Automotive supplier GEDIA has taken a new approach to quality control by replacing measuring technology based on tactile systems and gauges with full-surface optical 3D coordinate measurement. The implementation of optical metrology systems is making GEDIA more flexible, cutting costs and reducing the time required for measurements.
Founded in 1910, GEDIA Gebrüder Dingerkus GmbH develops and produces structural parts and assemblies for the automotive industry. The company is located in Attendorn, Germany, and has additional production sites in Poland, Spain, China and Mexico and also operates engineering centers in France, U.S.A., and Sweden. All plants manufacture pressed, stamped, and drawn parts for the automotive industry.
Corporate goal of technological leadership
Up until recently, GEDIA had focused on tactile measurement, using coordinate measuring machines and gauges for quality control of assemblies as well as in tool-making. However, this approach to measurement reached its limits as the company grew and expanded its manufacturing locations. The inspection of sheet metal parts became time and labor intensive, as parts had to be transported several hundred meters from the press or fabrication production areas to the central measuring room. To streamline the process, the decision was made to have the measuring system come to the component, instead of transporting the component to the measuring system. However, this would require mobile measuring equipment designed for use in the production environment.
The new quality control approach is an important step in realizing GEDIA’s goal of leading the industry in production technology. In consequence, the changeover from traditional tactile systems to full-surface optical 3D coordinate measurement is being implemented worldwide at all production sites and at all relevant facilities, such as press shops and assembly.
Larger scale production requires shorter measurement times
Like many companies that have to adjust their processes to accommodate increased production levels, GEDIA was challenged to find ways to cut measurement times. At the same time, quality has to be maintained, although cycle times grow shorter and production output increases. However, the relatively slow tactile measurement of parts, which often have complex shapes, means long measurement times and complex logistics, and even then, only a few points on the part are inspected.
In order to manage the rising output quantities and the constant increase in measuring requirements, GEDIA had to outsource a growing number of measurement tasks to external service providers. This situation had two main drawbacks: Not only did it result in high costs, but it also meant that inside knowledge had to be shared with parties outside the company. Thus the aim of the new approach to quality control was that the entire measurement and digitizing expertise should once again be contained within the company’s own workforce.
With this in mind, the quality control and measuring technology experts at GEDIA had four main criteria to consider: The systems needed to deliver full-surface measurements while also being mobile and fast. The company also wanted to regain the complete measuring competence in-house.
The approach to optical measurement technology
After various unsatisfactory trial runs with mobile, tactile devices mounted on articulated arms, it became clear that tactile metrology was not going to meet the company’s needs. It was time to completely rethink the measuring technology used. GEDIA launched the transition from tactile to optical metrology by investing in a mobile ATOS 3D scanner for full-surface optical 3D coordinate measurement. This was an important first step toward the company’s main goal of keeping the technological leadership.
With its fast supply of precise measurement data, the high-resolution optical ATOS 3D digitizer fulfilled the company’s criteria. For all of the various sizes and surface characteristics of the components at GEDIA and even complex measuring tasks, the optical system offered precise 3D coordinates with high data quality, parametric inspection and traceable evaluation, full-surface deviation to CAD, or from part to part, evaluation according to 2D drawings, inspection sections, geometric dimensioning and tolerancing (GD&T)as well as trend analysis and complete, clearly presented measurement reports.
Used for measuring tools and forming dies, but also for the measurement of sheet metal parts, the manual ATOS system quickly demonstrated that GEDIA could significantly benefit from optical measurement technologies. From prototype development to serial production measurement, part analysis, digitizing up to virtual joining of assemblies – all of these tasks were performed by a single technology, as opposed to the much less versatile tactile measuring method.
An additional benefit with full-surface measurement is that it makes efficient tool corrections easier, and as a result, fewer iterations are required before a tool is approved. By measuring the final tool contours with the ATOS scanner, it is also possible to keep the CAD data for the tool up to date. This enables also copy milling of tools based on the ATOS data.
The clear, easy-to-read measurement reports generated from the full-surface data provided an additional benefit: In contrast to pages of tables from test reports with individual measuring points, these provided significantly better readability and clarity and reduced the time required for discussing the results, and allowed any necessary correction steps implemented quickly and efficiently.
Next step: automated optical metrology
The experiences at GEDIA led to an additional requirement to make the process more flexible, and efficient in terms of time and costs and thus GEDIA wanted to have the optical measurement automated while remaining mobile.
When a GEDIA-designed customized measuring cell, with integrated GOM equipment, proved to be a step in the right direction, the company decided to acquire a standardized, automated measuring cell: the ATOS ScanBox. As opposed to a customized solution, the ATOS ScanBox came with all necessary elements required for fully automated 3D digitizing and inspection and all that was required for operating the turnkey measurement cell on site was floor space and a power supply.
Standardized measurement cells at multiple sites
GEDIA’s first ATOS ScanBox was used for production related quality control at the press shop in Attendorn. The core of the measurement cell, developed with precisely such production applications in mind, is the robot guided ATOS Triple Scan 3D sensor. Another advantage for the automotive supplier was that the ATOS ScanBox can be directly operated by production staff, as all measurement and inspection processes up to the measurement report can be quickly and easily achieved made possible by the standard software solution VMR (virtual measuring room), which reproduces the actual environment of the ATOS ScanBox. VMR allows the robot to be operated with simple drag-and-drop commands without use of the robot operating panel and allows part program generation offline using CAD data without a physical part.
In the Attendorn press plant, the ATOS ScanBox has helped cut the measuring times by more than half comparison to the previous tactile measurement solutions exceeding GEDIA expectations and in addition are able to work without expensive measuring gages when using optical measuring technology.
A second ATOS ScanBox is already in use at GEDIA to check the quality of a completely assembled rear-end of a German luxury car. GEDIA has also installed another ATOS ScanBox for the press plant in Poland, and plans to have GOM`s optical metrology installed at all of its sites. Even though the measurement cells are in use in different locations, GEDIA is still able to centralize its quality management: The measurement and inspection processes with the ATOS ScanBox are standardized and can therefore be applied uniformly at the various locations. As a result, the entire quality control process is becoming traceable and transparent.
For more information: www.gom.com