Miniaturized Time-grating Angle Sensors Based On MEMS

The sensor is towards miniaturization and high precision with developing of microelectronics rapidly,a new type of miniaturized electric-field type circular time grating sensor is studied in this paper.The orthogonal change electric field is used to a motion reference,and the electric signal is induced by the electric field coupling directly.Compared with the traditional time grating,the intermediate link of the induction signal is reduced,so the anti-interference ability is stronger.Using MEMS micro-nanofabrication processing is used to ensure the accuracy of the sensor.As it is a new type of capacitive displacement sensor,which has the advantages of a simple structure,low power consumption,simple signal acquisition and processing for the sensor miniaturization and highly integrated.To improve the precision of measuring with the sensor is miniaturized,therefore,combined with theoretical analysis,model simulation and experimental verification,and gradually form a guiding significance theory of electric field type circular time grating sensor.Around the optimization of the structure of the electric field type circular grating sensor.The following working carry out: 1.Introduce the theory of time-space coordinate transformation,the working principle of mechanical time grating and electromagnetic time grating.In this paper,the double row and single row structure of the electric field type circular grating sensor are further studied,and their working principle were introduced in detail.2.Based on COMSOL Multiphysics simulation software to established an electric field simulation model of double row structure of the sensor,the difference between the inner and outer two circles of the double row structure are clarified,and combined with theoretical analysis of this difference will produce secondary error.A single row type structure simulation analysis of the sensor will eliminate the differentia.Relying on the simulation results,the size and the number of poles of the miniaturized sensor are determined and manufactured.3.According to the experimental requirements,build the experimental platform,the optimization of the double row structure of the sensor is experimentally verified,combined theoretical analysis with simulation results was carried out by means of a large number of experiments.Find the source of error and optimize the structure.Analyzed unequal amplitude of two standing waves,installation tilt,pole piece manufacturing error will produce secondary errors;the amplitude of the excitation signal is unequal,and the two phase standing waves are not strictly orthogonal will produce firstand secondary errors,third harmonic and quintuple harmonics of the sensor will bring biquadratic error.The experimental result shows that the final precision of circular time grating sensor with a diameter of 57 mm reaches ±2.5 " and the resolution is enhanced to 0.18".