With ongoing economic,scientific,and technological developments,the electronic devices used in daily lives are developing toward precision and miniaturization,and so the demand for high-precision manufacturing machine...With ongoing economic,scientific,and technological developments,the electronic devices used in daily lives are developing toward precision and miniaturization,and so the demand for high-precision manufacturing machinery is expanding.The most important piece of equipment in modern high-precision manufacturing is the macro-micro motion platform(M3P),which offers high speed,precision,and efficiency and has macro-micro motion coupling characteristics due to its mechanical design and composition of its driving components.Therefore,the design of the control system is crucial for the overall precision of the platform;conventional proportional–integral–derivative control cannot meet the system requirements,and so M3Ps are the subject of a growing range of modern control strategies.This paper begins by describing the development history of M3Ps,followed by their platform structure and motion control system components,and then in-depth assessments of the macro,micro,and macro-micro control systems.In addition to examining the advantages and disadvantages of current macro-micro motion control,recent technological breakthroughs are noted.Finally,based on existing problems,future directions for M3P control systems are given,and the present conclusions offer guidelines for future work on M3Ps.展开更多
The null space of the 6-DOF gain decoupling matrix of actuators and a modified velocity feedback controller are adopted to suppress the vibration of the wafer stage during exposure.To deal with varying flexibilities a...The null space of the 6-DOF gain decoupling matrix of actuators and a modified velocity feedback controller are adopted to suppress the vibration of the wafer stage during exposure.To deal with varying flexibilities at different performance locations,the vibration controller is designed to be a time-variant linear quadratic regulator,using the conventional gain scheduling method,which could provide good vibration control for each field under exposure.This control method can guarantee the stability of the closed-loop system and will not deteriorate the rigid modes control of the wafer stage.To minimize the control spillover caused by the higher uncontrolled modes,actuator placement is optimized to minimize their controllability grammians in modal coordinates.An unconstrained rectangular plate is used to represent the fine stage of the wafer stage.Effectiveness of the proposed method is verified on the plate through a closed-loop simulation.展开更多
In order to optimize the transitional time during the successive exposure scans for a step-and-scanlithography and improve the productivity in a wafer production process,an investigation of the motion tra-jectory plan...In order to optimize the transitional time during the successive exposure scans for a step-and-scanlithography and improve the productivity in a wafer production process,an investigation of the motion tra-jectory planning along the scanning direction for wafer stage was carried out.The motions of wafer stagewere divided into two respective logical moves(i.e.step-move and scan-move)and the multi-motion-overlap algorithms(MMOA)were presented for optimizing the transitional time between the successive ex-posure scans.The conventional motion planning method,the Hazehon method and the MMOA were ana-lyzed theoretically and simulated using MATLAB under four different exposure field sizes.The resultsshow that the total time between two successive scans consumed by MMOA is reduced by 4.82%,2.62%,3.06% and 3.96%,compared with those of the conventional motion planning method;and re-duced by 2.58%,0.76%,1.63% and 2.92%,compared with those of the Hazelton method respec-tively.The theoretical analyses and simulation results illuminate that the MMOA can effectively minimizethe transitional step time between successive exposure scans and therefore increase the wafer fabricatingproductivity.展开更多
The automatic positioning control of mooring system for deepwater semi-submersible platform has become a key issue in the research and development field of deep-sea resources. The Dual- Stage Actuator (DSA) proposed i...The automatic positioning control of mooring system for deepwater semi-submersible platform has become a key issue in the research and development field of deep-sea resources. The Dual- Stage Actuator (DSA) proposed in this paper can replace the single actuator to achieve the high speed and high precision positioning by cooperative control. The relative model and control algorithm of motion trajectory (CAMT) are designed and validated, which proves that the method proposed in this paper is effective.展开更多
基金This research was supported financially by the China Postdoctoral Science Foundation,the National Natural Science Foundation of China(Grant No.51705132)the Young Backbone Teacher Training Program in Henan University of Technology,the Education Department of Henan Province Natural Science Project(Grant No.21A460006)the Natural Science Project of Henan Provincial Department of Science and Technology(Grant No.222102220088).
