Research On Integrated Quartz Resonant Accelerometer And Temperature Compensatio

Quartz resonators have force-frequency characteristics under the action of stress,and can be used as sensitive components of accelerometers,and are widely used in national defense,industry and civil fields.However,due to the temperature-frequency characteristics of the quartz crystal itself and the stress caused by the thermal expansion effect of the conversion structure,when the temperature changes,the frequency of the quartz resonator will change,resulting in an accelerometer with a quartz resonator as a sensitive element(referred to as quartz accelerometer)output drifts.In this paper,in order to further improve the force-frequency characteristics of quartz resonators and suppress the influence of temperature on quartz accelerometers,this paper uses a new multi-electrode integrated quartz resonator cluster as a sensitive element to form a quartz accelerometer,and at the same time combines software and hardware.Perform temperature compensation to improve the accelerometer’s resistance to temperature interference.1.According to the energy trap theorem of crystal vibration,the finite element method is used to analyze the three-dimensional vibration mode of the resonator cluster.Six pairs of gold electrodes with a diameter of 1.5 mm and a thickness of 135 nm were sputtered on a circle with a center and a radius of 3.8 mm to form six quartz resonators with a fundamental frequency of 20 MHz.At the same time,the stress distribution of the quartz resonator in the accelerometer support structure and the influence of the thermal stress of the support structure on the resonator frequency under the action of temperature are simulated and analyzed.2.the resonant circuit,the difference frequency circuit and the FPGA frequency measurement system are designed,and the acquisition and processing of the frequency signal of the accelerometer are completed.At the same time,DS18B20 is selected as the temperature acquisition chip to obtain the ambient temperature of the integrated quartz resonant accelerometer,and the upper computer measurement and control program of the accelerometer is designed based on the.NET development platform to realize the reading and display of various values of the accelerometer.3.The prototype of the integrated quartz resonant accelerometer is designed,and the performance test of the accelerometer is completed with the help of the tilt turntable and the centrifuge.The experimental results show that under±10g,the scale coefficient of the accelerometer is 3542.5Hz/g,and the linear correlation coefficient is R~2=0.99998.4.In the high and low temperature experimental box,the static output characteristics of the accelerometer prototype and sensitive components in the temperature range of-20℃to80℃were tested.Combined with the temperature-frequency characteristics of the quartz resonator and the thermal stress of the accelerometer support structure,the resonator resonates For the influence of frequency,on the basis of using hardware difference frequency processing to realize temperature compensation,the radial basis(RBF)neural network model is used to perform temperature compensation on the output of the accelerometer,which improves the stability and resistance to temperature interference of the accelerometer.ability.It provides a basis for the design and optimization of an integrated high-precision quartz resonant accelerometer.