采样点选择对动态汽车衡称量精度的影响

Influence of Sampling Points on the Precision of Weigh-in-Motion

为了提高动态称重的精度,提出一种选取有效采样点减小误差的方式.该方式选用有限冲击响应数字滤波的方法设计数字滤波器,并利用Matlab软件进行了仿真.经过滤波后的采样信号,将重量信号大于3Hz以上的全部滤去,消除了汽车经过秤台时的各种干扰信号;保留有用的汽车轴重信号,准确提取出有效数据称量段;再采用3σ准则去除粗大误差,对去除粗大误差后的数据求和,然后取平均值作为经过秤台的汽车轴重测量值.对实验结果的分析表明:通过选取有效采样点,可使动态汽车衡在50%载荷时的称量精度提高到1%以内.

In order to improve the accuracy of weigh-in-motion, the effective way of selecting sampling points is presented to reduce error. A digital filter is designed with FIR and simulated with Matlab software. After filtering, the weight signals higher than 3 Hz and all kinds of disturbing signals are eliminated when the car passing through the scales, and then the effective data are picked up accurately. The criterion of 3 standard deviation is used to remove gross errors, and then the data are averaged as the measured weigh-in-motion value. The experimental results show that, by choosing the effective sampling points, the accuracy of dynamic automotive value at 50% load can reach 1%.