FIR滤波在汽车动态轴组计量信号处理中的应用

Application of FIR Filtering in Vehicle Dynamic Axis Group Weighing Signal Processing

为了提高轴组式动态称重系统的精度和稳定性,需要采用FIR(finite impulse response)滤波处理方法,过滤高频干扰。通过Matlab仿真,设计了FIR低通滤波器。同时为了保证动态称重良好的实时性,选择了功能强大的STM32F407微控制器芯片,实现了FIR滤波算法。STM32F407微控制器芯片主频高达168 MHz,且内部集成了单周期的DSP指令集和浮点运算单位(FPU,float point unit),可以轻松实现FIR滤波算法。最后,将该FIR滤波算法应用于轴组式动态称重系统,并进行了相关实验验证。实验结果表明:采用FIR滤波后,对系统中由汽车振动、称体晃动等因素引入的干扰信号有明显的滤除作用,称重精度和稳定性均有所提高。

In order to improve the accuracy and stability of axis group type dynamic weighing system, FIR （fi- nite impulse response） filtering method is needed to filter the high frequency interference. The FIR low-pass filter is designed by Maflab simulation. At the same time, in order to ensure a good real-time dynamic weig- hing, a powerful microcontroller STM32F407 is selected to achieve the FIR filtering algorithm. Frequency of STM32F407 is up to 168 MHz, and a single-cycle DSP instruction set and FPU （float point unit） are internally integrated, FIR filtering algorithm can be easily implemented. Finally, the FIR filtering algorithm is applied to axis group dynamic weighing system, and the relevant experimental verification is carried out. The experimental results show that, after filtering, it has obvious filtering effect for the interference signal induced by vehicle vi- bration, scale body sloshing and other factors, and the weighing accuracy and stability are improved.