LOCAL WALL THICKNESS MEASUREMENT OF FORMED SHEET METAL USING FRINGE PROJECTION TECHNIQUE

摘要

An optical system based on fringe projection method has been developed for the measurement of the cross-section area of formed sheet metal, which is generally susceptible of being reduced, and sometimes leads to necking and tearing during forming process. A better understanding of the material and component behaviour is a challenge to experimental measuring methods. To realise such a method the part to be measured is digitised in different orientations by a fringe projection system. With the help of a newly developed inspection technique, the estimation of wall thickness in the critical zones of formed sheet metal part will be implemented by evaluating the measured data, taken in different orientations from the fringe projection system, and the result would be displayed for visualisation. This method allows fast, objective and non-destructive inspection of formed metal sheet and the detection of its defects. This measurement system can be integrated in automated operating procedure for 100% inspection and also enables the speeding up of mass production. This work presents an evaluation strategy and first measuring results.