Dynamics And Control Mechanism Of The Effect Of Road Alignment On Vehicle Path Deviation

In recent years, the rapid development of China highway occurs, but traffic safetyissues are becoming increasingly serious. And the various elements of road traffic safetysystem as a complex closed-loop system are interrelated and interacted. The impact of roadconditions which is the car and the driver’s body on traffic safety can’t be ignored. Andvehicle path as the output of the system is an important indexes which evaluate designcomfort and safety of the road alignment. Therefore, we need to study the mechanism ofroad alignment on vehicle track, which in turn can provide guidance for alignment design,consequently optimize the linear parameters, reduce the traffic accident rate and increase thetransportation safety.Considering the complexity of the interrelationship of various factors in thedriver-vehicle-road system, this paper studies the properties of the traffic path from thedynamics and control angle by the means of computer simulation. We established dynamicsimulation platform and improve the parameters in the model. On the basis of experimentalwe integrate the results simulation analysis results and analyze the influence of the differentroad conditions on vehicle trajectory. Specific content as follows:1. Set up the closed-loop control simulation model in which the driver is controlsubject, the car is the control object and road alignment is control input. Among them, thecar model is based on model of three degree of freedom in which state variable are verticalspeed, lateral speed and yaw velocity. On this basis, realize the coupling of the three modelsby leading the driver preview optimal curvature model and road plane linear model.Develop the corresponding simulation program by taking advantage of Matlab and set upthe road alignment simulation evaluation platform.2. Taking Antu-Erdaobaihe K27section for an example, this paper studies theinfluence of preview time in the driver model on simulation results based on the simulation platform. Therefore, on the basis of study in the domestic and foreign, fit the changerelation of preview distance with road curvature and vehicle running speed, improve thepilot model, make the system more suitable for road safety simulation and establishparameter model which is more applicable to road safety.3. Develop vehicle trajectory measuring system. We carry out a secondary road test inthe mountainous area, obtain the parameters of the vehicle running speed, driving track andthe road alignment and set up corresponding test database. Using the method of statisticalanalysis, vehicle path statistical characteristics in mountain road are researched. Andcomparing the statistics data of different sections, we find the impact characteristics of roadalignment on vehicle path.4. In the dynamic simulation platform, vehicle state is reproduced in the mountainexperiment road. Comparing simulation and measured results, verify the correctness of themodel and parameters. By changing the system parameters, carry through the simulationresearch and obtain the change rule of path deviation under the circumstances of differentdrivers at the distance, road adhesion coefficient. Explain the mechanism of influence ofroad alignment on vehicle trajectory.From the above, this paper puts forward from the angle of car dynamic characteristicsto the influence of road alignment on vehicle trajectory and makes comprehensive analysisby using the computer simulation model, from a certain degree to reveal the formationcause of traffic accident.