Complex form measurement using optical technology

Optical instruments for measuring surface topography are increasingly being used as coordinate measuring machines (CMMs) to allow them to measure complex three-dimensional components. This project will investigate the use of one such instrument based on the principle of point-autofocusing, but with a 5-axis motion system. The fundamental limitations of the techniques acting as a CMM will be determined and quantified. Specification standards that are applied in the CMM and form measurement fields (e.g. ISO 10360, 12181) will be applied, where possible, to multi-axis point-autofocussing and, where not possible, new procedures will be developed. Methods for calculating uncertainties with the instrument will be investigated, including the principle of a virtual CMM applying a Monte Carlo technique. A number of case study components will be measured to showcase the methods developed, with a focus on gear metrology. This project aims to develop measurement and calibration methodologies for the form measurement of complex engineering components.