Dynamic Error Analysis And Structure Improvement Of Parasitic Time Grating Sensor

The uncertainty evaluation scheme of the parasitic time grating sensor has not been established the relationship between the sensor processing error,the installation error,the Doppler effect and the total uncertainty at present.Parasitic time grating has not established a high precision dynamic measurement error correction model.The structure of parasitic time grating is based on the experimental experience design,which lack of theoretical basis for guiding the structural optimization design.In order to establish a more comprehensive uncertainty evaluation system of the parasitic time grating,the transitive relation was established between the sensor processing error,the installation error,the Doppler effect and the total uncertainty based on the original uncertainty evaluation scheme of parasitic time grating.In order to establish a highly accurate dynamic measurement error model of parasitic time grating,the 84 poles of parasitic time grating was used as the research object and the dynamic error of the whole circumference of the parasitic type was collected in the design experiment.The corresponding relationship between the various components of the dynamic error and the source of error is analyzed.The Bayesian prediction model was chosen to build the whole circle dynamic error model of parasitic time grating sensor.The modeling method of cubic spline interpolation and BP neural network were also used to build the whole circle dynamic error model of parasitic time grating sensor and compared with the above Bayesian model.The modeling verification experiment results show that Bayesian prediction model based on standard value interpolation can get higher modeling accuracy in less time with less dataThe influence of installation error and Doppler effect on the measurement accuracy was analyzed by Ansoft Maxwell and the verification experiment was designed.The results of simulation and experiment show that the smaller the gap between the probe and the rotor,the higher the measurement accuracy of sensor and the best installation gap is 0.2mm.The influence of pitch angle and yaw angle of the probe on the measurement accuracy is complex,so the corresponding error compensation model is established.The influence of Doppler effect on the measurement accuracy of the sensor is greater with the increase of rotor speed.In order to correct the measurement error caused by installation error of parasitic time grating in real time,the structure of the eddy current sensor was coupled into the structure of parasitic time grating.Three-point error separation technique was used to measure the rotation angle of the measured object in real time,which could compensate the measurement error caused by the installation errors of parasitic time grating in real time.A self-compensating parasitic time-grating sensor was designed,and its mechanical structure and processing circuit were designed.Ansoft Maxwell was used to simulate the induction signal of the sensor.The existing uncertainty evaluation scheme of parasitic time grating is improved in this paper.A high accurate dynamic measurement error model of parasitic time grating is built.The influence of installation error and Doppler effect on the measurement accuracy is analyzed.In order to eliminate the influence of the installation error,A self-compensating parasitic time-grating sensor is designed.