scholarly journals Fringe Projection Profilometry in Production Metrology: A Multi-Scale Comparison in Sheet-Bulk Metal Forming

Sensors ◽  
2021 ◽  
Vol 21 (7) ◽  
pp. 2389
Author(s):  
Lennart Hinz ◽  
Sebastian Metzner ◽  
Philipp Müller ◽  
Robert Schulte ◽  
Hans-Bernward Besserer ◽  
...  

Fringe projection profilometry in combination with other optical measuring technologies has established itself over the last decades as an essential complement to conventional, tactile measuring devices. The non-contact, holistic reconstruction of complex geometries within fractions of a second in conjunction with the lightweight and transportable sensor design open up many fields of application in production metrology. Furthermore, triangulation-based measuring principles feature good scalability, which has led to 3D scanners for various scale ranges. Innovative and modern production processes, such as sheet-bulk metal forming, thus, utilize fringe projection profilometry in many respects to monitor the process, quantify possible wear and improve production technology. Therefore, it is essential to identify the appropriate 3D scanner for each application and to properly evaluate the acquired data. Through precise knowledge of the measurement volume and the relative uncertainty with respect to the specimen and scanner position, adapted measurement strategies and integrated production concepts can be realized. Although there are extensive industrial standards and guidelines for the quantification of sensor performance, evaluation and tolerancing is mainly global and can, therefore, neither provide assistance in the correct, application-specific positioning and alignment of the sensor nor reflect the local characteristics within the measuring volume. Therefore, this article compares fringe projection systems across various scale ranges by positioning and scanning a calibrated sphere in a high resolution grid.

2012 ◽  
Vol 504-506 ◽  
pp. 1005-1010 ◽  
Author(s):  
Christoph Ohrt ◽  
Wito Hartmann ◽  
Johannes Weickmann ◽  
Markus Kästner ◽  
Albert Weckenmann ◽  
...  

Sheet bulk metal forming is a new forming technology, currently developed by several companies and research institutes. It creates high demands on the inspection of parts and tools, especially in the field of in-situ abrasion detection of the forming tool and its impacts on the work piece. This manuscript introduces two optical testing methods for fulfilling these inspection tasks: On the one hand the endoscopic fringe projection as a flexible small scale optical measurement principal with high depth of focus and accuracy for the acquisition of filigree form elements for a continuous abrasion determination and one the other hand the multi-scaled fringe projection for a holistic one shot measurement of the work piece for an adapted, multiscale deviation analysis. The development and advantages of both systems for the sheet bulk metal forming process are shown as well as potentials of the combination of the both systems close to the proposed application next to the production line.


2015 ◽  
Vol 639 ◽  
pp. 291-298 ◽  
Author(s):  
Andreas Loderer ◽  
Martin Timmermann ◽  
Steffen Matthias ◽  
Markus Kästner ◽  
Thomas Schneider ◽  
...  

In order to fulfil today’s demands on fast, efficient and sustainable production processes the sheet-bulk metal forming is being developed as a new forming technology within the scope of the SFB/Transregio 73. Characteristically for the sheet bulk metal forming is a three dimensional material flow, which allows for extensive freedom in the design process. To ensure maintaining all the advantages, provided by sheet-bulk metal forming, new inspection concepts for the produced parts as well as for the forming tools have to be developed. For a production-related inspection of produced parts a multi-sensor fringe projection system is under development, which will be employed to detect deviations of features’ form and size. With its sensors of varying measuring range and resolution a feature adapted inspection is possible. Additionally an optical fibre sensor is projected to detect small parts of interest in a very high resolution to enhance the possibilities of the multiscale multi-sensor system. A newly developed endoscopic fringe projection system is used to inspect parts that are out of reach for common optical measuring systems such as the forming tool of the process. This allows for a continuous measurement of tool features and thus the detection of slow growing wear. Challenging for measurement tasks in the sheet-bulk metal forming process are not only the complex geometries but also the harsh environmental conditions and especially for the parts’ inspection, the different surface parameters. In this article the surface parameters of the some sheet-bulk metal formed parts and forming tools will be explained, followed by a description of the different measuring systems. Finally an exemplary evaluation of the influence of the surface properties on an optical measuring system will be shown.


