The importance of a vehicle sub-frame is often discussed in vehicle compatibility. To observe how the sub-frame geometry influences the vehicle response, three different sub-frame configurations were modeled and simulatedin US NCAP crash test configurations as well as car-car simulations. The former simulations were used to observe how the design changes would influence self protection in a crash test influencing the original design of the vehicle. The latter simulations were to observe how the modification would influence vehicle compatibility under "real world" conditions. The rigid barrier impacts could detect the changes in the design. The most forwardplacement of the sub-frame had a stiffer response than the other configurations as observed in acceleration pulse and barrier wall loads. Self protection also tended to be improved over the baseline configuration. In car-car testing, it was difficult to identify a clear subframe configuration that provided improved compatibility. Both the standard and forward placed subframe had better performance than the most rearward configuration. Neither the baseline nor extended sub-frame versions were clearly better for all car-car impact configurations but an extended sub-frame exhibited better self protection, especially when the vehicle was lower than its collision partner. The full text of this paper may be found at: http://www-nrd.nhtsa.dot.gov/pdf/esv/esv21/09-0403.pdf For the covering abstract see ITRD E145407.
Abstract