Studies on position detection of permanent magnet spherical stepper motor based on machine vision

This paper introduces a vision-based position detection method for spherical stepper motor. For the absolute orientation information of the rotor, a new grid pattern and new image analysis method to get the characteristic points are presented. According to the location of the characteristic points and methods in photogrammetry, the rotation matrix can be obtained, so the goal of position detection can be achieved. OpenGL is used to simulate the grid pattern image on the surface of the rotor. The experimental results indicate the feasibility of this method.