Author(s):  
Lorenzo Scandola ◽  
Christoph Büdenbender ◽  
Michael Till ◽  
Daniel Maier ◽  
Michael Ott ◽  
...  

AbstractThe optimal design of the tools in bulk metal forming is a crucial task in the early design phase and greatly affects the final accuracy of the parts. The process of tool geometry assessment is resource- and time-consuming, as it consists of experience-based procedures. In this paper, a compensation method is developed with the aim to reduce geometrical deviations in hot forged parts. In order to simplify the transition process between the discrete finite-element (FE) mesh and the computer-aided-design (CAD) geometry, a strategy featuring an equivalent surrogate model is proposed. The deviations are evaluated on a reduced set of reference points on the nominal geometry and transferred to the FE nodes. The compensation approach represents a modification of the displacement-compatible spring-forward method (DC-SF), which consists of two elastic FE analyses. The compatible stress originating the deviations is estimated and subsequently applied to the original nominal geometry. After stress relaxation, an updated nominal geometry of the part is obtained, whose surfaces represent the compensated tools. The compensation method is verified by means of finite element simulations and the robustness of the algorithm is demonstrated with an additional test geometry. Finally, the compensation strategy is validated experimentally.


CIRP Annals ◽  
2011 ◽  
Vol 60 (1) ◽  
pp. 283-286 ◽  
Author(s):  
M. Merklein ◽  
J. Koch ◽  
S. Opel ◽  
T. Schneider

2012 ◽  
Vol 504-506 ◽  
pp. 969-974 ◽  
Author(s):  
Harald Hetzner ◽  
Stephan Tremmel ◽  
Sandro Wartzack

In sheet bulk metal forming, locally adapted friction properties of the contact tool/workpiece are an appropriate means for the targeted enhancement of the material flow, enabling an improved form filling and lowered forming forces. However, the implementation of desirable friction conditions is not trivial. And further, friction is inseparably linked to wear and damage of the contacting surfaces. This calls for a methodological approach in order to consider tribology as a whole already in the early phases of process layout, so that tribological measures which allow fulfilling the requirements concerning local friction and wear properties of the tool surfaces, can already be selected during the conceptual design of the forming tools. Thin tribological coatings are an effective way of improving the friction and wear properties of functional surfaces. Metal-modified amorphous carbon coatings, which are still rather new to the field of metal forming, allow tackling friction and wear simultaneously. Unlike many other types of amorphous carbon, they have the mechanical toughness to be used in sheet bulk metal forming, and at the same time their friction properties can be varied over wide ranges by proper choice of the deposition parameters. Based on concrete research results, the mechanical, structural and special tribological properties of tungsten-modified hydrogenated amorphous carbon coatings (a-C:H:W) are presented and discussed against the background of the tribological requirements of a typical sheet bulk metal forming process.


Lubricants ◽  
2018 ◽  
Vol 6 (2) ◽  
pp. 42 ◽  
Author(s):  
Marco Lüchinger ◽  
Igor Velkavrh ◽  
Kerstin Kern ◽  
Michael Baumgartner ◽  
Stefan Klien ◽  
...  

2015 ◽  
Vol 651-653 ◽  
pp. 1153-1158 ◽  
Author(s):  
Bernd Arno Behrens ◽  
Anas Bouguecha ◽  
Milan Vucetic ◽  
Sven Hübner ◽  
Daniel Rosenbusch ◽  
...  

Sheet-bulk metal forming is a manufacturing technology, which allows to produce a solid metal component out of a flat sheet. This paper focuses on numerical and experimental investigations of a new multistage forming process with compound press tools. The complete process sequence for the production of this solid metal component consists of three forming stages, which include a total of six production techniques. The first forming stage includes deep drawing, simultaneous cutting and following wall upsetting. In the second forming stage, flange forming combined with cup bottom ironing takes place. In the last stage of the process sequence, the component is sized. To investigate and to improve process parameters such as plastic strain distribution, resulting dimensions and process forces, FEA is performed. Based on these results the developed process is designed.


Sign in / Sign up

Export Citation Format

Share Document