Precision Angular Displacement Measurement Method And Experimental Study Based On Alternating Electric Field

Precision metrologicalmeasurement is one of the three main techniques of modern manufacturing,which is the core of high-tech manufacturing.In the field of angular displacement, the main problem of small scale of optical measurement is how to overcome the diffraction limit.While the main problem of large scale measurement is how to improve the measurementaccuracy and perform error tracing.Based onthe previous studies of time grating,The excitation voltages are used to generate orthogonal change electric field as a motion reference.In this way,a new method of precision angular displacement measurementis realized. "Electrode surface" is used as sensing unit to pick up the signal. Such method reduces the manufacturing difficulty;Using the average effect of "Electrode surface" array reduces the influence of the manufacturing accuracy;In addition, Using high frequency clock as displacement measurement reference solve the resolution problem of "Electrode surface".The electric field type circle time grating sensoris a new principle of displacement sensor.A large number of simulation and experimental verification are carried out based on the theoretical research. And a set of precision angular displacement measurement system is gradually developed. The maincontentsare as follow: 1.Further studyingthe time-space transformation theory and the basic measurement principles of time grating, and presenting a new structure of the electric field type circle time grating sensor, and mainly focusing on the theoretical derivationof the measurement model of sensor.2. According to the characteristics of sensor,the electric field simulation model is established based on the ANSYS Maxwell electromagnetic field simulation software. The parameters of fixed ruler andmoving ruler, such as electrodes, wires, the electric field distribution between sensor electrodes, are mainly researched. In addition, some simulations of influences on the electric field distribution caused by some factors, such as shielding layer, intervals between the electrodes, gap between the fixed ruler and fixed ruler and the excitation voltages, are performed. 3. The experimental platform is established and some experiments are performed combining with the simulation analysis. Some factorslimiting the measuring accuracy are found, and the corresponding solutions are proposed. The purpose is to constantly optimize the sensor structure.The electric field type circle time grating sensor concentrates on theory research, the electric field simulation analysis and experimental research.Measurement theory is sophisticated and system design is optimized in thebasis of theory with practice. Experiment results shown that themeasurement precision of the sensor is±2 " in 0°~ 360°,and resolution is 0.1".