Research On Acceleration Effect Correction Technology Of Piezoelectric Pressure Sensor

With the continuous development of modern technology,artillery still occupies a place on the battlefield.Measuring the change in the bottom pressure of the bomb during the firing process of the artillery is an important and difficult artillery interior ballistic test technique.Piezoelectric pressure sensors are widely used in the field of dynamic test systems due to their high sensitivity,high linearity and stability,wide measurement range,high frequency response,simple and convenient use,and ability to collect rapidly changing dynamic pressure without distortion.The bottom pressure signal of the artillery shell has the characteristics of high pressure,high impact,high speed and instantaneity.Therefore,the piezoelectric pressure sensor is also used in the bottom pressure measurement of the shell.The firing process of artillery projectiles usually has the characteristics of high impact and high pressure.Piezoelectric pressure sensors rely on piezoelectric crystals to measure pressure signals due to their internal structure.This also means that the inertial force brought by high acceleration will also be captured by the sensor.Part of it affects the measurement accuracy.Therefore,when the piezoelectric pressure sensor is used to measure the transient pressure of the bomb bottom,the acceleration effect of the piezoelectric pressure sensor and its correction technology must be studied.First of all,a simplified modeling of the piezoelectric pressure sensor used in the bomb bottom pressure test system designed in this paper is carried out.The simplified model is analyzed by finite element analysis through simulation software,and a series of pressure loads and acceleration loads are applied to verify the acceleration load Affect the output of the piezoelectric pressure sensor.Secondly,in view of the large amount of calculation in the traditional least squares identification method and the inaccurate calculation results,a "method that can simultaneously identify the order and parameters of the differential equation model of the system" is used in the identification of the acceleration effect system.The acceleration sensor BM1010 and the piezoelectric pressure sensor kislter6215 B are installed on the impact table for testing to obtain acceleration data and pressure sensor output data.Then,the output data is used to identify it systematically,and a seven-order model of acceleration effect is established.The verification results show that the model fits well.Finally,a modified model is built in SIMULINK and the model obtained from the identification is applied to the measured bottom pressure signal of the bomb.The results show that this modified model can reduce the impact of the acceleration effect in the bottom pressure of the bomb.In this paper,the overall system identification of the bomb bottom pressure tester is carried out,and the acceleration effect system model of the bomb bottom pressure tester is obtained.On this basis,the acceleration effect error in the bottom pressure test of the live bomb is corrected.