Measurement procedure based on spectrally resolved light and photogrammetric methods for dynamic 6D coordinate measurements in large volumes (Lambda-GPS)

• Applicant: Professor Dr.-Ing. Robert Heinrich Schmitt
• Subject Area: Production Automation and Assembly Technology
• Term: from 2016 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 322750896

The assembly of large components, e.g. from aircraft, railway or ship industry, differs significantly from the assembly of components of smaller dimensions. In particular the handling of the components is challenging due to their size and connected properties (e.g. weight, stiffness). Newer developments aim for a flexible and automated assembly of large components. Static devices will be substituted by a combination of handling systems, e.g. collaborative robots, and external measurement systems. The challenge is in the synchronization of the handling systems, which requires the knowledge of the absolute pose of the end-effector in the reference system. External measurement systems with much lower measurement uncertainty than the measurement systems integrated into the robot, enables to measure the absolute robot pose and therefore, to increase the absolute robot accuracy. The metrology system requirements are to cover the space of the production line and to measure the pose of several end-effectors at the same time with a low measurement uncertainty and a high measurement rate. This requires specialized metrology systems. The meanwhile established term Large Volume Metrology (LVM) comprises a class of mobile, optical measurement systems, which are specially developed to fit the requirements of the manufacturing and assembly of large components (>1m3). Im Rahmen des Forschungsvorhabens gilt es als Zielvorgabe, gegenüber der ersten Voruntersuchungen, das Messvolumen auf 1m3 zu vergrößern, die Messwertstreuung um den Faktor 10 zu reduzieren und eine Messrate von 80Hz (Verdopplung gegenüber iGPS) zu erreichen. The goal is to investigate and further develop a cost efficient measurement procedure based on spectrally resolved light and photogrammetric methods for dynamic 6D coordinate measurements in large volumes. This measurement procedure and the respective measurement system enable to cover the space of the production line and to measure the pose of several end-effectors at the same time with a low measurement uncertainty and a high measurement rate. The objectives of this research project are to increase the measurement volume to 1m^3, to reduce the measurement variation of a factor 10 and to reach a measurement rate of 80Hz compared to the initial experiments. The approach to achieve the objective is: 1) Physical modelling and simulation of the measurement procedure 2) Realization of the measurement procedure in form of a measurement system 3) Systematic investigation and optimization of the measurement procedure and system, in particular under consideration of working volume, measurement rate and uncertainty.

• DFG Programme: Research Grants