中文摘要：

介绍了永磁球形步进电动机的基本结构及基于机器视觉的球形电机位置检测方法。在电机转子表面喷涂用伪随机编码生成的网格图，图像传感器获取转子图像。通过分析所获取的图像，得到特征点在固联于转子球的坐标系下的坐标。图像传感器标定后得到的参数，可以计算出图像中的特征点在参考坐标系下的坐标。利用这些点在不同坐标系下的坐标，得到2个坐标系间的旋转矩阵，即确定了球形转子旋转后的空间位置。实验结果表明该方法的有效性。该方法可以用于实现闭环控制球形电机。

英文摘要：

The structure of permanent magnetic spherical stepper motor （PMSS） and the method of measuring rotor position based on machine vision are discussed. The grid pattern was painted on the surface of the rotor according to the pseudorandom encoder and the camera captured the image of rotor. By analyzing the image of rotor, the coordinates of characteristic points in the coordinate system fixed on the rotor were derived. The coordinates of these points in the reference frame were also derived after the camera was calibrated. The rotation matrix can be obtained by calculating the coordinates of the points. The position of rotor was determined after rotation. Experimental results show the validity of the method. The method can be used to realize the feedback control of PMSS motor.