Digitization gives new impetus to the economy. Manufacturing processes are changing, logistics is being rethought and sales are also finding new ways to reach customers. Especially the constantly increasing automation of work processes is always in the focus of public perception. This is because, in addition to more cost-efficient production and the resulting increase in competitiveness, it leads to job cuts. Even in those domains where human labour has been the most efficient way of production due to their specialisation or complexity, the automated process is gaining more and more ground due to continuous development.
The inevitable consequence is the deserted factory. A dream for every purely economically thinking entrepreneur who no longer has to deal with downtime, fatigue or interpersonal problems. A dystopia, however, for many employees who see their existence threatened. But the economic constraints to which companies are exposed cannot be argued away. Only those who can make a profit will be able to survive in the market in the long term. Without automation and digitalization, this can no longer be achieved today. The consequence: manual assembly must change and take advantage of the opportunities offered by automation. The different strengths of man and machine must be combined so that they complement each other optimally.
The reasons for this are many and varied, but can be easily identified and narrowed down:
- Increasing variety: Customers demand more and more individualisation options. It is becoming more and more difficult for workers to access these at any time and to be able to produce them quickly, requiring long training times and a lot of practice.
- Increasing quality requirements: Wherever manual production is unavoidable, its quality must not be inferior to automated production. However, since human work is often prone to errors, measures are required to enable more efficient quality control.
- Shortage of skilled personnel: The lack of skilled personnel is also noticeable in production. Well trained personnel are hard to find. The constantly increasing requirements described above also make this shortage continuously more acute.
Measures to increase the efficiency of manual production
The goal of upgrading manual production must be an increase in productivity with simultaneous process reliability. Only if it is guaranteed that the quality of the production increases to the same extent as its speed, a corresponding measure is reasonable. An additional challenge is the mastery of the increasingly complex work steps.
The basis of such digital support is data. The constantly increasing automation, sensor technology & actuator technology as well as a more comprehensive system integration lead to the fact that already today comprehensive amounts of information are available in the area of manufacturing. Evaluating and organizing this information and making it available to all those involved, from the worker to the production planner, is one of the most promising approaches to increasing efficiency in manual production. These data offer the possibility for exploratory visualization and finally also for the use of artificial intelligence.
OEE in manual shop floor assembly
How can this approach be transferred to manual assembly and finally be integrated meaningfully into the production process? In most systems, extensive camera technology is used. The storage of visual data of the production process creates a digital shadow of it. This information is used to assist all those involved in production and to provide them with all the information they need to do their job. The individual work steps can thus be output within the framework of an explorative visualization and finally even be linked to an artificial intelligence to form a competent assistant who supports the worker and complements and expands his skills.
The basis for this is future-oriented knowledge management. This requires the integration of the different systems of the shop floor. Worker-centered and application-optimized, these are integrated into the digital assistant as a database for all further processes. Numerous previously independent processes can contribute information and benefit from synergy effects in return. Complete integration is also possible in many places, so that only the digital assistant system is required.
- The data of a CAD software can be stored directly in the assistance system. This makes it available throughout the company. Workers and engineers alike can access the detailed information on each component from any workstation. The visual and technical data also serve as an initial blueprint for checking all workpieces.
- By updating relevant production data management (PDM) information in real time, product lifecycle management (PLM) strategies can be more quickly identified, checked and supported with reliable data. The continuous collection of relevant key figures enables a review of the existing efficiency as well as the control of the usefulness of new measures.
- Quality control within the framework of CAQ is also integrated into the assistance system. The continuous, automatic and real-time updating of all information relevant to the work process offers a whole range of advantages:
- The test plans are always up to date.
- The information is a solid basis for statistical process controls.
- Automatic OK booking replaces manual.
- Error frequencies and error correlations can be detected more quickly and, with appropriate software, even read out automatically from large data sets.
- Accordingly, the approaches of the ERP/APS measures are also made more efficient by the assistance systems. In many companies, automated quality control alone saves 30 percent of production time. Automation and simplification can be achieved:
- Checklists and documentation are automatically filled and read out. They are also available company-wide and improve the verifiability of quality control. This also includes the traceability of installed components by o scanner and o camera.
- The ability to trace critical assembly steps, e.g. through feedback from digital assembly tools or through image documentation using camera technology, allows for more efficient control and error prevention.
- Automatic updates and correct versioning save time and ensure that the system always runs smoothly.
Information as the basis for more efficient manual production
Detailed assembly sequences and their confirmation (Beyond ERP) transfer a large part of the responsibility for a successful work step from man to machine. The automatic good/wrong detection by the camera technology ensures that no deviating and, in case of doubt, faulty assembly sequences are used other than those that have been proven to be the most efficient. The visualization of the assembly steps (Guided Assembly) also means that the worker always has an exact idea of what is expected of him, even without previous experience and training time.
- Effective traceability makes it easier to avoid future errors. The associated efficient, automated documentation also provides proof without additional expense that the assembly was carried out correctly.
- Detailed time responses serve as a basis for measuring the overall plant effectiveness (OEE)
- Explorative visualization offers the possibility of reliably identifying and optimizing both existing best practices and inefficient process deviations.
- Know-how digitization to keep knowledge within the company that would otherwise disappear with the corresponding employees. By means of an assistance system, this wealth of experience is available to all employees throughout the company and in real time.
- The long-term goal is a "Machine data acquisition (MDE) for assembly", thus an assistance system which, thanks to large amounts of data, finally finds the most efficient way of production on its own and converts it into a mimicable process.
Andreas Merchiers ist Professor an der Hochschule Bochum.
Er lehrt und forscht im Bereich Produktionsmanagement und Technische Investitionsplanung. Zusätzlich ist er als Industrieberater tätig.
Seine akademische Ausbildung hat Andreas Merchiers an der RWTH Aachen mit der Promotion zum Dr.-Ing. abgeschlossen. Vorangegangen sind ein Maschinenbaustudium sowie ein wirtschaftswissenschaftliches Zusatzstudium.
Schwerpunktthemen seiner beruflichen Laufbahn bildeten stets die Herausforderungen produzierender Unternehmen: Die Umsetzung des Lean-Gedankens entlang der Wertschöpfungskette, die Gestaltung von Produktions- und Logistikstrukturen sowie die Einführung und Weiterentwicklung von Industrie 4.0 Anwendungen im Maschinenbau.
Benjamin Kemper ist Head of Industrial Engineering bei der DRADURA Holding GmbH & Co. KG.
Er hat sein Masterstudium des Wirtschaftsingenieurwesens 2014 am KIT in Karlsruhe abgeschlossen. Seine Abteilung ist für die Planung und Optimierung der Produktionen von sechs Standorten weltweit verantwortlich. Ein großer Fokus seiner Arbeit liegt auf der Steigerung der Produktivität in der Montage. Dies wird unter anderem durch die Automatisierung sowie den Einsatz von Assistenzsystemen erreicht.