力传感器动态标定及其精度分析研究

RESEARCH ON DYNAMIC CALIBRATION OF FORCE SENSOR AND ITS PRECISION ANALYSIS

对一种压电晶体力传感器动态标定系统进行了研究。首先介绍了这种动态力传感器标定系统的原理和构成;然后用区间算法分析了标定系统的精度,推导出了标定精度的具体表达式;最后对标定系统进行了大量的实验研究,比较了对标准质量块进行有悬挂和无悬挂安装两种实验方案的效果,研究了系统附加质量随频率变化的特性以及其他安装过程对标定结果的影响。研究表明:有悬挂安装法的一致性较差,对实验结果影响较大,无悬挂安装法的一致性较好;在中低频段,系统的附加质量变化幅度很小,力传感器的灵敏度也较为稳定,在高频段,系统的附加质量随标定频率的增加有显著增加,力传感器的灵敏度也有一定增大。这表明,在较高频带上进行实验时,力传感器的灵敏度有必要进行适当修正。

The research on a dynamic calibration system for piezoelectric force sensor is set forth. Firstly, the principle and outline of the system are introduced, and then the precision of the system is analyzed by using interval algorithm and the related formulae are derived. Finally, a lot of experiments are conducted on many aspects for the calibration system, especially on the comparison of installation manners of standard mass, the change of additive mass with respect of frequency, and other influence factors due to installation. The research results show that the installation of standard mass without hanging string is more practicable than that with hanging string; the change of the additive mass is rather small and the sensitivity of the force sensor remains nearly constant in low to medium frequency ranges, but both of them have some increase in high frequency range. This indicates that the sensitivity of force sensor should be modified in the high frequency range.