A two-step method for spatial circle orientation with a structured light vision sensor and error analysis

Abstract

A novel two-step method for spatial circle orientation with a structured light vision sensor is proposed for a 3D flexible visual inspection system guided by an industrial robot. Firstly the z coordinate of a spatial circle center is estimated, secondly the x and y coordinates are estimated with the center orientation relative to the camera optic center, and then its radius is computed. Simultaneously, the x, y and z coordinate orientation errors are analyzed in detail. It shows that the method is feasible and valid, and the orientation accuracy for the spatial circle exceeds 0.15 mm by experiment. It eliminates the bottleneck of the traditional orientation method with a stereovision sensor, and greatly expands the application of the structured light visual inspection system.