扫描隧道显微镜扫描器的迟滞非线性控制  

Control of Hysteresis Nonlinearity for Scanning Stage in Scanning Tunneling Microscope

作　　者：季宏丽[1] 孙宏君[1] 裘进浩[1] 陈远晟[2] 朱孔军[1] 

机构地区：[1]南京航空航天大学机械结构力学及控制国家重点实验室,南京210016 [2]南京理工大学能源与动力工程学院,南京210094

出　　处：《振动．测试与诊断》2017年第2期221-227,共7页Journal of Vibration,Measurement & Diagnosis

基　　金：国家重点基础研究发展计划("九七三"计划)资助项目(2015CB057501);国家自然科学基金资助项目(11372133&51405235);中央高校基本科研业务费专项资金资助项目(NE2015001&NE2015101);中国博士后特别资助项目(2014T70514);江苏省基金重点资助项目(BK20150061);江苏高校优势学科建设工程资助项目

摘　　要：压电驱动器被广泛应用于扫描隧道显微镜(scanning tunneling microscope,简称STM)的扫描器,但压电材料本身的迟滞非线性特性影响了STM的扫描精度。为了补偿由于迟滞非线性带来的扫描器控制误差,提高STM的扫描精度,基于迟滞非线性模型,设计了前馈控制器,并与PID反馈控制相结合。利用所设计的控制器进行了扫描实验,并与位移反馈控制扫描进行对比。实验结果表明,采用位移反馈控制时光栅周期相对测量误差和光栅线宽相对测量误差分别为4.41%和2.65%,采用迟滞逆模型与PID反馈的复合控制后,光栅周期相对测量误差和光栅线宽相对测量误差分别减小到1.26%和0.27%,迟滞引起的非线性误差得到了补偿,减小了扫描器控制误差,提高了扫描精度。Piezoelectric actuators have been widely applied in scanning tunneling microscope (STM). A controller combining inverse hysteresis model and PID control law was designed for the STM to compensate for the hysteresis nonlinearity of piezoelectric actuators and to improve the scanning accuracy. For the purpose of comparing the proposed controller with classical displacement feedback control law, experimental system was built in this investigation. The relative measuring error of grating period and width of grating line were 4.41% and 2.65% using the classic displacement feedback control method respectively. And they were reduced to 1.26% and 0.27% in proposed method. Experimental results indicate that the error caused by hysteresis nonlinearity has been well compensated, and the scanning accuracy is improved with the help of such controller. © 2017, Editorial Department of JVMD. All right reserved.

关 键 词：扫描隧道显微镜 压电驱动器 迟滞控制 扫描控制 

分 类 号：TP271[自动化与计算机技术—检测技术与自动化装置] TH702[自动化与计算机技术—控制科学与工程]