用于微振动测量的高精度加速度传感器标定方法

微振动试验中所用的加速度传感器简称高精度加速度传感器,其相比于常规加速度传感器测量量级很低,可以达到10-5g量级甚至更低,用常规的加速度动态标定技术无法实现该量级水平的标定,也无从验证其测量精度的准确性。针对高精度加速度传感器测试精度的标定难题,文章提出在气浮台上设置比对梁的方法,通过激光测振仪和高精度加速度传感器对同一测点进行测量,并将两者的测量结果进行比对分析,以标定高精度加速度传感器的低量级测试精度。同时设计试验对手头现有的微振动加速度传感器进行标定以验证该方法的有效性,试验结果表明:利用激光测振仪标定现有高精度加速度传感器得到的比对结果符合预期;高精度加速度传感器测得的时域波形及频域波形与激光测振仪测得的基本一致,比对偏差在10%左右,满足标定方法要求。

Calibration of the high accuracy acceleration sensor used in micro-vibration test

The micro-vibration acceleration sensor can measure as low an acceleration as 10-5g or even in a lower level, but its dynamic calibration of the acceleration in that level is a hard issue with the normal technology to garantee the accuracy and the precision of the measurement. To solve this prolem, this paper proposes a combined approach for calibration:first, set up a beam as the control object, and install the acceleration sensor on it; then use the laser vibrometer and the acceleration sensor for the measurement at the same point on the beam; finally, compare the measurement results to determine the accuracy of the acceleration sensors. We have also designed an experiment to calibrate a predefined acceleration sensor to show the effectiveness of this method. It is indicated that the laser vibrometer is a good instrument for calibration, and the comparison result for the predefined sensor is satisfatory; the almost same results are obtained in both ways not only in the time domain but also in the frequency domain, and their relative deviation is as low as about 10%, which satisfies the demand of the calibrating method.