Comparing And Studying The Two Driver Directional Control Models

The driver, the vehicle and the road compose an organic system. To solve the problem of the vehicle's handling and stability completely, the driver, the vehicle and the road must be considered to be of the same system. Obviously, the driver's behavior model is the center of the driver-vehicle closed-loop system. So, it is very important to build the driver model which is correct and according with the actual human driver and it is also important to describe and evaluate the driver-vehicle closed-loop system.This paper focuses on the function of the driver-vehicle closed-loop system and the application of the directional control driver model. Starting with the theory which the two models based on and their typical part, the main work is as follows:Firstly, aiming at the need of the driver model and its researching actuality, the method of POANN Driver Model was introduced on the basis of the Artificial Neural Network, and a simplified POANN Driver Model was presented with respect to the coordinate transfer, driver's preview input and driver's delay. Furthermore, the Error Elimination Algorithm (EEA) in driver modeling was introduced based on the Preview-Follow theory. The complicated vehicle model in CarSim was simplified to be a two-freedom linear model based on the system identification theory. Also discussed in the paper is the application of POSANN Driver Model with regard to the complicated vehicle model in CarSim based on the EEA analysis method by means of variable subroutine and how the typical steering wheel angle and its value input influence the final precision.Secondly, starting with the modern control theory, the basic point of the OPC(Optimal Preview Control)model and the process of building the OPC model is introduced, the optimal steering wheel angle which can make the error distance between the ideal path and the vehicle's lateral position least during the preview time is got basing on the extremum principle of the optimal control theory, a simplified OPC model was presented with respect to the coordinate transfer, driver's preview input and driver's delay. The application of the OPC model in CarSim software is also discussed.Thirdly, basing on the front work, starting with the theory of building the two driver models, the typical part and the basic theory are analyzed, and the aspect about how the parameters in the typical part influence the simulation result is compared.Fourthly, the two driver models are built under CarSim software. Because the OPC model has been the internal model in CarSim, for validating if the model built is correct, the same parameters which is got from the model just built is put to CarSim and the same simulation is done, the simulation result indicates that the model built was correct.Fifthly, the parameters of the two driver model are identified on the purpose of the error distance between the ideal path and the vehicle's lateral position is least during the preview time under three types of speeds and also in the condition of double lane change and slalom, and the method which the literature [9] recommended is used to evaluate the capability of the two driver model.Sixthly, aiming at the application of the driver directional control model, the evaluation methods and the relationship between them are recommended, the objective evaluation system for vehicle's handling and stability is paid more attention, at last, the vehicle model in CarSim is chosen and the parameters which have more influence on the vehicle handling and stability are modified, and the evaluation system is used to evaluate the four types of vehicle.