Optimization And Control Of Vehicle's Ride Comfort Based On Robust Design

The vehicle ride comfort will be degraded by factors such as machining errors,wear and tear,and changes in the driving environment,and the suspension has a significant impact on the ride comfort.In order to improve the vehicle ride comfort and the robustness of vehicle ride comfort,this paper considers passive suspension parameter optimization and active suspension control strategy.Taguchi robust design method,vehicle active suspensions fuzzy-PID integrated control method and vehicle active suspensions improved fuzzy-PID integrated control method are applied to a car ride comfort model,and the simulation experiments are carried out to analyze them in depth.Firstly,the vehicle ride comfort model is established.First,the time-domain model of a car's four-wheeled road random excitation is constructed by filtering white noise method;second,the vehicle structure is rationally simplified,and the 8-DOF vibration dynamic model of the vehicle is established by using passive suspension and active suspension respectively;finally,the mathematical model of vehicle ride comfort is obtained by applying the D'Alembert principle and Lagrange equation,and its simulation model is built in MATLAB/Simulink.Secondly,the Taguchi method is used to optimize the passive suspension parameters.The stiffness and damping of chassis suspension and seat suspension are selected as controllable factors,and the interior orthogonal table is designed;the road surface,load and speed are selected as noise factors,and the exterior orthogonal table is designed.Based on the combination of internal and external orthogonal tables,a large number of simulation experiments were carried out to obtain the response values of vehicle ride comfort and handling stability.Through the calculation of signal-to-noise ratio and statistical analysis of experimental data,the influence rules of the controllable factors and noise factors on vehicle ride comfort are obtained,and the optimal combination of the controllable factors is selected.After optimization,the ride comfort and the robustness of the vehicle ride comfort are improved obviously,and the handling stability is also improved slightly.Then,the fuzzy-PID control method is applied to the integrated control of the chassis active suspensions and the seat active suspension.The fuzzy-PID controllers of each active suspension are designed,and the simulation model of the integrated controlof the whole vehicle active suspensions is built in MATLAB/Simulink.The simulation results show that compared with the method of using vehicle passive suspensions,the vehicle ride comfort and handling stability under various road conditions can be significantly improved by the integrated fuzzy-PID control of the vehicle active suspensions.Finally,aiming at the shortcomings of the active suspension fuzzy-PID control,an improved fuzzy-PID control strategy for active suspension considering time-varying road surface is proposed.Through a large number of simulation experiments and analysis,combined with relevant control theory and expert experience,an improved mathematical model of quantization factor,proportional factor and PID parameters and corresponding fuzzy rules are created.The improved fuzzy-PID controller of active suspension is designed,and the simulation model of improved fuzzy-PID integrated control of whole vehicle active suspensions is built.The simulation results show that compared with the vehicle active suspensions fuzzy PID integrated control method,the vehicle active suspension improved fuzzy-PID integrated control method can significantly improve the vehicle ride comfort and the robustness of vehicle ride comfort,and slightly improve the steering stability of the car.In short,the paper applies the Taguchi robust optimization method,the vehicle active suspension fuzzy-PID integrated control method and the vehicle active suspension improved fuzzy-PID integrated control method to gradually improve the vehicle ride comfort and the robustness of vehicle ride comfort.