What is perceived as complex in final assembly?
Production complexity affects quality, reliability, performance and production time. Due to the high complexity in final assembly, manual assembly is used to handle the high product variety, flexibility and small batch sizes. To improve and find optimal conditions for the worker is therefore essential. The aim of this thesis is to make production companies more competitive by suggesting how production complexity can be managed i.e. reduce risk, handle uncertainty and catch benefits of having such a system. To manage production complexity it first has to be defined and measured i.e. the objectives are to define, measure and manage production complexity. These have been investigated in a case study and field experiments where theory and empirical data was combined to ensure the quality of the research. Production complexity was defined as the interrelations between product variants, work content, layout, tools and support tools, and work instructions. To capture all aspects of the system it was empathized that both subjective and objective aspects should be measured. The subjective production complexity was measured by using the developed method the CompleXity Index (CXI) that simplifies complexity by visualizing the interrelations between the identified elements. To manage production complexity CXI could be used in conjunction with an objective method to prevent complexity and avoid negative effects. Managing production complexity this way could increase quality and productivity, ensure reliability and decrease production time. Future work includes further developing the method and to include organizational and external environmental aspects.