MATHEMATICAL ANALYSIS OF RESTRAINT SYSTEM PERFORMANCE WITH THE AID OF A 2-DIMENSIONAL CAR OCCUPANT MODEL

A mathematical model (PSOS, Program for the Simulation and Optimization of Safety Belts) is presented which simulates in two dimensions the motion of a restrained car occupant, by representing in lumped parameter form, the deformations experienced by the human body as a result of belt loading during a crash event. The human body model has ten degrees of freedom. To provide a detailed analysis of restraint system performance, independent simplified models of the body regions contacted by a safety belt and of the restraint system itself were combined with the body model. The model was validated by comparing the computer calculations with the results of a 50 kph barrier crash test with sled and dummy. In view of the pronounced deformation-rate dependence of human chest biomechanics, the presently used belt material with its structural damping behavior (i.e. strain-rate independent loading and unloading characteristics) does not seem to offer optimal protection. It is shown that improved performance within the framework of the mathematical model can be obtained with a restraint system which exhibits a strong viscous (i.e. strain-rate dependent) mechanical component. Such a system would have some capability of adapting its stiffness over a wide range of crash conditions and occupant characteristics.

• Supplemental Notes:
  • Published in HS-030 722, "International IRCOBI Conference on the Biomechanics of Impacts (5th) Proceedings," Amsterdam, 1980, pp 25-34. Conference held in Birmingham, England, 9-11 September 1980.
• Corporate Authors:

  Institute of Biomedical Engineering

  Zurich,   Switzerland 
• Authors:
  • NIEDERER, P
• Publication Date: 1980

Media Info

• Features: References;
• Pagination: 10 p.

Subject/Index Terms

• TRT Terms: Biophysics; Crash injury research; Design; Manual safety belts; Mathematical models; Optimization; Performance; Simulation
• Old TRIS Terms: Optimum design
• Subject Areas: Design; Research; Safety and Human Factors;

Filing Info

• Accession Number: 00372661
• Record Type: Publication
• Source Agency: National Highway Traffic Safety Administration
• Report/Paper Numbers: HS-030 725
• Files: HSL, USDOT
• Created Date: May 31 1983 12:00AM