Stability Control Of Straddle-type Monorail Vehicle Based On Magnetorheological Fluid Active Vibration Reduction

Straddle-type monorail,as a special rail transit system,can effectively improve transportation safety performance,alleviate traffic congestion,improve road traffic efficiency,and reduce energy consumption.During the operation of monorail vehicles,factors such as the small turning radius,the special structure of monorail vehicles and the unevenness of track beams cause the running stability of monorail vehicles to decrease.Therefore,the stability control research of monorail vehicles is carried out to improve the safety of monorail vehicles.And ride comfort is of great significance.This thesis takes straddle-type monorail vehicles as the research object.Aiming at the problem that the damping of traditional hydraulic shock absorbers cannot be adjusted adaptively,based on the new smart material magnetorheological fluid,a magnetorheological fluid for straddle-type monorail vehicles is designed.Active shock absorbers,and perform performance optimization and active control,thereby effectively improving the running stability and riding comfort of monorail vehicles.The main research contents are as follows:(1)Research on the influence of monorail vehicle suspension parameters on running stability.Analyze the monorail vehicle bogie structure,obtain the monorail vehicle system topology structure diagram,consider the influence of track beam unevenness,use multi-body dynamics analysis software to establish the straddle monorail vehicle bodybogie-track beam system dynamics model based on this,the influence of suspension system parameters on the running stability of monorail vehicles is analyzed,and the necessity and feasibility of active control of the shock absorbers of monorail vehicles are verified.(2)Multi-objective optimization design of magnetorheological fluid active shock absorber for monorail vehicles.According to the working characteristics of the singletrack vehicle shock absorber,a design scheme of a magnetorheological fluid active shock absorber with built-in parallel double coils is adopted,and its structural parameters are designed and calculated.A joint simulation optimization platform for the magnetic circuit structure was built,the sensitivity of the magnetic circuit structure parameters was analyzed,and the magnetic circuit of the shock absorber was optimized based on the NSGA-Ⅱ algorithm.The optimization results were simulated and analyzed.The results showed that the optimized the output damping force of the shock absorber meets the design requirements.(3)Research on control characteristics of magnetorheological fluid active damper based on variable universe fuzzy control.Based on the mechanical model of the magnetorheological fluid active shock absorber,the damping characteristics of the shock absorber are simulated and analyzed.The BP neural network is used to establish the inverse model of the shock absorber,and the nonlinear mapping relationship between the running state of the shock absorber and the required current intensity is obtained.A twodegree-of-freedom suspension model based on a magnetorheological fluid active damper is established,a variable universe fuzzy controller is designed,and simulation verification is carried out.The results show that the variable universe fuzzy control strategy can effectively suppress vehicle body vibration.(4)Research on the stability of the monorail vehicle based on magnetorheological active vibration reduction.Combining the complete vehicle dynamics model of the monorail vehicle and the control characteristics of the magnetorheological fluid active damper,a UM-Matlab/Simulink co-simulation platform was built to simulate and analyze the running stability of the monorail vehicle under different operating conditions.The simulation results show that,straddle-type monorail vehicles using magnetorheological fluid active vibration reduction have better stability under different operating conditions.