ARCHIVES of FOUNDRY ENGINEERING Published quarterly as the organ of the Foundry Commission of the Polish Academy of Sciences ISSN (1897-3310) Volume 10 Issue Special1/2010 255-260 49/1 Optical coordinate scanners applied for the inspection of large scale housings produced in foundry technology M. Grzelka a *, J. Chajda a , G. Budzik b , A. Gessner a , M. Wieczorowski a , R. Staniek a , B. Gapiński a , R. Koteras c , P. Krasicki c , L. Marciniak a a Institute of Mechanical Technology, Poznan University of Technology b Department of Machine Design, Rzeszów University of Technology c Volkswagen Polska Poznan *e-mail: miroslaw.grzelka@gmail.com, mioslaw.grzelka@put.poznan.pl, www.zmisp.mt.put.poznan.pl Received 05.03.2010; accepted in revised form 23.03.2010 Abstract The paper presents possibilities of the dimensional and geometry measurement of the large scale casting details with a coordinate measuring technique. In particular, the analysis has been devoted to the measurement strategy in case of the measurement of large scale detail (larger than 1000 mm) made in foundry technology, with the 3D optical scanner. The attention was paid on the possibility created by the advanced software attached to the scanner for measurement data processing. Preparation to the geometrical accuracy analysis of the measured objects consisted of the identification of particular geometrical features based on the large number of probing points, as well as the creation of the coordinate systems derived from the best-fitting algorithms which calculate the inscribed or circumscribed geometrical elements. Analysis of accuracy in every probing point has been performed through the comparison of their coordinates with nominal values set by 3D model. Application of the 3D optical coordinate scanner with advanced measurement software for the manufacturing accuracy inspection is very useful in case of large scale details produced with foundry technologies and allows to carry out full accuracy analysis of the examined detail. Key words: coordinate measuring technique, 3D optical scanners, optical coordinate measurement, large scale measurement, foundry of the large scale details 1. Introduction Large scale details produced in foundry technology have got usually large distances between the measured points of the inspected feature. The features and the examined points reflect the manufacturing accuracy of the detail. Moreover, their accuracy is a crucial characteristics for future functionality and assembleability, and, hence, usefulness of the inspected detail in a final construction or device. The examples are constructions and subassemblies in motor industry, ship or aerospace industry. Metrological description of the critical characteristics which set conditions on the correctness and accuracy of the large scale details and subassemblies, especially those produced in foundry technologies, depends on the applied measuring techniques and devices. The applied measurement strategy is directed to the identification of the specified dimensions and their deviations from the nominal values. In the recent decades, one of the most rapidly developing branches of metrology is the coordinate measuring technique. New solutions like advanced construction of the measuring machines, newly developed materials used for their parts, measurement software combined with the control devices, ultra- precise incremental gauges with positioning devices, and measurement heads and probes ensure the extremely accurate measurement of both small and large scale details. Implementation of the non-contact measuring heads in the ARCHIVES OF FOUNDRY ENGINEERING Volume 10, Special Issue 1/2010, 255-260 255