Design And Application Of The Microforce Sensor Calibration System Based On Electrostatic Force

The measurement of static and dynamic microforce is widely used in biomedicine,materials,MEMS and other fields,to guarantee its accuracy and precision,the calibration of microforce sensor shows very important.This paper analyzes the research results at home and abroad,introduces the relevant theories,and establishes the measurement system of the static force value and dynamic force value measurement of uN class.The experiment device for the calibration of the static microforce value sensor and the dynamic microforce value sensor are built respectively,and the interface control program of the upper computer is completed.Finally,the calibrated sensor is applied to experiment,which proved the feasibility of the measurement scheme and device.The main research work of this paper is as follows:1.A in-depth comparative study at home and abroad of micro-nano force measurement and traceability devices conducted,especially analysised small dynamic force value metering device,preliminary confirmed the experiment scheme of small dynamic force value sensor calibration in this topic.2.The simulation study of elastic sensor in Comsol Multiphysics was realized,the stiffness and mode of the elastic sensor were simulated,and the performance of various elastic elements designed by the laboratory was compared.3.Completed the equipment construction to calibrate cantilever beam stiffness.The device hardware and man-machine interactive interface was introduced,which was the base of the value transmit.4.Complete uncertainty analysis of microcantilever beam stiffness calibration,the factors of the ground vibration and air turbulence,laser interferometer displacement error,nanometer micro displacement error,hinge stiffness and cantilever beam itself manufacture error,et,which may affect the result of the experiment were analyzed,finally the relative uncertainty of the microcantilever beam stiffness calibration was less than 5%,meet the goals and objectives.5.Small dynamic force sensor selection was completed,ultimately determined PVDF piezoelectric film as the dynamic force sensor,parts of PVDF piezoelectric film signal collection circuit was introduced,including the electric charge amplifier circuit,high and low pass filter circuit and the voltage amplification circuit.6.Completed the equipment construction to calibrate dynamic force sensor.The device hardware and man-machine interactive interface was introduced,PVDF piezoelectric film stiffness can be calibrated,the relative uncertainty was less than 4%,meanwhile,completed the repetitive experiment,The standard deviation was 0.64,repeatability was good.7.Based on PVDF piezoelectric thin film,the experiment of water strider disengagement force measurement was designed.Water strider's legs are extremely hydrophobic because of the presence of fine bristles.Introduced the theory of super hydrophobic,water strider disengagement force measurement was realized by using calibrated PVDF piezoelectric film,which get the force is 0.313 uN,the force value level consistented with theoretical analysis,proved the feasibility of the experiment.