Real-Time Part Position Sensing

A light stripe vision system is used to measure the location of polyhedral features of parts from a single frame of video camera output. The geometric conditions which assure location of the feature when the light plane intersects three of the features faces are given. Issues such as accuracy in locating the line segments of intersection in the image and combining redundant information from multiple measurements and multiple sources are addressed. In 2. 5 seconds, a prototype sensor was capable of locating a two inch cube to an accuracy one standard deviation of .002 inches .055 mm in translation and .1 degrees .0015 radians in rotation. When integrated with a manipulator, the system was capable of performing high precision assembly tasks.