Endoscopic fringe projection for in-situ inspection of a sheet-bulk metal forming process

Downloadstatistik des Dokuments (Auswertung nach COUNTER):

Matthias, S.; Kästner, M.; Reithmeier, E.: Endoscopic fringe projection for in-situ inspection of a sheet-bulk metal forming process. In: Proceedings of SPIE - The International Society for Optical Engineering 9525 (2015), 952513. DOI: https://doi.org/10.1117/12.2184746

Version im Repositorium

Zum Zitieren der Version im Repositorium verwenden Sie bitte diesen DOI: https://doi.org/10.15488/1758

Zeitraum, für den die Download-Zahlen angezeigt werden:

Jahr: 
Monat: 

Summe der Downloads: 350




Kleine Vorschau
Zusammenfassung: 
Sheet-bulk metal forming is a new production process capable of performing deep-drawing and massive forming steps in a single operation. However, due to the high forming forces of the forming process, continuous process control is required in order to detect wear on the forming tool before production quality is impacted. To be able to measure the geometry of the forming tool in the limited space of forming presses, a new inspection system is being developed within the SFB/TR 73 collaborative research center. In addition to the limited space, the process restricts the amount of time available for inspection. Existing areal optical measurement systems suffer from shadowing when measuring the tool's inner elements, as they cannot be placed in the limited space next to the tool, while tactile measurement systems cannot meet the time restrictions for measuring the areal geometries. The new inspection system uses the fringe projection optical measurement principle to capture areal geometry data from relevant parts of the forming tool in short time. Highresolution image fibers are used to connect the system's compact sensor head to a base unit containing both camera and projector of the fringe projection system, which can be positioned outside of the moving parts of the press. To enable short measurement times, a high intensity laser source is used in the projector in combination with a digital micro-mirror device. Gradient index lenses are featured in the sensor head to allow for a very compact design that can be used in the narrow space above the forming tool inside the press. The sensor head is attached to an extended arm, which also guides the image fibers to the base unit. A rotation stage offers the possibility to capture measurements of different functional elements on the circular forming tool by changing the orientation of the sensor head next to the forming tool. During operation of the press, the arm can be travelled out of the moving parts of the forming press. To further reduce the measurement times of the fringe projection system, the inverse fringe projection principle has been adapted to the system to detect geometry deviations in a single camera image. Challenges arise from vibrations of both the forming machine and the positioning stages, which are transferred via the extended arm to the sensor head. Vibrations interfere with the analysis algorithms of both encoded and inverse fringe projection and thus impair measurement accuracy. To evaluate the impact of vibrations on the endoscopic system, results of measurements of simple geometries under the influence of vibrations are discussed. The effect of vibrations is imitated by displacing the measurement specimen during the measurement with a linear positioning stage. The concept of the new inspection system is presented within the scope of the TR 73 demonstrational sheet-bulk metal forming process. Finally, the capabilities of the endoscopic fringe projection system are shown by measurements of gearing structures on a forming tool compared to a CAD-reference. © 2015 SPIE.
Lizenzbestimmungen: Es gilt deutsches Urheberrecht. Das Dokument darf zum eigenen Gebrauch kostenfrei genutzt, aber nicht im Internet bereitgestellt oder an Außenstehende weitergegeben werden. Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
Publikationstyp: BookPart
Publikationsstatus: publishedVersion
Erstveröffentlichung: 2015
Die Publikation erscheint in Sammlung(en):Fakultät für Maschinenbau

Verteilung der Downloads über den gewählten Zeitraum:

Herkunft der Downloads nach Ländern:

Pos. Land Downloads
Anzahl Proz.
1 image of flag of Germany Germany 201 57,43%
2 image of flag of United States United States 61 17,43%
3 image of flag of China China 22 6,29%
4 image of flag of No geo information available No geo information available 8 2,29%
5 image of flag of Korea, Republic of Korea, Republic of 8 2,29%
6 image of flag of Sweden Sweden 7 2,00%
7 image of flag of Greece Greece 6 1,71%
8 image of flag of United Kingdom United Kingdom 6 1,71%
9 image of flag of Canada Canada 4 1,14%
10 image of flag of Russian Federation Russian Federation 3 0,86%
    andere 24 6,86%

Weitere Download-Zahlen und Ranglisten:


Hinweis

Zur Erhebung der Downloadstatistiken kommen entsprechend dem „COUNTER Code of Practice for e-Resources“ international anerkannte Regeln und Normen zur Anwendung. COUNTER ist eine internationale Non-Profit-Organisation, in der Bibliotheksverbände, Datenbankanbieter und Verlage gemeinsam an Standards zur Erhebung, Speicherung und Verarbeitung von Nutzungsdaten elektronischer Ressourcen arbeiten, welche so Objektivität und Vergleichbarkeit gewährleisten sollen. Es werden hierbei ausschließlich Zugriffe auf die entsprechenden Volltexte ausgewertet, keine Aufrufe der Website an sich.