Towards increasing operator wellbeing and performance in complex assembly

Doctoral thesis, 2018

This thesis provides insights on complex assembly issues and presents pragmatic models, methods, measurable parameters and prototypes that can be used to support operators in complex assembly. Assembly systems are complex partly because of a high degree of product variety and the strategy of having mass-customised products. Complex assembly causes product quality issues, uncertainties and poor ergonomics. Since stress and psycho-social health are emerging problems, it is important to further investigate how complexity affects operator wellbeing and how this and performance can be increased. The aim of this thesis was to investigate and suggest actions that can increase operator wellbeing and operator performance in complex assembly. This was achieved by first identifying and assessing factors influencing operator wellbeing and performance. Five factors were identified as such: work variance, disturbance handling, job satisfaction, motivation and operator emotion. Empirical studies were carried out to investigate what measurable parameters could be used to assess operator wellbeing and performance. The assessment of physiological data in real-time was identified as relevant. Two prototypes were developed to support the factors that were discovered: the DFIP prototype was used to design work instructions to support operator cognition and the DIG IN prototype was used to support operator emotion. The tests and evaluations of the prototypes showed that operator wellbeing and performance can be supported through these prototypes. Two actions were suggested to increase operator wellbeing and performance in complex assembly: 1) supporting cognition through improved assembly instructions and 2) supporting emotion through physiological measurement and environmental data in real time. If these actions are carried out in collaboration with operators (in regard to implementation and usability for example) and do not disrupt the operator workflow, then complexity can be reduced, performance can be increased and a more satisfying and attractive workplace can be created.