基于载荷重构的冲击力校准方法

Impact force calibration method based on load reconstruction

在落锤式冲击力校准系统中,针对非刚体的落锤测量点与撞击点的冲击力不相等会产生测量误差的问题,提出了基于载荷重构的冲击力校准方法。该方法采用r阶累加预测模型对测量响应进行滤波;通过落锤核函数矩阵的正则化,建立测量点与撞击点之间的载荷重构模型,实现冲击力测量误差的补偿。利用该方法进行冲击力测量实验,实验表明该方法的峰值相对误差(PRE)为0.6%,相对误差(RE)为3.1%;传统测量方法的PRE为5.7%,RE为6.8%,该方法的PRE和RE分别比传统测量方法改善89.2%和54.8%。该方法能有效降低冲击力的测量误差。

In a dropping hammer type impact force calibration system,aiming at a measurement error problem caused due to the impact force at unrigid body hammer’s measurement point being not equal to that measured at impact point,an impact force calibration method was proposed based on load reconstruction.Firstly,the measurement response at the measured point of hammer was filtered with a r order cumulative prediction model.Secondly,the load reconstruction model between measurement point and impact one was established through the regularization of the hammer kernel function matrix to realize compensation of impact force measurement error.The test results showed that the peak relative error(PRE)and the relative error(RE)of the proposed method are 0.6%and 3.1%,respectively,while those of the traditional method are 5.7%and 6.8%,respectively,so the proposed method can reduce PRE by 89.2%and RE by 54.8%compared with the traditional method;the proposed method can effectively reduce measurement error of impact force.