Dynamic analysis and design optimisation of the seat belt pretensioner

In this paper, the dynamic model of the high-power pretensioner used for the seat belt of a passenger vehicle is developed. The operating device of the pretensioner is optimised to improve the length of the web retraction. The three-dimensional rigid dynamic model of the pretensioner is created using the commercial multi-body programme, ADAMS, and the nonlinear spring element is used to represent the seat belt. The reliability of the dynamic model is validated by comparing the simulation results with the actual test results. The pretensioner presented in this paper is operated by the rack and pinion gear mechanism. The profile of the rack and pinion is optimised to improve the retracting performance of the pretensioner using the design of experiments. The optimised rack and pinion gear is applied to the dynamic model, and the optimisation results are verified by comparing the simulation results of the original and the optimised model.