基于LabVIEW的零相位滤波器在碰撞实验中的应用

针对碰撞实验的信号特点,分析和设计了一种零相位滤波器.结合虚拟仪器软件平台LabVIEW,对采集到的原始信号序列应用时域延拓算法构造新序列,同时利用窗函数法设计零相位滤波器的参数.然后参照汽车碰撞实验法规要求,选取相应的频率等级进行滤波,滤波后再删除扩展序列.实验结果表明,和传统滤波器相比零相位滤波器不仅能够避免相位延时,而且更好地消除了信号起始端的波形失真.

Application of Zero-Phase Digital Filter Based on LabVIEW in Impact Test

Aiming at the signal characteristic of impact test,a zero-phase digital filter was analyzed and designed.Based on the virtual instrument software LabVIEW,a new signal sequence was constructed from the original data using the time domain extension algorithm,and the parameters of the zero-phase filter were determined by the method of window function.Then,the corresponding frequency rank was selected according to the regulation of automotive crash test.After the filter,the extension sequence was deleted.The test results have shown that the zero-phase digital filter,compared with usual digital filters, can not only avoid phase-shifting,but also improve the wave distortion of start section.