Rear seating systems are still being used in military vehicles as well as in some civilian 4 Wheel Drive (4WD) vehicles. Very limited research work is available in regards to the safety of a rear facing seated occupants in a frontal impact crash. This paper describes a new energy absorbing rearward facing seating system which can be used in a 4WD vehicle to attenuate the deceleration forces in a frontal impact. A series of dynamic sled tests on prototype seats were conducted. A 50% male Hybrid III dummy was used for the sled tests. Both the dummy and the seat were subjected to a 49km/h speed change where the forward crash deceleration was 22 g’s over duration of 100 ms with the seat and dummy positioned backwards. A MADYMO model was then developed and calibrated against the sled test data.
In the calibration process attention was focussed on the head and chest decelerations in the forward direction as well as on the maximum energy absorbed by the prototype seat. Once the model was calibrated it was then used to simulate the same frontal crash conditions where a 95% male and a 5% female Hybrid III dummy respectively were seated in the prototype seat.
The prototype seat, the sled test results, the simulation models and resulting decelerations and injury outcomes are described in the paper. This study showed that by using an energy absorbing seating system, the crash deceleration can be effectively attenuated and occupant injuries significantly reduced in comparison to conventional seating systems.
|1994||Abramoski E, Warmann K, Feustel J, Nilkar S, Nagrant NJ. High chest accelerations in the Hybrid III dummy due to interference in the hip joint. In: Proceedings of the 38th Stapp Car Crash Conference. October 31–November 2, 1994; Fort Lauderdale, FL. Warrendale, PA: Society of Automotive Engineers:281-291. SAE 942224.|