Digital Eyes Replace Inspection Templates in Shipbuilding

An inline 3D system delivers real-time data to the press. This is intended to ensure the quality of forming processes in shipbuilding, increase process reliability, and reduce quality fluctuations.

A semi-automated process chain is set to make the cold plastic forming of steel sheets in shipbuilding more precise and efficient. In the joint project DIKUQ, researchers at the Fraunhofer Institute for Applied Optics and Precision Engineering IOF have developed an inline 3D measuring system. According to a Fraunhofer press release, the core component is a high-speed 3D sensor network with synchronized cameras and projectors. It can capture measurement volumes of up to 4 m × 2 m × 0.5 m in < 0.5 s and use triangulation to reconstruct a precise 3D model.

A surface-based measurement method with structured light in the near-infrared range is used. According to the researchers, a pattern is projected onto the sheet metal, the distortion of which allows conclusions to be drawn about the geometry. The system uses the data to generate an automated target/actual comparison, which is projected directly onto the workpiece. “The worker can immediately see where reworking is needed,” says Dr. Christoph Munkelt from Fraunhofer IOF. Physical inspection templates are no longer necessary, as a digital reference is available instead.

Opportunities for Other Industries

Continuous feedback is intended not only to reduce quality fluctuations, but also to make complex work steps traceable. In the long term, the concept is also to be transferred to other industries with large, individually manufactured components, such as aerospace or architecture.

Background: When bending sheet metal weighing several tons, the final geometry is often determined by the experience of the workers. Manufacturing processes sometimes have to be interrupted to check deviations manually. As a result, processes from series production have so far been difficult to transfer to one-off production in shipbuilding. DIKUQ aims to change this.

The project is coordinated by Ostseestaal GmbH & Co. KG and involves Fraunhofer IOF, the Fraunhofer Institute for Large Structures in Production Engineering IGP, the University of Rostock, and MSR-Service GmbH.

This is a partly automated translation of this german article.