Smart measurement automation in automotive with ŠKODA AUTO
“Hexagon’s fully robotic measuring cells are the first embodiment of our cooperation in the field of optical measurement, but it is already clear that this is just the beginning. We would like to continue other projects as soon as possible, and use the HxGN Robotic Automation Software for in-line and at-line measurement.”
Tailor-made smart solution
The measuring cell itself is based on robotic absolute measurement powered by the large-volume measuring capabilities of Hexagon’s advanced laser tracker and 3D laser scanner technology.
“These systems are the real key to productive and highly accurate robotic measurement”, explains Jaroslav Veselý, who leads Hexagon’s Manufacturing Intelligence division in the Czech Republic. “The Leica Absolute Tracker AT960 is capable of six degrees of freedom (6DoF) measurement as standard, allowing the use of a 3D laser scanner or probe from up to 60 metres away."
“Ensuring fully automated control of the dimensions, shapes and positions of measured elements is then just a matter of programming using a unique combination of integrated Hexagon accessories within the cell – from interconnected metrology and programming software, selected rotary tables and flexible fixtures to the new cell control system architecture. The system as configured ensures fast data exchange between all peripherals and therefore enables the automatic creation of measuring programs based on CAD data of parts and jigs, as well as measurement simulation, the precise positioning of clamping jigs according to reference points, and last but not least the fast evaluation of large volumes of scanned data into graphically presented measurement results.”
The robotic measuring cell concept now in place in Mladá Boleslav arose from close cooperation between ŠKODA AUTO and Hexagon, and the resulting solution that was installed within a few months is a prototype tailored specifically to the needs of the measuring centre in this location. The system was designed to deliver the versatility the centre needed, with an installed tool changer unit allowing for direct automated switching between high-speed scanning and more accurate tactile measurement. This variability means the system will always be able to perform measurement of difficult-to access areas, such as openings, in a way that would simply not be possible for a less bespoke solution.
Extended use for the FIVE U-nique fixturing system
The smart cells also contain two workstations with rotary tables that use the flexible magnetic FIVE U-nique fixturing system, which allows accurate fixtures to be rapidly built for an unlimited number of part configurations to provide support and reference to the workpiece. The FIVE U-nique system provides considerable flexibility to automated measurement processes due to its reduced installation time, allowing for fast changes between configurations.
The reference position of each part-holding fixture is automatically determined from the CAD data of the part. The robot enters this position with a special tool from the tool changer and thus determines the final position and height of the fixture for the location. Thanks to this, a quick readjustment of the jigs for all measured parts is ensured, which significantly reduces the financial demands of acquiring and storing individual fixed configuration jigs for every part.
The accuracy of the jig placement is defined by the accuracy of the measuring system, in this case a high accuracy laser tracker and scanner. This system measures the position of the robot as it positions the part-holding fixtures, and subsequent iteration ensures zero deviation from the reference position. The well-established FIVE U-nique system has previously been used to position parts exclusively in coordinate measuring machines, but this new concept developed especially for ŠKODA AUTO demonstrates how this trusted solution can still play a role in the world of smart manufacturing.
Service and support as standardInstalling a tailor-made automated control measurement solution using laser trackers is already a challenging proposition. In this case, the installation was even more complicated because of the Covid-19 pandemic. However, thanks to the professional approach and skills of local Hexagon representatives, the project was successfully implemented within an acceptable timeframe.
Following this successful implementation, ŠKODA AUTO continues to credit their strong partnership with Hexagon to the constant support of Hexagon’s service technicians and application engineers, supported by an accessible and user-friendly training system.