Two-dimensional Nano Time-grating Displacement Measurement Method And Research Based On Plane Alternating Electric Field

The precision of displacement measurement technology determines the upper limit of a country's industrial development.In addition to traditional linear displacement sensing and angular displacement sensing,precise two-dimensional displacement measurement is an important feedback for plane motion and can be applied to various plane positioning.Demanding occasions,such as PCB and chip manufacturing,so the demand for two-dimensional displacement sensors in today's industrial development is becoming more and more extensive,and higher requirements are also put forward for two-dimensional displacement sensors.At present,two-dimensional displacement sensors that have been widely used and developed more mature are grating two-dimensional displacement sensors and two-dimensional displacement sensors based on the principle of a magnetic field.For the two-dimensional displacement sensor based on the magnetic field,although the structure is simple,the installation is cumbersome and the accuracy is often not high.For the grating displacement sensor,no matter how to optimize the peripheral design,it always faces the problem of grating line scribing of the grating ruler,that is,the grid line.The precision and quality of the scribing determine the accuracy of the displacement measurement.The time-grating displacement sensing method came into being in such a large environment.It does not rely on precise scribe lines and is not easily affected by the external environment.In addition,the one-dimensional time-grating displacement sensor based on alternating electric field in the early stage has reached the stage of surface vector production,which is an ideal displacement sensor.As an original idea put forward by Chinese people,the principle of time-grating measurement is based on the theory of time-space transformation.After 30 years of unremitting efforts by the team,it has developed into a relatively mature sensing method.The one-dimensional linear displacement sensor based on the alternating electric field is the focus of the previous team's research.Now it has reached the stage of industrialization.Based on the previous research,the author creatively expands the one-dimensional displacement sensing method to two-dimensional displacement sensing method,then designs and manufactures the sensor prototype.Like the electric field linear time-grating sensor,after applying excitation on the fixed length,the induction signal can be collected on the moving scale,and then the induction signal can be processed by the subsequent circuit to obtain the displacement value.However,for two-dimensional displacement measurement,there are still two problems: First,in the design of electric field-type one-dimensional linear displacement sensor,the alternating electric field needs to be excited in one direction.In two-dimensional displacement measurement,how to realize it in two directions At the same time,the alternating electric field is excited without interfering with each other;the second is how to decouple the acquired induction signals to obtain independent displacement values in two directions.With the above problems,the two-dimensional time-grating displacement measurement method and research based on the plane alternating electric field are carried out.The main research contents are as follows:(1)Theoretical research: the domestic and foreign research status of the planar two-dimensional displacement sensor was investigated,and the relevant domestic and foreign documents were searched,and the grating two-dimensional displacement sensor was analyzed with emphasis on the difficulty of manufacturing the grating two-dimensional displacement sensor.In combination with the research foundation of the measurement principle,traveling wave signal generation method,and displacement signal processing method of the one-dimensional time-grating sensor based on the alternating electric field in the early stage,a discrete array planar two-dimensional time-grating sensor model is proposed.The theoretical mathematical derivation is also proposed,and a planar two-dimensional time-grating sensing signal decoupling method using linear combination operations between the moving ruler pole pieces is proposed.It is theoretically analyzed how to realize independent displacement measurement in two directions through the combined operation of moving ruler pole pieces.(2)Model simulation: The COMSOL finite element analysis software was used for simulation analysis,and the three-dimensional electric field simulation model of the two-dimensional time-grating based on the plane alternating electric field was established.When the ruler pole piece moves,the induced signal on the moving ruler pole piece changes.The decoupling method is used to verify the feasibility of the decoupling method.The decoupling traveling wave signal is fitted and the theoretical error is calculated and analyzed.The error characteristics and error laws are described.(3)Experimental verification: Based on theoretical derivation and simulation analysis,the sensor prototype was manufactured and the experiment was conducted to verify the feasibility of the measurement method and decoupling method of the planar two-dimensional time-grating sensor model,and the sensor structure was optimized according to the experimental results The experiment was carried out again,and the experimental results showed that after optimization,the error of the planar two-dimensional time-grating sensor was further reduced,and finally within the effective measurement range of 200mm×200mm,the error in the X direction reached ±8?m,and the error in the Y direction reached ±8.4 ?m.