Belt Integrated Vehicular Seat Rear Impact Studies

Static and dynamic studies were conducted with conventional and belt integrated vehicular seats. Most conventional seat backs failed with a static FMVSS 207 rearward torque of approximately 700 to 800 Newton meters (Nm) while integrated seats sustain a comparably measured torque of up to approximately 3,500 to 4,000 Nm. Correspondingly greater rearward changes in speed can be sustained by integrated seats with less likelihood of injury to front and rear seated occupants. The dynamic tests demonstrate the importance of testing within the full vehicle interior structure to insure that floor strength is compatible with seat strength to attain optimum occupant protection in stronger seat designs and to assess injury risk to occupants in collapsing seat designs. The tests indicate that quasi-static seat strength measurements using a more realistic torso body block device can provide reasonable estimates on the ultimate dynamic load capabilities of the seat systems if the seat systems are properly mounted to the vehicle. Quasi-static seat strength results are presented for a variety of conventional collapsing seat designs and stronger seat systems like the belt integrated designs. In addition to the above, some sled buck tests were run with simulated rear seated infants to demonstrate a hazard of front seat collapse into the rear seat area. The results of these tests are also provided and further demonstrate the need for dynamic testing to assess full seat system performance in rear impacts.