Metrology by Image: Discussing the Accuracy of the Results

Abstract

The development of new inspection techniques have been studied due to their important role in ensuring the quality of products and services. Achieving technical specifications of products considering acceptance criteria requires knowledge of assured inspection methods. Inspection techniques have evolved expressively, lacking, however, in some cases, of certified standardization. The past ten years have experienced considerable development of inspection methods. In part, this is due to the need to meet the security and reliability requirements for consumer protection. Moreover, the extraordinary advances in electronics and computers were also important factors for this advance. In this context visual inspection by images is being applied in many applications, allowing the identification of innumerous product features, like cracks, corrosion, distortion, misalignments, porosity, among others. But, inspections and measurements require calibration of instruments, devices and systems. In order to obtain confident measurements it is important to study and specify the suitable lighting system, camera, lens and principally the best computer measurement algorithms. Thus the aim of this paper is to discuss the relevance of the main parameters that influence the measurement of images using computer vision techniques.