Shimmy Control Of Straddle-type Monorail Vehicle With Single Axle Bogies

There are two structural forms of Straddle-type monorail vehicles(SMV),which are SMV with two-axle bogies and SMV with single-axle bogies.Compared with SMV with double-axle bogies,SMV with single-axle bogies have the characteristics of low vehicle resistance,small turning radius,strong passing performance,and lighter weight.However,there is obvious shimmy phenomenon during driving.Shimmy of SMV with single-axle bogies have a significant impact on the comfort,stability,safety and structural fatigue life of the vehicle.It also affect the safe service status and service life of the SMV with singleaxle bogies.How to effectively control the shimmy of SMV with single-axle bogies is significant.This thesis focuses on the shimmy control of SMV with single-axle bogies,based on the theory of multi-rigid dynamics and rigid-flexible coupling dynamics,from bogie structure type and optimization,vehicle system parameter optimazation,and semiactive control based on MR(magnetorheological damper).The study on the shimmy control has been carried out in three aspects.The main work is as follows:1.The kinematics analysis of the space link system of single-axle bogie is carried out,and the multi-rigid body dynamics model of STM with single-axle bogies based on shimmy control is established.and on this basis,sensitivity analysis about influence of the link system parameters on the vehicle shimmy is carried out based on the Pearson correlation coefficient method,a vehicle shimmy optimization control model based on the parameters of the space link system is establised,and the optimization is carried out by the multi-objective particle swarm algorithm.Research on vehicle shimmy control based on optimization of spatial link system configuration parameters is implemented.2.The easily deformed longitudinal traction links such as longitudinal traction links,anti-nodding links,and lateral stabilizer link in the traction mechanism of the single-axle bogie is flexibly processd by the finite element method,and an elastic dynamic model of the spatial linkage is established.On this basis,the rigid-flexible coupling dynamics model of SMV with single-axle bogies is constructed,which lays a foundation for the shimmy simulation analysis,impact analysis and optimal control of the SMV with singleaxle bogies.3.Based on the rigid-flexible coupling dynamics model,the impact analysis and sensitivity analysis of link system stiffness parameters,suspension parameters,tire parameters,and bogie main wheel system geometric parameters on shimmy of SMV with single-axle bogies are carried out,revealing the effect of the link system stiffness and dynamic parameters on the shimmy of STM with single-axle bogies.An optimization model for vehicle shimmy based on link stiffness parameters and an optimization model for vehicle shimmy control based on dynamic parameters are established.Therefore the study on shimmy control for STM with single-axle bogies based on parameter optimization is carried out.It is shown that through the optimization of dynamic parameters,the root mean square yaw acceleration is reduced by 24.16%,the root mean square of the lateral acceleration is reduced by 22.85%,and the lateral stability is improved by 15.25%.4.The semi-active shimmy control scheme of SMV with single-axle bogies is designed integrated the MR phenomenon model,the dynamic model of SMV with singleaxle bogies based on MR is established and effectiveness of the semi-active control of the SMV with single-axle bogies is analyzed by adaptive control strategy.The state parameters after the control of SMV with single-axle bogies is evaluated by the Kalman filter algorithm.The semi-active shimmy control method of the SMV with single-axle bogies based on MR is implemented.It is shown that the root mean square lateral acceleration is reduced by 84.33%,the root mean square yaw acceleration is reduced by78.15%,and the lateral stability is improved by 26.21% by the semi-active shimmy control of SMV with single-axle bogie.It has obvious suppression effect on the lowfrequency vibration of the car body,and the lateral stability of the SMV with single-axle bogies is improved.