Increasing process reconfigurability and quality in HMLV assembly lines using Industry 4.0 : A case study in the automotive industry

Abstract: The automotive industry is responsible for substantial emissions and is therefore transitioning to the new market of electromobility. With changing market conditions and uncertain demand, frequent product launches and customization are increasingly common. Responsiveness has also gained importance, which is why one way to manage the constant change is to use High-Mix-Low-Volume (HMLV) assembly lines. These produce multiple products but at lower volumes, and are characterized by their reconfigurability, i.e., capability to adapt their capacity as well as functionality. The HMLV assembly lines often have high product and process complexity. As a result, standardization and automation of the processes become difficult to realize. Instead, they are dependent on multi-skilled operators and flexible equipment to ensure high quality. Still, the industry continues progressing towards automation and connectivity. Industry 4.0 may facilitate this objective, as well as enhanced reconfigurability and quality in assembly, but despite the increasing interest in the field on Industry 4.0 and related concepts, there is limited research on its potential application for HMLV assembly lines. This report therefore studies the potential of Industry 4.0 to be implemented as a way to combine the strive for increased digitalization with the demand for customization and responsiveness. More specifically, the aim was to provide insights on how Industry 4.0 can improve process reconfigurability and quality in HMLV assembly lines, and to investigate the enablers and barriers to its implementation. To do this, a semi-structured literature review and a multi-case study were conducted. In total, six cases of varying characteristics were investigated through a series of unstructured and semi-structured interviews, site visits and direct observations. Industry 4.0 is built on Cyber-Physical Systems (CPS), which revolves around the integration of physical and digital assets in the manufacturing process. It was found that Industry 4.0 components could improve the reconfigurability and quality at HMLV assembly lines. The literature review presented a framework consisting of six features of reconfigurability: modularity, customization, scalability, convertibility, integrability and diagnosability. Most of these could directly or indirectly be enhanced by Industry 4.0 applications. For example, standardized interfaces in hardware and software were deemed essential for integrability. Mobile modular workstations such as AGVs (Automated Guided Vehicles) were examples of a key asset for scalability and convertibility. Availability, accessibility, and accuracy in data from operations, and effective analytics of the data, could improve modularity and customization. It could also improve diagnosability through predictive maintenance. Connectivity was a prerequisite for systematic data management which could also positively impact the quality. Data enabled a better understanding of processes and was the first step towards improvement. Having real-time data and visualizing it could lead to optimized planning and to addressing issues such as deviations close to the source. Another technology which could improve quality was for example augmented reality for operator training. Several enablers and barriers for Industry 4.0 implementation were identified. The most important enablers were the current paradigm shift towards digitalization, the alignment with agile working ways, collaboration between IT (agile) and production (waterfall/lean), and the synergy between reconfigurable systems and Industry 4.0 implementation. The most prevalent barriers were the lack of IT resources in production, legacy systems and equipment with established ways of working, and the integration of a segregated portfolio of systems. Finally, a recommendation is that all parts of the production system should be reconfigurable: equipment, systems and operators, and the way of working should be compatible with the philosophy.