Investigation of Restraint Characteristics for Elderly Occupant Chest Injury Reduction

Objective: In recent years, the increase in the number of traffic accident fatalities of elderly in Japan is one of the urgent tasks for future traffic accident countermeasures. Moreover, from the trend of a global aging society, in the future it is expected that the number of traffic fatalities involving the elderly and the importance of correspondence will also increase. In this research, in order to cope with the reduction of elderly traffic accident fatalities, chest injuries are focused on as one of the factors of elderly occupant fatalities, measures to reduce chest impact of elderly occupants at the time of a frontal collision are examined and then, the direction of the corresponding technology required for realization was considered. Methods: In this study, using a human body FE model with different physiques to reproduce the bone characteristics and skeletal shape of both adults and elderly people, frontal collision simulations within different collision speed ranges were performed. Comparison of chest injuries was undertaken of elderly occupants, which can occur in the middle and low speed range, to adults. Examination of optimum occupant restraint characteristics by seat belts enabled chest injuries of elderly occupants to be reduced to the same level of adults. Then, the effect of reducing elderly occupant’s chest injuries in each physique was confirmed. Results: The occupant restraint characteristic by the seat belt calculated was able to confirm the chest injury reduction effect of an elderly occupant in each physique in the front collision in the medium to low speed range. In addition, this restraint characteristic combines the restraint characteristics for reduction of chest injuries of elderly occupants with different physiques, and secondary collision damage reduction. Discussion and Limitations: In this research, focus was on medium and low speed and frontal collision. In order to realize this occupant restraint characteristic, it was necessary to be compatible with occupant protection performance in the collision mode of each regulation. For this purpose, achieving sensing technology to determine the severity of car body deformation at the time of a collision, occupant protection system technology that can change occupant restraint characteristics according to the situation is essential. In order to further reduce the number of deaths, it is necessary to investigate occupant restraint characteristics that can reduce injuries, and look at other measures for reducing chest injuries in the high speed region for each type of collision. Conclusion: In this study, the authors used a human body FE model with different physiques to calculate the occupant restraint characteristics necessary for a reduction of chest injuries of elderly occupants and reduction of secondary collision damage in frontal collisions in the medium and low speed range, and confirm the effect. In order to further reduce elderly occupant injuries, as a type of integrated safety technology with more damage mitigation effects, collision prediction technology by evolution of ADAS’s external detection technology uses identification of an occupant’s physique, posture, and age judgment technology It is necessary to evolve protection device technology, which can vary occupant restraining force and time according to situation and occupant.


  • English

Media Info

  • Media Type: Digital/other
  • Features: Appendices; Figures; References; Tables;
  • Pagination: 14p
  • Monograph Title: 26th International Technical Conference on the Enhanced Safety of Vehicles (ESV): Enabling a Safer Tomorrow

Subject/Index Terms

Filing Info

  • Accession Number: 01763050
  • Record Type: Publication
  • Report/Paper Numbers: 19-0275
  • Files: TRIS, ATRI, USDOT
  • Created Date: Dec 22 2020 4:23PM