Microphotogrammetry for 3D strain measurement and microassembly control

In photogrammetry several images of an object taken from different positions in space, are combined to calculate 3D geometrical data. This concept can be scaled down to dimensions in the mm or sub-mm regime. In this paper the application of microphotogrammetry for the measurement of strain fields in material testing is presented. The working principle and an experimental measurement setup are described and results of two application examples are given. Microphotogrammetry is compared with speckle-interferometry as an alternative approach for strain field measurement. As an additional implementation of the microphotogrammetric approach the current state of development of a precision assembly system with a positioning control using CCD-cameras is discussed.