Model-based, active inspection of three-dimensional objects using a multi-sensor measurement system

Considering modern manufacturing processes, there is an increasing demand for flexible, fast and precise inspection systems. Usually, the holistic inspection of technical components with a complex three-dimensional surface, like gears, needs to be separated into inspection steps. Different areas on the object need to be verified with respect to varying characteristic specifications, e.g. related to defects or roughness properties. Such manifold inspection tasks can for instance be realized using a multi-sensor measurement system which is also equipped with a multi-axis system to optimally move and rotate each sensor with respect to any desired position at the object’s surface. In order to generate an automatic inspection system, the entire process is defined with respect to a polygonal model of the measurement specimen, such that different sub-regions are connected with different specifications and parameterizations that this region must meet and hence needs to be verified by the inspection system. However, the data acquisition with respect to sub-regions on the model’s surface and the integration of obtained datasets in the model’s coordinate system is only feasible if the transformation of the real object to the model is determined before. Consequently, this needs to be determined in the initialization phase of the overall inspection process.