Driver's Fatigue Evaluation During Long Term Driving for Automotive Seat Development

An important issue in automotive seat comfort is reducing driver fatigue during long-term driving. In this paper, a finite element model of the seat and the human body was developed, and stress analyses around the lumbar vertebrae of the human body were carried out. A long-term driving test on a compact car seat was conducted by using a driving simulator, and increases in the stress hormone adrenaline in the urine of the subjects were measured. Correlations between physical seat data and increases in adrenaline were analyzed, and the seat parts causing body fatigue were identified. The results of the long-term driving test were compared with the results of the finite element analysis, and an attempt was made to clarify the mechanism responsible for the fatigue.