Design Of Closed-Loop Detection System For Silicon-Based Ring Gyroscope

In recent years,the ring gyroscope has gradually become a hot research topic in various countries.Because of its axisymmetric structure,it has the advantages of high energy transfer efficiency and good impact resistance.The silicon micro-ring gyroscope is an axially symmetric gyroscope based on MEMS technology,so it also has the characteristics of small size,low production cost and mass production.At present,the micro inertial navigation system based on the silicon-based ring wave gyroscope has been widely used in China.However,due to the highly symmetrical structure of the silicon-based ring gyroscope,the modal frequency difference of the gyroscope is low,and the low gyroscope bandwidth is mainly determined by the modal frequency difference,so the dynamic performance of the gyroscope is poor and the scale factor is low.There are some imperfect factors in the detection mode of the gyroscope,such as noise,nonlinear response and temperature change.These factors will affect the accuracy of the detection mode and have a negative impact on the performance of the gyro system.Therefore,it is an important means to improve the performance of the gyroscope by designing a detection closed-loop control system to eliminate the detection mode displacement of the ring gyroscope and improve the detection mode bandwidth of the gyroscope.In this paper,by studying the double U-shaped silicon-based ring wave gyroscope independently designed by the research group,the detailed theoretical derivation and system test of the detection mode of the silicon-based ring wave gyroscope are carried out.Finally,the detection mode control system of the gyroscope is designed.The main work is as follows :Aiming at the problem of poor dynamic performance of silicon-based ring wave gyroscope,this paper proposes a series phase correction detection closed-loop system controller based on Proportion Integral Differential-Inertial Element(PID-IE).Based on the structural motion equation of silicon micromachined gyroscope,an ideal system model of narrow frequency difference U-shaped elastic beam silicon-based ring wave gyroscope is established.Through the analysis of the transfer function and baud diagram of the system model and its peripheral circuit under the open-loop working state of the ring gyroscope,a detection closedloop system controller based on PID-IE is designed.Through the time domain simulation of the peripheral circuit of the ring gyroscope system,the effectiveness of the detection closed-loop control system is verified.Through simulation,it is found that the gyro output stabilization time is reduced by 50 % after adding the controller,and the gyro detection displacement output is reduced by 2 orders of magnitude.The detection displacement suppression of the gyroscope is basically realized.After realizing the detection closed-loop control system in the analog circuit,the performance indexes of the gyroscope before and after the detection closed-loop control are tested by experiments.Through experimental tests,it is found that after the closed-loop control is realized,the gyro output stabilization time is about 0.15 s,the gyro detection displacement is reduced by 97 % compared with the open-loop working state,the scale factor is increased from 0.74 mV / ° / s to 8.16 mV / ° / s,the bias and bias stability are increased by 3 times and 8 times respectively,and the detection mode working bandwidth is expanded from 3.9 Hz to 93 Hz.