Research On Forward Design Method Of Minibus Frontal Impact Safety Based On Occupant Restraint Energy

The rapid development of the automobile industry and the increasing of car ownership brought a serious traffic safety problem. In China, the minibus is the primary car to the countryside models. Its holdings accounts for nearly20%of the total, so the frontal crash safety design of minibuses are very meaningful. Low-end user requirements of the minibus caused the low-cost design and manufacturing, but also the minibus must meet our country’s frontal crash occupant protection regulations, therefore the minibus frontal crash safety design is very difficult.In this paper, the method of having the occupant restraint energy central to guide the vehicle safety design is studied, take the minibus crash safety design for example, vehicle frontal crash safety development processes and the relationship between the occupant restraint energy and vehicle packaging design, body design, occupant restraint system design is studied, and provide a reliable guarantee for both of the critical regions design and vehicle safety goals. The main content and innovation of this study are as follows:(1) The development process of the frontal crash safety based on the occupant restraint energy is proposed, the method systematically and effectively guide the minibus front crash safety development to ensure the smooth realization of the vehicle safety goals, to a large extent to achieve the forward design of vehicle safety.(2) The space design method of passenger compartment and front cabin based on the occupant restraint energy is proposed, based on the goals of occupant restraint energy, the max relative displacement of the occupant and vehicle dynamic crush can be determined, and provide the sufficient basis for the safety design of the passenger compartment and front cabin. For the safety design of the passenger compartment at detailed design stage, multidisciplinary collaborative optimization design method is applied to the design of the passenger compartment to realize the multi-performance parallel design of the passenger compartment safety and ride comfort, and to shorten the development cycle. The method is effectively applied to the passenger compartment design of the minibus.(3) The method to reverse vehicle crash pulse based on minimizing the occupant restraint energy is proposed to provide the feasible direction for the conceptual design of crash pulse. Also, for the improvement design of crash pulse at the detailed design phase, the method to design vehicle crash pulse based on minimizing the occupant injuries is proposed to provide the guidance for the vehicle crashworthiness design. The method is effectively applied to the crash pulse design of the minibus, and the engineering practicability is validated by the minibus impact test.(4) The method to design occupant’s chest restraint stiffness based on the chest response waveform efficient is proposed, and provides guidance for the conceptual design of the occupant chest restraint stiffness, and provides a basis to determine the configuration of the occupant restraint system. For the problem of occupant injury indexes sensitive restraint system parameter fluctuations, the robustness optimization design is applied to the parameters design of the restraint system, to achieve the robust Resign of the occupant injury indexes. The validity of the method is validated by successfully applying the fuse seatbelt to the minibus.