| With the rapid development of economy and trade around the world,road transport plays an increasingly important role in the development of countries and regions.As the main vehicle for road transportation,automobiles play a major role in the flow of people and goods.The use of automobiles is extremely wide and the working conditions are complex.This puts forward higher and more comprehensive requirements for the performance of the car.The ride comfort and handling stability of a car have a great influence on the smoothness,integrity,driving stability,and safety of people and goods.The ride comfort and handling stability of a car are a pair of interrelated and mutually constraining properties,so it is necessary to further analyze these two properties.At present,most of the studies on ride comfort and handling stability are independent studies.A hypothesis of ride comfort research assumes that wheel angles are not considered,the vehicle’s handling behavior is not considered.A hypothesis of handing stability studies is that the vehicle is traveling on a flat road surface.The traditional research results of ride comfort and handling stability only simulate these two properties together,and there is no in-depth analysis of the synergy between these two properties.Based on the flatness model and space model of ride comfort and handing stability,this paper establishes the open-loop cooperative model of ride comfort and handing stability.Ride comfort and handling stability open-loop and closed-loop cooperative simulation analysis.In order to gain a deep understanding of the relationship between ride comfort and handling stability,this also provides the basis for the ride comfort and handing stability optimization and control,and helps to improve the overall performance of the car.The main research contents of this article include:(1)Build a flat and a space model for ride comfort based on plane hypothesis and spatial hypothesis.Based on Newton’s second law,a flat and a space model for handling stability under tire lateral force input are established.Among them,the lateral stiffness bar’s roll stiffness was considered when the space handing stability model was established.The space handing stability model is based on the suspension force and can be applied to various road surfaces,later will be degenerated to a flat road surface.Determined the main response of ride and handling stability.(2)Based on the filtered white noise method,establish the front and rear wheel road surface model and the four-wheel rode surface model.Based on the coupling analysis of state variables,the planarity and space models of ride comfort are integrated with the plane and space models of handing stability,then the plane cooperative model and the space cooperative model are established.A handing wheel angle step,angular pulse,and sine input signal for open-loop simulation was established.The simulation results were compared with the ordinary ride comfort and handling stability models.The analysis results show that the planar cooperative model can reflect the influence of road surface excitation on the response of the handing stability.The response of the handing stability of the cooperative model will fluctuate near the steady-state value due to the influence of the road surface excitation.However,the response of different handing behaviors to the flat model cannot be reflected.The spatial cooperative model can reflect the synergetic influence relationship between ride comfort and stability.However,for the acceleration of the center of mass of the body and the pitch acceleration of the body,the handing behavior has little effect on these two responses.(3)Based on the prediction-following theory,a single-point previewing optimal curvature driver model is established,the transfer function form,frequency domain representation and time domain representation of the driver model are obtained.The matrix form of the optimal curvature driver model is determined.A two-degree-of-freedom,three-degree-of-freedom handing stability model was established to model the driver’s model in a single point of view.The driver model is introduced into the planar cooperative model and the spatial cooperative model,and a closed-loop planar cooperative model and a closed-loop spatial cooperative model are established.Using polynomial or trigonometric fitting functions to perform single shift,double shift,and serpentine traffic condition fitting,a road path input model under closed-loop conditions was established.Prepare the corresponding matlab program.Simulations of plane and space cooperative models under single shift,double shift,and serpentine conditions were performed.The cooperative simulation results were compared with the ordinary ride and handling stability models.The analysis results show that the closed-loop cooperative model can realize the path tracking of the closed-loop operation and stability under various conditions,and can also perform the cooperative simulation and contrast analysis of the ride comfort and the ride comfort under the closed-loop conditions.This has a certain role in promoting a deep understanding of the relationship between ride comfort and handling stability.This cooperative model also provides a certain basis for the cooperative optimization and control of ride comfort and control stability,which is conducive to the improvement of the overall performance of automobile development.In the increasingly fierce competition in the automotive market,major automakers urgently need to improve the overall performance of their vehicles.The two coupled and contradictory performances of ride comfort and handling stability are of great practical significance if they can be effectively studied and analyzed.The cooperative model was established based on the ride comfort and handing stability.The synergy effect between ride comfort and handling stability is analyzed,which has certain significance in promoting the relationship between these two properties. |
