Experimental Design And Optimization Of The Ultra-precision Nanometer Time-grating Sensor System

Nanometer measurement technology has become a world popular research topicIndustrially developed countries including the United States, Germany and Japan attachgreat importance to nanometer measurement technology as an important part of nationalnanotechnology strategy. Under these circumstances, nanometer time-gratingdisplacement sensor was put forward, which is a kind of capacitive displacement sensorbased on area-changing electric field coupling principle. This sensor takes the advantageof the fact that currently the time measurement has three orders of magnitude moreaccuracy than spatial measurement, uses high-frequency clock pulse interpolationtechnology and obtains spatial displacement at nanometer level through thehigh-precision measurement of time difference. Combined with electric field couplingtheory, sensor has made great breakthrough in the field of signal acquisition, stable andhigh strength of the signal can be achieved； The introduction of micro-nanomanufacturing technology makes the sensor more convenient and reliable inmanufacturing and processing, and the design of differential plate condenser principlemakes the sensor simpler and easier to install. All the advantages the nanometertime-grating displacement sensor solve the crux of the original time-grating displacementsensor, therefore, it is necessary to research on nanometer time-grating displacementsensor. Theoretically speaking, nanometer time-grating displacement sensor is expectedto reach nano-scale measurement precision or even higher precision. However, sincethere is no mature technology and materials to learn, making such a research is aninnovative work, this is why the combination of a large number of experiments andtheories is needed for gradually forming a series of design theory of nanometertime-grating displacement sensor. In addition, it is necessary to design an ultrapreciseexperiment system for successful experiments of nanometer time-grating displacementsensor.This research focuses on designing and optimizing the ultraprecise experimentsystem of nanometer time-grating displacement sensor. To this purpose, some work hasbeen done as shown in the following: first, this research specifically elaborates thestructure and operating principle of nanometer time-grating displacement sensor, findsout the source of error in the nanometer time-grating experiment system by analyzing theexperiment system and builds up error theory model. Secondly, in accordance with the design requirement of ultraprecise experiment system, this research studies the movingmeasurement head drive system of nanometer time-grating displacement sensor. Bycomparing two sets of scheme design and experiment，this research finally choosesair-floating platform to guarantee the accurate movement of nanometer time-grating’smeasurement head. Thirdly, through designing and optimizing four plans of theinstallation of nanometer time-grating’s fixed measurement head, makes the experimentmore convenient, this research gets the effect law that sensor’s geometric machineryinstallation position brings to accuracy. Fourthly, by combining LabVIEW software in thedevelopment platform of virtual instrument with the hardware, namely the arbitrarywaveform generator PXI-5422produced by NI company, this research designs ahigh-precision experiment signal incentive system of nanometer time-grating sensor,which facilitates the research of sensor signal system. Finally, by designing andoptimizing the ultraprecise experiment system, this research carries out a large quantity ofexperimental test and analysis, which gets the conclusion that the accuracy of nanometertime-grating displacement sensor in experiments can reach±400nm with the traveldistance within200mm.