Test Results on the Counter Balanced Motion (CBM) SEAT Crashworthiness 2003-01-0498
This paper reports injury load HYGE sled test data and Madymo crash simulation data, all with a Hybrid III 50%ile male dummy. Six frontal crashes and two rear impacts were performed to determine the effect that the CBM Seat has on injury load data in direct comparison to the original equipment seats (OES),
The test series began with a frontal 12g sled crash pulse with CBM Seats less pretensioners compared to OES seats with pretensioners. It shows that the CBM seat reduced the maximum head trajectory by 10°, neck Moment by 48% and femur loads by 60%.
In frontal 20 g sled crash pulses without belt pretensioners, the CBM seats yielded 40% lower forces (-2kN to −1.2kN) compared with pretensioners cases. While with pretensioners, they showed a 42% reduction in HIC values (187 to 107).
In a Madymo 30g crash with CBM, belt and airbag, the HIC was 30% lower than with OES seats, from 478 to 368 with CBM. Rib loads were lowered 33%, from 8.1 to 5.46 kN and tibia loads reduced 70%, from 6.2 to 1.89 kN. However, compression loads at mid lumbar increased 18%, (3.3 to 3.9 kN). This can be addressed by improving the cushioning under the pelvis.
In a 21g rear impact test the CBM reduced head trajectory by reducing head and neck rotation 26°. The peak loads show an 18% decrease in HIC and 6% reduction in neck loads. The CBM seat motion pulsed in concert with the vehicle pulse due to momentum increasing the seat containment angle before peak forces. The seat containment angle rises clockwise as seen in Figures 1 and 2 to counteract the lower body's tendency to escape the seat.
The CBM system accounted for a reduction in injury loads to the legs (36-60%), the neck forces (26%) and HIC values (13-30%) compared to the OES.