Distortion analysis in an omnidirectional image sensing system for assembly (OISSA)

In assembly, part misalignment must be detected and compensated for during the mating period, regardless of the complexity of a cross-sectional shape. In order to achieve these objectives, we have proposed a novel omnidirectional image sensing system for assembling parts with complicated shapes (OISSA), consisting of a pair of an inside-conic and an outside-conic mirror, a pair of plane mirrors, and a CCD camera. This system, however, has a distortion that varies with sizes and shapes of the parts and seriously affects the measurement accuracy. The distortion, therefore, needs to be compensated for in order that the sensing system is capable of detecting misalignments between mating parts, regardless of various shapes and sizes of the parts. In this paper, we analyze distortion features of the sensing system and propose a method for compensating the distortion. The feasibility of compensating the distortion will be also shown through simulations