffness, large damping and small mass.
3 The paper analyses the error source, including mechanical part and measurement system, and error trait. The analysis has a pivotal effect on error compensate. Modeling the error compensate based on MATLAB with the data of kinetic characteristic experiments and error traits, the paper can get the mathematical expression of error compensate modeling by fitting curve. The positioning accuracy is 2um.
The paper comprehensively applies system modeling, emulation, virtual prototype and other knowledge. It is very important that research the macro-micro dual drive precision stage in photo electricity detecting laboratory. At the same time, the object is a typical mechanical drive system, the modeling and simulation method is suitable for other mechanical drive system to analyze and design, which has a certain theory significance and practical value.
论文以宏微双重驱动方式大行程高精度定位系统中的宏动台为研究对象,研究了以交流伺服电机加滚珠丝杠传动,光栅测量为反馈系统的宏动台的运动特性与定位误差,研究内容包括:
1通过物理样机实验,指定工作台运动行程为2mm,选择有代表性的低速0.006mm/s、中速0.27mm/s、高速25mm/s运动,采样光栅测量到莫尔条纹计数值,分析低速爬行、滞后性、高速振荡三种非线性特性,得到结论宏动台在低速和高速情况下,定位特性差。
2基于ADAMS/View的宏动台机械系统建模与仿真,通过改变系统刚度、阻尼、工作台质量,从而确定传动件刚度大,阻尼大,工作台质量轻,工作台的运动线性度好,从而宏动台的定位性好。
3对定位系统中各种误差的来源,包括机械和光栅测量系统等误差进行了详细分析,并对误差进行静态误差与动态误差分类,为误差补偿提供依据。结合微定位实验数据与误差分析,基于MATLAB建立误差补偿模型,采用曲线拟合的数值分析方法,选择了多项式模型,并将该多项式数学函数表达式应用于软件补偿中,定位精度达到2um。
本文综合运用了建模与仿真、虚拟样机技术等知识,对光电检测实验室的宏微双重驱动精密工作台整体研究有重要意义。文中的研究对象是典型的机械传动系统,所涉及的建模仿真方法适用于其它机械传动系统的性能分析与设计,具有一定的理论意义和工程实用价值。
As the developing of surface topography measurement, extra-precise processing, biomedical engineering and a great number field, the positioning stroke and positioning accuracy require higher and higher to satisfy the related equipments. So the positioning technique which is wide stroke and high accuracy has a pivotal effect on modern science and technology. In recent years it is always one of the hot researching spot in the precision engineering field.
The researched object of paper is the macro-stage, which is in the macro-micro dual-drive large travel and high precision positioning system. The paper researches the kinetic characteristic and positioning error of the macro-stage, AC servo motor and ball screw and nut are used in the macro motion. The contents are as follows:
1 With the method of experiment, the paper samples Moiréfringe in the circumstances which the distance is 2mm and the speeds are 0.006mm/s, 0.27mm/s, 25mm/s and analyses stick-alip phenomenon, hysteresis quality and oscillation.The results indicate that positioning is bad in the circumstances with low speed and high speed.
2 Modeling and simulation of macro-stage based on ADAMS, changes stiffness, damping and mass. The results indicate that the positioning is very well with high stiffness, large damping and small mass.
3 The paper analyses the error source, including mechanical part and measurement system, and error trait. The analysis has a pivotal effect on error compensate. Modeling the error compensate based on MATLAB with the data of kinetic characteristic experiments and error traits, the paper can get the mathematical expression of error compensate modeling by fitting curve. The positioning accuracy is 2um.
The paper comprehensively applies system modeling, emulation, virtual prototype and other knowledge. It is very important that research the macro-micro dual drive precision stage in photo electricity detecting laboratory. At the same time, the object is a typical mechanical drive system, the modeling and simulation method is suitable for other mechanical drive system to analyze and design, which has a certain theory significance and practical value.
引文
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[2]米凤文,戴旭涵,沈亦兵,侯西云,杨国光.精密工作台定位控制系统的设计与研究[J].光学仪器,1998,20(5):18-22.
