论文部分内容阅读
为减小圆光栅测量过程中叠栅条纹信号的细分误差,提出了一种对叠栅条纹采样信号进行参数辨识与偏差补偿的方法。该方法运用遗传算法参数辨识理论,不受信号模型参数初值选取影响,寻优特性和适用性良好,使复现的信号模型较好地拟合原始采样信号。信号采样实验中控制光栅匀速转动,采样两个栅距内的周期信号,其次对采样得到的离散数据进行频谱分析,建立光栅信号的数学模型,进而通过遗传算法对引起细分误差的信号参数进行识别并对细分误差进行数值补偿。实验结果表明,遗传算法对构建的信号模型参数辨识准确;对比补偿前后李萨如图形,验证了该方法对叠栅条纹信号正弦性误差具有良好的补偿效果;检测单个栅距内的细分误差,补偿前后误差值由10.65″减小到3.31″。该方法适用于光栅编码器等位移测量系统,保证测量精度和可靠性。
In order to reduce the subdivision error of moire signal during the measurement of circular grating, a method of parameter identification and offset compensation for the moire signal is proposed. The method uses genetic algorithm parameter identification theory, which is not influenced by the selection of the initial parameters of the signal model parameters. The optimization characteristics and applicability are good, so that the signal model of the recurrence is better fitted to the original sampling signal. In the signal sampling experiment, the control grating is rotated at a constant speed to sample the periodic signals in two gage intervals. Secondly, spectrum analysis of the sampled discrete data is carried out to establish the mathematical model of the grating signal. Then, the signal parameters that cause subdivision error are calculated by genetic algorithm Identify and compensate numerically the subdivision error. Experimental results show that genetic algorithm can accurately identify the parameters of the constructed signal model. Compared with the Lissajous figure before and after compensation, it verifies that the method has a good compensation effect on the sine error of the moire signal. The subdivision error , The error before and after compensation decreased from 10.65 “to 3.31”. The method is suitable for grating encoder displacement measurement system to ensure measurement accuracy and reliability.