Comparing two methods to measure assembly complexity from an operator perspective

As the number of product variants, components, and changes increase manufacturing companies experience a strong need to reduce or handle complexity. Therefore, two research projects, in Sweden and Belgium, have developed methods for measuring the level of complexity in production stations. This paper presents and compares the methods. The Belgian CompleXity Calculator, CXC, measures complexity using objective parameters, collected from data systems. The Swedish CompleXity Index, CXI, focuses on a subjective measure of complexity, as experienced by operators in the stations, collecting data using a questionnaire. Both methods overlap in content, and are validated by industrial cases with positive results. CXI is validated towards correlation with objective data, and CXC is validated by correlation with subjective data. Both methods have added value compares to the intuitive view of complexity, by providing more detail, structure, indication of solutions, and by getting involvement to complexity issues. The two methods have merits and by using both methods in conjunction, synergy can be achieved. This synergy would give a possibility to first automatically and objectively do an overall scan of all the plant's stations, and then subjective in-depth studies could be performed.