Research On The Cross-Scale Positioning Stage Based On The Driving Principle Of Dual Piezoceramics

With the rapid development of nanoscience and technology,the research direction of researchers tends to be more and more small fields,such as nanomaterials.In order to study the properties of materials in the micro and measure their mechanical and electrical properties,the development of micro-nano operating system has been paid more and more attention by the academic community,which achieved remarkable research results,such nanometer manipulator,nanometer material tester and atomic force microscope.This kind of micro-nano operating system often needs to operate and characterize nanomaterials with the help of the visual servo feedback function of scanning electron microscope(Scanning Electron Microscope,SEM),which poses a new challenge to the volume and positioning accuracy of micro-nano operating system.Under this background,this paper proposes a design scheme of a new cross scale precise positioning stage and studies the key technologies.This subject based on the research status of the micro nano operating system and the development trend of the nano positioning stage designed by the cross scale stick-slip drive precision positioning device at home and abroad,a dual piezoelectric ceramic drive cross scale nano positioning method is proposed to solve the problems of the micro nano operating system developed by this stage.And the mathematical equation and physical model of the positioning stage are established by combining the theoretical knowledge of tribology,and a new type of cross-scale precision positioning stage is finally developed.In this paper,the motion principle,dynamic model,structure and drive power supply design and verification experiment of the dual-pie ceramic drive system are studied in depth.(1)Research on the principle of dual piezoceramics drive.Through the description of the principle of sticky slip drive,the limitations of the sticky slip drive positioning stage are analyzed,and the principle of dual piezoceramic drive is proposed for the problems of nano-operating system based on the sticky-slip drive positioning stage.Based on the description of the sticky slip drive principle,the motion characteristics of the dual piezoelectric ceramic drive principle are analyzed.The static friction model and dynamic friction model were compared and analyzed.Finally,Lugre friction model was used to describe the friction between guide rail and flexible drive parts.(2)The establishment and analysis of the dynamic model of the positioning stage.In order to further analyze the effect of the motion law and dynamic parameters of the positioning stage on its motion performance,the theoretical model of the positioning stage is simulated.Firstly,the mathematical model of electromechanical transformation of piezoelectric ceramics is established by establishing the electrical equilibrium equation and the mechanical equilibrium equation.Secondly,the piezoelectric ceramic actuator and the flexible actuator are regarded as a driving system with a moving unit as the positioning stage,and the dynamic modeling of the system is carried out.Finally,the Lugre friction model was applied to the dynamics model of the drive system,and the overall dynamics model of the positioning stage was constructed.Simulink dynamics simulation module in Matlab software was used to analyze the dynamics model.(3)System design of the positioning stage.The design scheme of the flexible drive parts is driven in series and split-time of large piezoelectric ceramics and small piezoelectric ceramics,and the initial structure of the flexible transmission is drawn using Solidworks 3D drawing software.Firstly,the deformation characteristics of the flexure hinge in the process of motion are analyzed and then the ideal stiffness range of the flexure hinge is calculated by combining the relation curve between the output force and the output displacement of the piezoelectric ceramic actuator.Secondly,the finite element simulation software ANSYS Workbench is used to analyze the stiffness of the flexure hinge,check the strength of the flexible drive parts and calculate the resonance frequency.Thirdly,the piezoelectric ceramic driving power supply is designed according to the requirements of the voltage driving signal of the positioning stage.Finally,the overall structure of the positioning stage is designed and the prototype is developed.(4)Experimental research on positioning stages.The test system is constructed according to the test content of the motion performance of the dual-pie ceramic drive positioning stage.From the perspective of motion mode,the motion performance test of the positioning stage is divided into the performance test of small piezoceramic step mode and the performance test of large piezoelectric ceramic scanning mode,and the experimental content mainly includes the resolution,minimum step length,maximum motion speed,load capacity and dynamic parameters influence the motion performance of the positioning stage.By comparing the experimental results with the theoretical data obtained from the dynamic simulation,the rationality of the positioning stage structure is verified.