[3]王光亮,杨川.二维微动工作台的设计与分析[J].机床与液压,2008,36(5):1-4,8.
[4]孙艳玲,谢铁邦.一维计量型微位移工作台的研究[J].传感器世界,2006,12(3):17-20.
[5]节德刚,刘延杰,孙立宁,孙绍云,蔡鹤皋.一种宏微双重驱动精密定位机构的建模与控制[J].光学精密工程,2005(4):171-178.
[6] SANG JOOK, WANKC, YOUNGILY. On the coarse/fine dual-stage manipulators with perturbation compensator[C]. Proceedings of the 2001 IEEE International Conference on Robotics and Automation. Seoul, Korea. May, 2001:121-126.
[7] CANNON D W, MA GEEDP, BOOKWJ. Experimental study on micro/ macro manipulator vibration control[C].Proceedings of the 1996 IEEE International Conference on Robotics and Automation. Minneapolis, Minnesota. April, 1996:2549-2554.
[8] KWON S J,CHUN G W K. Robust and time-optimal control strategy for coarse/fine dual-stage manipulators[C].Proceedings of the 2000 IEEE International Conference on Robotics and Automation. San Francisco, CA. April, 2000:4051-4056.
[9]李鸣鸣.大行程纳米定位系统若干关键技术研究[D].上海:上海大学,2007.
[10]叶树亮,谭久彬.具有纳米分辨力二维超精密定位系统的研制[J].哈尔滨工业大学学报, 2005,(11):1472-1475.
[11]张海伟,李拢梅.X-Y数控平台伺服系统的建模与仿真[J].机械设计与制造,2008,7(7):68-69.
[12]龙泽明,李亚芹,李彩花.机床工作台滚珠丝杠高速驱动系统精密定位机械特性研究[J].组合机床与自动化加工技术,2006,(12):28-30.
[13]郑子文,李圣.滚珠丝杠传动机构的微动特性及轨迹分析[J].光学精密工程,2001,(8):360-362.
[14]卢礼华,郭永丰,下河边明,梁迎春.滚珠丝杠在超精密定位中的应用[J].航空精密制造技术,2007,43(1):21-23,16.
[15] Y. Arai, W. Gao, S. Kiyono, T. Kuriyagawa. Measurement of the Straightness of a Lead screw-Driven Precision Stage[J]. Key Engineering Materials Vols.295-296 (2005):259-264.
[16] S.K.Kim, D.W.CHo. Real-time estimation of temperature distribution in a ball-screw system[J]. International Journal of Machine Tools & Manufacture,1997,37(4):451-464.
[17] Heui Jae Pahk, Dong Sung Lee, Jong Ho Park. Ultra precision positioning system for servo motor-piezo actuator using the dual servo loop and digital filter implementation[J]. Machine Tools &Manufacture 41(2001):51-63.
[18]闫如胜,马修水,李桂华,应仲阳.光栅尺纳米测量技术研究及其发展[J].安徽电子信息职业技术学院学报,2008,7(34):70-71.
[19]王选择,郭军,谢铁邦.以正交衍射光栅为计量标准器的二维微位移工作台[J].光学精密工程,2003,11(5):492-496.
[20]王建林,胡小唐.纳米定位技术研究现状[J].机械设计与研究,2000,1:43-44.
[21]张晓峰,林彬.大行程纳米级分辨率超精密工作台的发展方向[N].南京航空航天大学学报,2005,11(37):179-183.
[22]朱煜,尹文生,段广洪.光刻机超精密工作台研究[J].光刻技术,2004,(109):25-27,44.
[23]罗兵,李艾利.超精密扭轮摩擦传动动力学研究[J].国防科技大学学报,1998,20(3):99-102.
[24] Chao C L, Neou J. Model reference adaptive control of air-lubricated capstan drive for precision positioning[J].Precision Engineering,2000,24(4):285-290.
[25] J.S.Chen, I.C.Dwang. A ball screw drive mechanism with piezo-electric nut for preload and motion control. Machine Tool & Manufacture,40(2000):513-526.
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