3D DIC is an optical noncoherent full-field optical technique that enables the measurement of shape, displacements (u,v,w) and strains (εxx, εyy, εxy) of a mechanical structure subjected to an external force. During investigations of large engineering structures (e.g., wind turbine blades), a single 3D DIC system is insufficient to deliver the information from the entire object. Hence multi 3D DIC systems should be used and the output information from all systems must be combined into a single coordinate system. This task is relatively simple if each system’s Field-of-Views (FoV) partially overlap. The task gets much more complicated if the FoVs of each system are separated. In such a case, an additional system defining reference coordinate system is required. In this work, we analyse the possibility of using a laser tracker system, an optical ranging method that provides a common reference coordinate system to FoVs distributed in space. Such an approach supporting multi-3D DIC measurements requires specific calibration targets and additional calibration procedures to deliver reliable and accurate results. The work presents the full calibration and data processing path and an experimentally estimated accuracy for the technique.
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