Mirja Meyer

• Today's manufacturing companies are faced with a large number of fluctuating influence factors, as supply chains in the production environment grow larger with more suppliers and highly sophisticated products. At the same time, throughput times and due date reliability need to stay on a stable level, to fulfill the expectations of short delivery times and high service-levels of increasingly demanding customers. This ability to maintain specific features or a certain performance when subject to fluctuations and disturbances is generally referred to as robustness. As explained above, robustness of performance indicators, such as due date reliability, is a desirable characteristic for producing companies, hence the question arises how it can be achieved or incorporated in a companies manufacturing system. Looking at other scientific disciplines, such as biology or complex network science, robustness of the respective systems is often caused by redundancy, a situation where identical or similar components can replace each other when a component fails. In manufacturing research, redundancy has often been considered as an aspect to be avoided, as it stands in a potential trade-off with cost-efficiency, for example in lean manufacturing where excess inventory is considered as waste. However, as redundancy has been shown to have a strong relation to robustness in other disciplines, the aim of this thesis is to investigate the role that redundancy plays for achieving robustness of manufacturing system performance.