Research On Driving Stability Of Three-axle Heavy Vehicles

Emergency rescue vehicles have certain requirements for their mobility and safety because of their working environment and their own structure.Through investigations,domestic and foreign scholars have done less research on the steering and driving of multi-axle heavy vehicles,so the research on the driving stability of emergency rescue vehicles has theoretical significance and practical application value.This article combines the key research and development project "High mobility emergency rescue vehicle(including fire truck)special chassis and suspension key technology research and development(No.: 2016YFC0802902)" to improve the handling stability of the vehicle as the research goal,and the control model of the three-axle heavy vehicle The active suspension controller,the steering state controller and the simulation and test of the whole vehicle system are analyzed and researched.This article first established the ideal reference model of the three-axle vehicle with two degrees of freedom,and then built the nine-degree-of-freedom model and15-degree-of-freedom model.Then,based on the LQR theory,the vehicle’s active suspension controller was designed,and then the improved genetic algorithm was used to optimize the parameters of the suspension controller.After that,the fuzzy feedback controllers based on the yaw rate,the side slip angle of the center of mass and the joint control of the two were designed respectively,and then based on the joint fuzzy feedback controller,the fuzzy controller with dynamic fuzzy factor was designed.Finally,the simulation and test of the active/passive suspension vehicle are carried out.The analysis of the test results shows that compared with the passive suspension,the corresponding index of the vehicle with active suspension in the pure(combined)working condition drops by 49.08%(4.47%)、 22.78%(5.66%)and 87.19%(71.76%),verifying the correctness of the vehicle handling model and the effectiveness of the controller.