联合时变低通与改进形态学滤波的智能在线称量方法研究

Intelligent online weighing by jointed time-variant low-pass and improved morphological filter

针对检重秤在复杂工业生产环境下,受机械传动、被测物体自身振动和外界随机扰动影响导致的传感器输出信噪比低、称量准确性难以满足要求等问题,提出一种联合时变低通与改进形态学的快速数据处理新方法:时变低通滤波器作为一级滤波,通过在信号跃变时,迭代优化滤波器参数,使边沿信号得以快速响应,有效消除冲击干扰,并抑制称重信号在滤波过程中的相位失真;然后采用改进形态学滤波器进行二级滤波,通过选择零值线性结构元素,并优化结构元素长度以及操作算子的权值系数,加快了动态称重的响应速度。实验结果表明,该方法能有效抑制各类干扰影响,提高测量准确度,最终实现运行速度达120 m/min,最大秤量400.0 g,满足国家标准《GB/T 27739—2011自动分检衡器》XIII级要求的检重秤搭建。

The signal of checkweigher is affected by vibrations rising from the mechanical transmission systems,the measured object itself and other random interferences.As a result,the signal-to-noise ratio of the sensor output is exceptionally low,and the weighing results are difficult to meet the requirements of the national standards.To solve these problems,this paper combines the advantages of time-variant low-pass filter and morphological filter,and proposes a novel fast data processing method.The time-variant low-pass filter is used for one-stage filtering.The filter parameters are optimized and adjusted iteratively when the signal changes,so that the edge signal can respond quickly,the impact interference can be eliminated effectively and the phase distortion of the weighing signal in the filtering process can be suppressed.Then,an improved morphological filter is used to conduct the secondary filtering.By selecting zero-value linear structural elements,and optimizing the length of structural elements and the weight coefficient of the operator,the response speed of dynamic weighing is accelerated.Experimental results show that the proposed method can effectively suppress various interferences and improve the weighing accuracy.Finally,a checkweigher system is constructed in this paper,which can achieve a maximum operating speed of 120 m/min and a maximum weighing of 400.0 g.It meets the requirements of the national standard"GB/T 27739-2011 Automatic Catchweighing Instruments"category XIII Scale.