Identifying the task variables that influence assembly complexity

Little is known about the variables that affect performance in assembly tasks. Seven assembly task variables were identified based on previous literature and a task analysis of self-assembly products. As real world assemblies could not be controlled sufficiently, the values of the assembly task variables were systematically varied in 16 abstract assemblies. Sixteen sets of assembly instructions were presented to 38 participants who were instructed to compare them to a final model and indicate whether following the instructions would result in the production of the final model (the time taken to accomplish this is a reflection of assembly complexity). The five task variables studied were found to be significant predictors of assembly task complexity. The results show the need for continued investigation and are a step towards the development of methodologies for the prediction of assembly difficulty.