Dimensional measurements in production line: a comparison between a custom-made telecentric optical profilometer and on-the-market measurement systems

The focus of this study is to discuss the metrological performance of a first prototype of a vision-based measurement system targeted to in-production dimensional quality control of turned parts. The instrument exploits telecentric optical profilometry, is characterized by short inspection time and is suitable for automated charge/discharge of the parts to be inspected. Section II discusses those mechanical arrangements targeted to optimize images acquired as well as the main issues that eventual mechanical misalignments of components might introduce in the quality of images. Section III describes a comparison analysis performed on measurements collected both with the aforementioned instrument and other on-the-market devices commonly used in production line. The data acquired are presented in section IV and were useful to evaluate the metrological performance of each instrument and the combination of the variability of the instruments and the variability of the parts.