Research On Pretensioner Seat Belt Protection Efficiency

Nowaday, vehicle have became a closely related tools for human being, not only as a outcome of the development of human technology, but as a symbol of free dream for the people who pursue of speed and easy life. In recent years, with the popularity of vehicle knowledge, people paid more and more attention to the harms, esprcially the harms that caused by traffic accident, that brought by vehicle.This conceptual changes, at one hand, promoted the introduction of vehicle safety rules, which gave stringent demand on the vehicle safety performance, at the other hand, increased the sales number of vehicle which is good at safety performance, so that made the manufacturers are more willing to increase the input for vehicle safety research. This all result the vehicle safety technology to a great developing.Vehicle collision safety technology is an important part of vehicle safety technology. Seat belt is the most efficient and most popular protective device in vehicle collision safety system, human has never stoped its research and improving. Pretensioner seat belt as the most advanced form of seat belt, has better safety performance and can compatible with other protective devices, that improve the efficiency of whole system.This paper use simulation tools, to optimize the key parameters of pretensioner seat belt, and reached the purpose to enhance the overall protection efficiency of pretensioner seat belt.Through the physical teardown and used CATIA software to set up3D model, to explain the structure and theory of pretensioner seatbelt in detail, and used kinematics simulation to verify the rationality of its structure and validity of the model.Builded up the simulation model in MADYMO software, including multi-body model of driver, mixed model of seat belt, finite element model of airbag, and accurately set the parameters of seat-belt pretensioner and load limiter. On this basis, set input values, calculate the simulation results, and compare with real vehicle collision test results. Modify the original model on the basis of the analysis results, until the results matched with test data.Using sensitivity analysis method to analyze the sensitivity of pretensioner seatbelt system’s parameters, according to passenger’s damage index. Choose four parameters of great influence, orthogonal experimental design for these four parameters, analysis of range according to the results, get the optimal level of each parameter, then get the optimal combination of parameters.Compared the output of the optimal combination model and original model, head injury indicators HIC decrease of36.57%, completely injury indicators WIC also reduced by nearly20%, very effective in improving the efficiency of passenger safety protection.