A novel method of analyzing quality defects due to human errors in engine assembly line

Human error is one of the most important reasons for quality defects in the manufacturing systems. In this paper, the assembly line of automobile engine was taken as an example, the human error induced quality defects and the corresponding root causes and their relative importance were explored thoroughly. Thereby, a novel approach of analyzing human error induced quality defects was proposed based on integration of improved CREAM (Cognitive reliability and error analysis method) and FTA (Fault tree analysis). The new method was established based on a case study of an automobile engine assembly line. The research results showed that this method could provide theoretical basis and practical guidance for evaluation and controlling of the human error induced quality defects.