Oberkochen, Germany | 4th October 2021 | ZEISS Industrial Quality Solutions

As a leading provider of innovative solutions in the field of inline measurement technology such as the new ZEISS AICell trace product category, which combines real-time process monitoring and metrologically traceable inline measurement technology in a single cell, ZEISS knows its customers' requirements and their strategies through its active exchange with them. With funding from the German Federal Ministry of Education and Research (BMBF), ZEISS has researched and developed the concept of an autonomous measurement robot (AuMeRo) in response to these developments in a consortium with partners BMW, the Institute for Metrology, Control and Microtechnology (MRM) at the University of Ulm and the Institute for Laser Technologies in Medicine and Metrology (ILM). A fully functional specimen has already proven this year that the AuMeRo can fully handle tasks such as the inspection of gap dimensions and flushness on unpainted or painted car body parts.

“A rigid production line for a standard product on which the largest possible number of units is produced – this established concept could soon be a thing of the past”, states Manuel Schmid, Product Manager at ZEISS IQS. Increasingly individual customer demands are leading to a growing number of product variants and thus to the need for modularization in their production. Industries particularly affected by this, such as the automotive industry, are therefore planning in the long term to dissolve sequential manufacturing processes with highly specialized stations and replace them with flexibly deployable manufacturing islands.

The AuMeRo is a rectangular platform with wheels at the bottom and a robotic arm with an optical measurement sensor at the top. "Of course, this hardware aspect is not revolutionary in itself," explains Dr. Matthias Karl from Corporate Research at the ZEISS Group. "The key task was to create the necessary intelligence on the software side for autonomous movement to the object, its measurement and data processing." To meet this challenge in the research project, the research partners combined their respective areas of expertise.

The Institute for Metrology, Control and Microtechnology at the University of Ulm has a focus on autonomous driving in collaboration with several car manufacturers. It therefore developed and implemented the navigation solution for the mobile measurement platform, which enables it to move autonomously to the target object while safely avoiding obstacles. The Institute for Laser Technologies in Medical and Metrology researched suitable optical measurement techniques for the special application, focusing on multi-wavelength holography. ZEISS, as the group coordinator, was represented by two departments, ZEISS Industrial Quality Solutions (IQS) and Corporate Research: ZEISS IQS contributed the application-specific optical metrology, while ZEISS Corporate Research handled the movement of the robotic arm, object recognition and measurement pose control using optical image recognition in conjunction with machine learning. The application partner BMW, as one of the leading premium car manufacturers, gave the project a tangible practical context.

"The user selects an object via software, for example a vehicle door, its rough location and then the intended measurement plan. From this point on, AuMeRo acts fully autonomously," explains Manuel Schmid. Object recognition happens via camera and is based on a digital twin of the object. For the actual measurement, the mobile platform is equipped with additional optical sensors: For this purpose, ILM developed a special measurement sensor with advantages for short measurement times and robust environmental influences, which uses multi-wavelength digital holography. In this way, topographic data of an entire area for diffuse and/or specular reflective surfaces can be obtained within one snapshot. After the platform has found and approached the object, the robotic arm moves the measuring head according to the requirements from the measuring program, taking into account the current spatial conditions. "With its ability for autonomous mobility and object recognition, AuMeRo is ready for a future in which mobile, modular manufacturing islands are the norm, and allows measurement to take place wherever and whenever it is needed," Schmid says. "However, it can already play out its full benefits for manufacturers, for example in product audits, where currently measurement and documentation are done manually in the measuring room. With AuMeRo, this is much more efficient, because it is fully automated and reproducible with consistently high quality and informative value of the generated measurement results."

"With the research project, we have been able to demonstrate that the concept works without restriction and can be easily adapted to new objects and measurement plans. This has opened the doors for this technology," says group coordinator Dr. Matthias Karl. Jan-Klaus Dziergwa, Project Manager Car Body Engineering, Quality Management BMW Group, is enthusiastic about the result: "At BMW, we are highly interested in fulfilling individual customer wishes and at the same time continuously increasing the efficiency of our production and quality assurance. This requires innovative methods and technologies, and AuMeRo is an excellent example of this."

With its four brands BMW, MINI, Rolls-Royce and BMW Motorrad, the BMW Group is the world’s leading premium manufacturer of automobiles and motorcycles. The company set the course for the future at an early stage and consistently makes sustainability and efficient resource management central to its strategic direction, from the supply chain through production to the end of the use phase of all products. The BMW Group production network comprises 31 production and assembly facilities in 15 countries; the company has a global sales network in more than 140 countries.

The Institute of Metrology, Control and Microtechnology at the University of Ulm has been working in the field of automated systems with a focus on automated driving for more than 15 years. Currently, more than 15 scientific staff members are involved in this topic. The methodological focus is on basic sensor signal processing of video, LIDAR and radar sensors, information fusion, multi-object tracking, environment modeling with situational understanding and action planning of autonomous systems.

The Institute for Laser Technologies in Medicine and Metrology at the University of Ulm (ILM) conducts research in selected areas of photonics / optics and transfers the technologies developed into industrial and medical practice. The most important fields of application include medicine and dental technology, production metrology, process analytics, agricultural & environmental sensor technology, and sensor technology for autonomous systems.