Robust Optimization Design On Axlebox Suspension Parameters Of High-speed Passenger Train

Abstract:With the increasing speed of the railway passenger train, safety and comfort have become the focus of research for dynamic performance of high-speed railway passenger train. In this dissertation, the robust optimization design on axlebox suspension parameters is carried out by taguchi method and six sigma method. Under the influence of uncertain factors, axlebox suspension parameters are optimized to reduce the sensitivity of dynamic performance. It has direct guidance to improve safety and comfort of vehicle.The structure, characteristics and composition of axlebox suspension system are dissected. Components and degree of freedom of high-speed passenger train are analysed, topological structure of vehicle multi-body system is established. Then multi-body dynamics simulation model of the high-speed vehicle is set up by SIMPACK. Axlebox suspension parameters are selected as design parameters, the influence rule, which the axlebox suspension parameters to stationarity and stability, is obtained by dynamics performance simulation.With taguchi method and multidisciplinary optimization software Isight, the process of taguchi robust optimization to axlebox suspension parameters is built by Isight integrating SIMPACK. Passenger capacity, speed and curve radius are selected as noise factors, the axle suspension parameters are selected as controllable factors, axlebox suspension parameters are optimized by taguchi robust optimization. The robust optimal solution of axlebox suspension parameters are obtained through the signal-to-noise ratio (S/N) analysis, stationarity and stability of the vehicle is improved. Under the influence of external factors, the vehicle dynamic performance is more stable and reliableWithout considering outside noise factors, stationarity and stability index are selected as the objective function, multi-objective optimization model is established. Then, considering passenger capacity, speed and curve radius, multi-objective robust optimization model is built by six sigma method. Under Isight-SIMPACK integration environment, deterministic optimization and six sigma robust optimization to axlebox suspension parameters are realized. Compared with the running stationarity and stability of deterministic optimization and six sigma robus optimization, the results show that six sigma robust optimization not only improve the vehicle dynamic performance,and make the robustness of vehicle dynamic performance obviously improved.With monte carlo simulation technique, axlebox suspension parameters which have been obtained by taguchi method and six sigma method to effect of stationarity and stability are compared. The results found that the mean and variance of stationarity and stability are smaller by six sigma method than taguchi method. The results show that the vehicle dynamic performance is more stable and reliable, and anti-interference ability is stronger by six sigma robust optimization design to axlebox suspension parameters of high speed passenger train.