基于E-SPCM的直线电机动子位置高精度测量方法研究

Research on high-precision measurement method of linear motor mover position based on E-SPCM

针对直线电机动子位置测量,引入一种基于扩展采样相位相关法(E-SPCM)的亚像素位移图像检测方法,以提高测量精度和抗干扰性。首先建立了直线电机位置检测系统,通过高速相机实时采集条纹图像序列;其次对条纹图像进行边缘特征提取,利用相位相关得到相邻条纹图像的互功率谱,即动子位置的整像素位移;进而对整像素邻域的互功率谱进行上采样相位相关计算,实现高精度的亚像素位移测量,进一步由系统标定得到实际位移值。对比传统相位相关算法,所采用的方法能够提高测量精度且有很好的噪声抑制性能,最后搭建了实验检测平台,验证了算法的有效性。

To achieve linear motor mover position measurement,a sub-pixel displacement image detection method based on extended sampling phase correlation method(E-SPCM)is proposed to improve measurement accuracy and anti-interference performance.Firstly,a linear motor position detection system is formulated.The stripe image sequences are captured in real time by a high-speed camera.Secondly,the edge feature extraction is performed on the stripe image.The cross-power spectrum of the adjacent stripe image is obtained based on the phase correlation,which is the integer pixel displacement of mover position.Then,the up-sampling phase correlation is calculated based on the cross-power spectrum of the integer pixel neighborhood.The high-precision sub-pixel displacement measurement is realized and the actual displacement value is further obtained by system calibration.Compared with the traditional phase correlation algorithm,the proposed method can improve the measurement accuracy and noise suppression performance.Finally,an experimental detection platform is established to verify the effectiveness of the proposed algorithm.