文摘With ongoing economic,scientific,and technological developments,the electronic devices used in daily lives are developing toward precision and miniaturization,and so the demand for high-precision manufacturing machinery is expanding.The most important piece of equipment in modern high-precision manufacturing is the macro-micro motion platform(M3P),which offers high speed,precision,and efficiency and has macro-micro motion coupling characteristics due to its mechanical design and composition of its driving components.Therefore,the design of the control system is crucial for the overall precision of the platform;conventional proportional–integral–derivative control cannot meet the system requirements,and so M3Ps are the subject of a growing range of modern control strategies.This paper begins by describing the development history of M3Ps,followed by their platform structure and motion control system components,and then in-depth assessments of the macro,micro,and macro-micro control systems.In addition to examining the advantages and disadvantages of current macro-micro motion control,recent technological breakthroughs are noted.Finally,based on existing problems,future directions for M3P control systems are given,and the present conclusions offer guidelines for future work on M3Ps.
基金Supported by the National Natural Science Foundation of China(51677104,51475262)。
文摘The null space of the 6-DOF gain decoupling matrix of actuators and a modified velocity feedback controller are adopted to suppress the vibration of the wafer stage during exposure.To deal with varying flexibilities at different performance locations,the vibration controller is designed to be a time-variant linear quadratic regulator,using the conventional gain scheduling method,which could provide good vibration control for each field under exposure.This control method can guarantee the stability of the closed-loop system and will not deteriorate the rigid modes control of the wafer stage.To minimize the control spillover caused by the higher uncontrolled modes,actuator placement is optimized to minimize their controllability grammians in modal coordinates.An unconstrained rectangular plate is used to represent the fine stage of the wafer stage.Effectiveness of the proposed method is verified on the plate through a closed-loop simulation.
基金the National Basic Research Program of China(No.2003CB716206)the National Natural Science Foundation of China(No.50605025)
文摘In order to optimize the transitional time during the successive exposure scans for a step-and-scanlithography and improve the productivity in a wafer production process,an investigation of the motion tra-jectory planning along the scanning direction for wafer stage was carried out.The motions of wafer stagewere divided into two respective logical moves(i.e.step-move and scan-move)and the multi-motion-overlap algorithms(MMOA)were presented for optimizing the transitional time between the successive ex-posure scans.The conventional motion planning method,the Hazehon method and the MMOA were ana-lyzed theoretically and simulated using MATLAB under four different exposure field sizes.The resultsshow that the total time between two successive scans consumed by MMOA is reduced by 4.82%,2.62%,3.06% and 3.96%,compared with those of the conventional motion planning method;and re-duced by 2.58%,0.76%,1.63% and 2.92%,compared with those of the Hazelton method respec-tively.The theoretical analyses and simulation results illuminate that the MMOA can effectively minimizethe transitional step time between successive exposure scans and therefore increase the wafer fabricatingproductivity.
文摘The automatic positioning control of mooring system for deepwater semi-submersible platform has become a key issue in the research and development field of deep-sea resources. The Dual- Stage Actuator (DSA) proposed in this paper can replace the single actuator to achieve the high speed and high precision positioning by cooperative control. The relative model and control algorithm of motion trajectory (CAMT) are designed and validated, which proves that the method proposed in this paper is effective.
文摘目的 探讨体素内不相干运动(intravoxel incoherent motion, IVIM)扩散加权成像定量参数及联合参数在治疗前诊断宫颈癌以及评估宫颈癌不同临床分期的价值。材料与方法 回顾性分析36例病理确诊的宫颈鳞癌患者病例及18例健康受试者资料,所有受试者均扫描MRI IVIM序列并获得以下参数:纯扩散系数(pure apparent diffusion coefficient, D)、伪扩散系数(pseudo-apparent diffusion coefficient, D*)、灌注分数(perfusion fraction, f)。所有患者根据国际妇产科医学联合会(Federation of International of Gynecologists and Obstetricians, FIGO)分期分为Ⅰ~Ⅳ期;<ⅡB期为早期宫颈癌,≥ⅡB期为中晚期宫颈癌。所有数据分析应用统计学软件SPSS 17.0进行。结果 D、D*、f值在宫颈癌组中要显著低于正常宫颈组(P<0.001);f值在Ⅰ、Ⅱ期与Ⅲ、Ⅳ期宫颈癌之间,以及早期(<ⅡB)与中晚期(≥ⅡB)宫颈癌之间差异有统计学意义(P<0.05)。联合参数D+f、D+f+D*对宫颈癌的识别效能最佳,曲线下面积(area under the curve, AUC)均为0.992;D、D+D*、D+f对早期宫颈癌识别效能最佳,AUC均为0.988。结论 IVIM定量参数可在治疗前鉴别宫颈癌和正常宫颈,有较好的诊断效能,联合各参数共同识别宫颈癌、早期宫颈癌诊断效能更佳;f值在宫颈癌的分期中有一定的价值。
