线阵相机的图像校正

Image Correction of Linear Array Camera

针对在零件的高精度尺寸测量中,线阵CCD相机的图像采集与零件运动的同步问题进行研究。对采用伺服电机和运动控制卡的同步方法进行了分析,提出了采用普通异步电机与编码器组合的控制方法;研究了运动控制系统和相机采集线率之间的关系,设计了基于非等步长的同步控制方式。根据线阵相机图像采集的特点,以标准圆形目标作为标定目标,提取了芯片方向和运动方向的直径参数,实现了物像关系和校正插值系数标定;设计了线性插值算法,可以对任意形状的目标成像进行校正。实验结果表明,该方法简单易行,成本低,可以有效地校正线阵CCD由于运动造成的拉伸变形。

For high precision size measurement of parts,the synchronization of linear array CCD camera image acquisition and parts movement is researched.The synchronization method using servo motor and motion control card is analyzed,and a control method is proposed with asynchronous motor and encoder.The relationship between the motion control system and the camera line rate is studied,and synchronization control of unequal step is designed.According to image acquisition characteristics of linear array camera,diameter parameters on chip direction and motion direction of a standard circular target is extracted,realizing calibration of object image ratio and interpolation correction factor.A linear interpolation algorithm is designed that any shape of the target imaging can be corrected according to correction factor.Experimental results show that the method can effectively correct image deformation of tension for linear array CCD with low cost.